PS-7-M series
Extractive Pump Gas Detector(detachable sensor/sampling units)
Instruction Manual Keep this manual for easy reference.
 Carefully read this manual prior to use.
 This manual describes the standard model. If your unit has end-user-specific options, thismanual will be superseded by your delivery specifications.

Instruction Manual No.
GAE-138-02
September 2022

 Unit Dimensions andComponents

 Sensor Unit
Installation/Replacement

5. “Unit Dimensions and Components”

9-2. “Sensor Unit Installation

on page 6.

/Replacement” on page 41.

 Base Unit installation/Wiring
6. “Installation and Wiring” on page 12.

 Operation
7-1. “Operation” on page 19.
For checking normal operation, referto page 30.

Cable
entry

OUT
IN

 Gas Alarm Trouble Alarm

7-2. “Operation - Gas Alarm”

7-3. “Operation - Trouble Alarm”

on page 30.

on pages 32.

Flashing red LED

Flashing
amber LED

 Troubleshooting

10. “Troubleshooting” on page 46.

Table of Contents
1. Introduction .......................................................................................................... - 1 1-1. Manuals and related documents .................................................................... - 1 1-2. Overview ........................................................................................................ - 2 2. General Precautions ............................................................................................. - 3 3. Package Contents................................................................................................. - 4 4. Block Diagram ...................................................................................................... - 5 5. Unit Dimensions and Components ........................................................................ - 6 5-1. Exterior Appearance ....................................................................................... - 6 5-2. Main Unit ........................................................................................................ - 7 5-3. Base Unit ....................................................................................................... - 8 5-4. DIP Switches .................................................................................................. - 9 5-5. Operation Buttons ........................................................................................ - 10 5-6. LCD Indicator Icons ...................................................................................... - 11 6. Installation and Wiring ......................................................................................... - 12 6-1. Wiring Procedure ......................................................................................... - 13 6-1-1 Modbus TCP (Ethernet) Wiring Procedure ................................................. - 15 6-1-2 Modbus RTU (RS-485) Wiring Procedure .................................................. - 15 6-2. Unit Installation Procedure ........................................................................... - 17 6-3. Tube Fitting Connection Procedure .............................................................. - 18 7. Operation ............................................................................................................ - 19 7-1.Operation Procedure ..................................................................................... - 19 7-2. Operation - Gas Alarm.................................................................................. - 30 7-3. Operation - Trouble Alarm ............................................................................ - 32 7-4. Operation - Test Mode .................................................................................. - 34 7-5. Operation - Maintenance Mode .................................................................... - 35 8. Maintenance ....................................................................................................... - 37 9. Consumable Parts Replacement......................................................................... - 40 9-1. Filter Element Replacement ......................................................................... - 40 9-2. Sensor Unit Installation/Replacement ........................................................... - 41 9-3. Sampling Unit Replacement ......................................................................... - 44 10. Troubleshooting ................................................................................................ - 46 11. Specifications .................................................................................................... - 48 12. Warranty ........................................................................................................... - 50 13. Service Life of Detector ..................................................................................... - 50 14. Disposal of Detector/Sensor/Sampling .............................................................. - 50 15. Detection Principle ............................................................................................ - 51 15-1. Electrochemical (Catalyst conversion) Sensor (CDS-7).............................. - 51 15-2. Hot-wire Semiconductor Sensor (CHS-7-CH) ............................................. - 51 15-3. Catalytic Sensor (CHS-7-CS) ..................................................................... - 51 15-4. Galvanic Cell Sensor for Oxygen detection (COS-7) .................................. - 51 16. Glossary ........................................................................................................... - 52 -

1. Introduction
1-1. Manuals and related documents
The following documents are prepared for use of this product.
1. PS-7-M series gas detector’s instruction manual (This document, Doc.No.GAE-138-xx)
This document provides the following information to ensure safe use of this product.
 Safety precautions
 Installation and wiring
 Basic configuration, block diagram, unit dimensions and components
 Operation and mode setting
 Maintenance, parts replacement, and action to take in the event of a failure
A manual is provided per system and not per unit.
2. PS-7 gas detector’s operation manual for administrators (Doc.No.GAE-019-xx)
This document is intended for your system administrator.
 Password
 Changing Settings
All the items set for this product (e.g. alarm set values) are password-protected.
A manual is provided per system and not per unit.
3. PS-7 pyrolyzer’s operation manual (Doc.No.GAE-020-xx)
This document describes installation and replacement procedure for a pyrolyzer (sold separately).
A manual is provided per system if the system includes a sensor unit with pyrolyzer.
4. PS-7-M communication specifications guideThis document provides communication specifications and the configuration procedure toestablish communication with external devices. This document is not included in a standard
package. If needed, please contact New Cosmos or its authorized representative to obtain it.
5. PS-7-M IP address setting guideThis document describes how to set/change an IP address by using a web browser to establish
communication with external devices. This document is not included in a standard package. If
needed, please contact New Cosmos or its authorized representative to obtain it.

-1-1-2. Overview
 Thank you for purchasing the New Cosmos PS-7-M series extractive pump gas detector. Prior
to use, please read this instruction manual to ensure safe and reliable operation.
 This unit supports RS-485 and Ethernet communications. For information on Modbus interface
communication specs, please read the PS-7-M communication specifications guide.
 This unit detects semiconductor process gas or combustible gas (e.g. hydrogen) that may bepresent in a cylinder cabinet, exhaust duct, or industrial facility work environment (e.g.
semiconductor manufacturing plant), and relays the gas concentration value as an analog signal
and a RS-485 or Ethernet signal to an external device while simultaneously displaying the gas
concentration value on its display.
 If gas concentrations reach a preset level, the red ALARM LED will start flashing and activate
relay contacts, thus monitoring the concentration of a leaked target gas.
 Sensor and sampling units can be easily replaced without tools. After a sensor/sampling unit
replacement, on-site calibration using a prepared gas is not necessary.
 Periodic maintenance is essential to maintain the reliability of your detector. Perform periodic
maintenance in accordance with the instructions given in this manual.
 PS-7-M series gas detectors are divided into three models according to the sensor unit type andwith/without a pyrolyzer. For sensor selection, please contact New Cosmos or its authorized
representative.
Sensor unit (sold separately)
Toxic gas sensor unit (CDS-7)
Combustible gas sensor unit (CHS-7)

Model
PS-7-M-01

Oxygen (COS-7)

PS-7-M-02

Toxic gas sensor unit (CDS-7) with pyrolyzer (CDP-7)

PS-7-M-03

 This product is CE-marked, but its RS-485 communication function is outside the scope of the CE
marking.
 Modbus® is a registered trademark owned by Modicon Inc. (Schneider Automation international).

Symbols Used in this Instruction ManualThis manual uses Danger, Warning, Caution and Note symbols to draw attention to procedures,materials, methods, and processes, which require particular attention.

DANGER

Indicates an imminently hazardous situation that can result in deathor serious injury.

WARNING

Indicates a potentially hazardous situation that may result in deathor serious injury.

CAUTION

Indicates a hazardous situation that may result in minor injury orproperty damage.

NOTE

Provides information on product handling.

-2-2. General Precautions
 Carefully read this manual prior to use.
 To ensure safe operation, follow the precautions below.
 Wiring and installation should only be performed by a qualified electrician with knowledge of
wiring/installation procedures.

DANGERThis product is not explosion-proof equipment and should not be installed in ahazardous area.

WARNINGIn the event of a gas leak alarm, follow safety procedures in accordance with yourcompany's regulations.



Ground the detector to prevent electric shocks.

CAUTION

Do not disassemble, modify, or alter the structure of this unit or its electrical circuits.
Doing so may compromise the performance of the product.

This product is not drip-proof equipment and should be kept away from splashing water.



Only use this product in accordance with applicable laws and regulations.

-3-3. Package Contents
The following items are included in a standard package. If any items are missing or
damaged, please contact New Cosmos or its authorized representative for replacement.
Table 1. Standard contents
Item Name

Qty.

Gas detector (PS-7-M)

1

Half union (male connector)
R1/4- ø6mm or R1/4- ø1/4 in. (selectable)

2*1

Replacement filter elements (FE-1, 12 pcs.) for MF-50 filter unit

1

Replacement fuse (1.0 A)

1*

Mounting screws (M48)

3

Outlet spacer

1

Mounting plate1

Test stick

2 *3

Instruction manual (this document)

1 *4

PS-7 gas detector’s operation manual for administrators

2

1 *4

(Doc.No.GAE-019-xx)

1 *5

PS-7 pyrolyzer’s operation manual (Doc.No.GAE-020-xx)*1. Specified during order placement. Unspecified orders ship with R1/4- ø6 ㎜.
*2. Replacement fuse.
*3. Two pcs. per system.
*4. One pc. per system.
*5. One pc. is provided per system including a sensor unit with a pyrolyzer.
Note: Sensor units are sold separately, and not included in “Standard contents”.
Table 2. Optional items (sold separately)
Item Name

Qty.

Filter unit (MF-51)*6

As ordered.

Gas collector (PF-D1)

As ordered.

*6. Recommended when monitoring adsorbable gas (e.g. HCl, Cl2, NH3) otherthan HF and F2.

-4-

4. Block Diagram
MF-50 (filter unit)

Sampling unit
Sensor

Gas inFS

Rc 1/4

Ethernet signal
Power
24 VDC
Analog output
4-20mADC
Earth terminal
Trouble alarm open collector output

Rc 1/4

TB1

+
P
N +
G
H
E
TA
TC

Controller

COMM
board

RJ-45

PW Main unit
SW PW SWF2

CPU board
PW
TR
AL

+

Trouble alarm-

Maintennce

TB2

RS-485 signal

Gas outFlowseneorGAS IN
Rc 1/4
PoE power

Pump
P

A
B

Jack

SW

RS485A

Membrane
SW panel

RS485BGND

Gas alarm contact output (N.O.)

1st stage alarm

LCD

2nd stage alarm
CommonMax. load: 30 VDC 0.5 A (resistive load) for gas alarm contact (ZA1 or ZA2-ZC)
Max. load: 30 VDC 30mA (resistive load) for trouble alarm open collector output (TA-TC)

WARNING Turn off the gas detector before starting wiring to prevent electric shocks.
 Ground the gas detector to prevent electric shocks.
 Ensure open collector output is connected (TA: + / TC: -). Due to the built-in protection
diode, incorrect polarities will cancel an active trouble alarm output.

CAUTION The analog output line and power line of the gas detector are not isolated from eachother. When using with external devices, provide isolation to prevent noise from otherpower lines from interfering with the analog output of the detector.
 When wiring, place wires to avoid potential noise sources (e.g. large power transformers,
motors, and powers supply units).
 Ensure cables between the gas detector and external devices are connected correctly.

-5-5. Unit Dimensions and Components
5-1. Exterior Appearance
PS-7-M-01/02

1

Mounting pitch:

8

2
Mounting pitch:

4PS-7-M-03

6

3

5

8

7
Item

(Dimensions are in mm)

Component

Description/Function

1

Main unit

Includes a display, a pump and a sensor.

2

Base unit

3

Filter unit (MF-50)

4

Inlet spacer

Prevents the filter unit from being over tightened.

5

Latch (2 places)

Latches secure the main unit to the base unit.

6

White line (2 places)

Indicates that the latch is in the lock position.

7

Pyrolyzer

Refer to “PS-7 pyrolyzer’s operation manual” (separate document).

8

DIP switches

Thread cables thru the cable entry hole on the bottom of the baseunit and connect to the main unit
Incorporates a filter element (FE-1) that prevents dust from entering
the gas inlet and traveling into the sensor.

Used for setting IP address/unit ID and communication mode.
Refer to 5-4. “DIP Switches”.

-6-5-2. Main Unit

1

2

9

8

3

7
4
6
5

10

(Dimensions are in mm)

Item

Component

Description/Function

1

Green POWER LED

2

Amber TROUBLE LED

Flashing indicates an internal failure is present.

3

Red ALARM LED

Flashing indicates a gas alarm is present.

When lit, the unit is in normal operation mode(gas-monitoring mode).

Displays alarm notification, numeric gas concentration
4

LCD

value, gas concentration on bar graph, trouble status,
maintenance/test mode, and flow rate status.

5

Operation buttons (covered)

Setting/adjustment buttons and TEST switch.

6

Front cover

7

Front panel

Incorporates a built-in main board.

8

Sampling unit

Incorporates a built-in pump unit.

9

Rear coverProtects a built-in sensor unit.

10

Sensor unit

Remove the rear cover to remove/install a sensor unit.

Gently pull out and slide down to access the operation
buttons.

-7-

5-3. Base Unit
3

1

2

12
4

4

6

5
9

3

7

10

11
8

Item

Component

Description/Function

1

Fuse

Internal circuit protection.

2

Base unit power switch

Turns on/off the base unit.

3

Mounting hole

φ5.5 mm4

Terminal block (2 places)

Used for external wiring.

5

Main unit power switch

6

Maintenance switch

7

Pyrolyzer connector8

Gas inlet

9

Gas outlet

Thread size: Rc1/4

10

GrommetHolds signal and power cables.

11

RJ-45 jackConnect a LAN cable to the RJ-45 jack.

Turns on/off the main unit. Note: If the base unit powerswitch is off, no power is supplied to the main unit.
Switches between the maintenance mode 1 (MNT1),
maintenance mode 2 (MNT2), and normal operation mode.
Supplies power to a connected pyrolyzer (CDP-7).
Thread size: Rc1/4
Filter unit (MF-50) is attached to this inlet.

Turns on/off the terminal resistor.
12

Terminal resistor switch

Set the switch to the ON position to connect both ends ofthe circuit. Refer to “PS-7-M communication specifications
guide” (separate document).

-8-

5-4. DIP Switches

CAUTION Set the base unit power switch to the OFF position before using the DIP switches to avoid
incorrect operation or device failure.
 Do not use IP address “255 (1111 1111)” because LAN Communication will be disabled ifthat IP address is used.
 Set the DIP switches in accordance with your selected communication method. Refer tothe PS-7-M communication specifications guide for details.
 Ensure that each switch is clearly set to the 1/0, DY/ST, and Ethernet/RS485 positions.
Unclear setting may result in incorrect operation/communication.

NOTE

 The IP address settable range is 1 (0000 0001) to 254 (1111 1110).
 When the IP address is “0 (0000 0000)”, it will be superseded by the IP
address set by a web browser.
 IP address can be set to any value within the settable range, but if the same
address is used by more than one detector, the relevant detectors cannot
communicate.
The IP address settable range is 1 to 254.

1
Item
1

2

3

4

2

3

4

Component

Description/Function

Set the IP address for this product.
IP Address setting Settable range: 1 (0000 0001) to 254 (1111 1110).
switches Modbus TCP (Ethernet): Set the 4th value of IP address. *1
 Modbus RTU (RS-485): Set the unit ID.
Switches the IP address method between DY and ST.
IP address type
DY: Dynamic IP address (DHCP)
switchST: Static IP address
Switches the mode between Ethernet and RS485.
Mode change
ETHERNET: MODBUS TCP
switch
RS485: MODBUS RTU (RS-485)
Indicates the unit and communication statuses.
1: When flashes, LAN cable is securely connected to RJ-45 jack.
2: When flashes, Ethernet and RS-485 communications are in
progress.
Status LED-1/2/3
3: Communication status between the base and main unit.
- When flashes, communication is normal (sending and receiving)- When steady, no response from the main unit.
- When not lit, no request from the base unit.

*1: When the IP address is “0 (0000 0000)”, the IP address can be changed by using a web browser.

-9-5-5. Operation Buttons

2

3

9

4

5

1

8

7

6

Opening front cover
Pull and slide down the front
cover to access the operation
buttons and TEST switch.
Front cover

Slide down

Pull open

Item

ComponentPanelmarking

Description/Function

SPAN button(Span adj. button)
ZERO button(Zero adj. button)
AL button(Alarm setting check button)

ZERO

4

COMM. button

COMM.

5

UP and DOWN buttons

UP/DOWN

6

Analog output checkconnector

CP

Dedicated connector to check the unit’s 4-20
mA analog output.

7

TEST switch

TEST

Sets the unit to the test mode.

8

Button for administrator use

9Communication connector

123

Performs span adjustment. For O2 sensor unit
(COS-7), 21%vol adjustment will be performed.
Performs zero adjustment for toxic/flammablegas sensor unit (CDS-7/CHS-7)
Used to check the alarm set values.

SPAN

AL

Imports data from a currently inserted sensor at
initial startup, etc.
Increase/decrease the parameter value.

(Administrator use)
CN

(Unused)- 10 -

5-6. LCD Indicator Icons
3

4

5

2
6

1

7
LCD

10
Item

9

8

Icon/Display

1

Numeric display

2

FLOW

3

ALARM1

4

SENS.

5

CONV.

Description/Function
Displays gas concentration and the unit of measurement.
E.g. %LEL, ppb, ppm
Flow rate is low. Linked with item 6.

ALARM2

1st and 2nd stage gas alarms.
A sensor fault (e.g. broken wire) is present or incorrect
sensor unit is inserted.
Broken pyrolyzer wire.
Represents the flow rate of sampled gas.
- Spinning fast: Flow rate is normal. “FL500" indicated on
sub-display.

6

Flow rate- Spinning slowly: Flowrate is reduced. Possible filter/tube
clogging. “FL400” or less indicated on sub-display.
- Stopped: Flow rate is too low. Low flow rate alarm.
“FL300” or less indicated on sub-display.

7

Gas concentration on bar
graph

One bar represents 5% of the full scale value. The bar
graph value increases from left to right with the far rightbeing full scale value.
Displays information on setting, flow rate, etc.

8Sub-display

9

TEST mode

Unit is in test mode.

10

MNT1 / MNT2 mode

Unit is in maintenance mode 1 or 2.

(Administrator use)

- 11 -

6. Installation and Wiring
DANGERThis product is not explosion-proof equipment and should not be installed in ahazardous area.

WARNING For detection of adsorptive gas (e.g. HF and F2), remove the filter element (FE-1) fromthe filter unit (MF-50). Correct detection is not possible if the filter element is present.
Refer to 9-1. “Filter Element Replacement”.
 Tubing should be Teflon, φ6/4, and less than 20m in length. For adsorptive gases(e.g. HF, F2, HCl, Cl2, NH3), the tube length should be less than 5m.
 Set the main unit power switch (located on the front of the base unit) to the OFF
position before installing/removing the main unit. Installation/removal while the main
unit power switch is in the ON position may cause a false alarm or device failure.


CAUTION Install the gas detector in a place free from impact and vibration.
 Do not install in the vicinity of equipment which can generate high frequencies or amagnetic field.
 Do not use a gas collector in a confined space (e.g. inside a duct).
 Do not install the gas detector in a high temperature (higher than 40ºC) and
condensation-prone area. Avoid sudden temperature changes.
 This product is not drip-proof equipment and should be kept away from splashingwater.
 Do not block the cooling vents on both sides of the base unit.
 The pressure differential between the gas inlet/outlet and the outside air pressure(atmospheric pressure) should be within 1kPa. In addition, the pressure differential
between the gas inlet and the gas outlet should be within 1kPa, with negative
pressure applied to the gas inlet. Using the detector under overpressure will cause an
excess flow, which may result in flow rate error or incorrect measurement.
 This unit is precision equipment. Stress or impact to the base unit should be avoided.
 Install the gas detector vertically with its gas inlet and outlet facing down.
 Determine the height for the tip of sampling tube by considering the specific gravity ofthe target gas, and install the gas detector where gas is expected accumulate.
Gas type

Installing heightGas heavier than air

Maximum of 30 cm above the floor

Gas near the specific gravity as air

75 to 150 cm above the floor

Gas lighter than air

Near the ceiling- 12 -

NOTE

 When installing the gas detector, ensure there is enough space
below/above the detector to allow for installation/removal/wiring activities.
(Recommended: More than 100mm above the unit and 150mm below theunit.)
 When installing more than one detector side by side, make sure to leave
enough space right and left to the gas detector to allow for
installation/removal of the main unit. (Recommended: More than 30mm
right and left to the unit.)

6-1. Wiring Procedure

WARNING Turn off the gas detector before wiring to prevent electric shocks.
Ensure open collector output is connected (TA: + / TC: -). Due to the built-in protection
diode, incorrect polarities will cancel an active trouble alarm output.

CAUTION The analog output line and power line of the gas detector are not isolated from eachother. When using the detector with external devices, provide isolation to prevent noisefrom other power lines from interfering with the analog output of the detector.
 When wiring, place wires to avoid potential noise sources (e.g. large powertransformers, motors, and powers supply units).
 Ensure cables between the gas detector and external devices are connected correctly.
 Gas alarm contact output is intended to be used with resistive loads only. If used withinductive loads, high voltage surge will be generated resulting in damage to the device
or relay contacts.
 Turn off the gas detector before fuse replacement.
 Keep the connection cables (power and signal lines from the detector) away from otherpower lines.
 When wiring, place wires to avoid mechanical stress on the wiring.

- 13 -

Marking
on board

Function *1

Polarity

P

+

N

-

G

+

Gas concentration output

H-(4-20 mADC)

Recommended cable *2

Power input (24 VDC)

E

2-core CVV cable

3-core CVVS cable

Earth terminal
Trouble alarm

TA+(Open collector: N.C.)
Max. load: 30 VDC, 30mA resistive load

TC

-

A

+

B

-

2-core CVV cable

Trouble alarm, Common
2-core shielded twisted paircable

Digital signal (RS-485)

GND
1st stage gas alarm contact output
ZA1(Dry N.O. contact)
Max. load: 30 VDC 0. 5 A resistive load
2nd stage gas alarm contact output

ZA2

3-core CVVS cable(Dry N.O. contact)
Max. load: 30 VDC 0. 5 A resistive load

ZC

ZA1, ZA2 Common*1. N.C. Normally Closed. N.O. Normally Open.
*2. Applicable cable: Dia. 8-11mm x 2pcs. Use appropriate cables for the installation environment.

A
RS-485 signal

B
GND

Gas alarm
contact outputs

+

P

－

N

+

G

－

H

ZA1

+
-

24 VDC input
入力+-

4-20mA output+-

Trouble alarm

E
(FG)

ZA2

+

ZC
－

Terminal layout- 14 -

TATC

6-1-1 Modbus TCP (Ethernet) Wiring Procedure
Establishing Modbus TCP communication

WARNING When using the 24 VDC power supply, ensure that the power is 24 VDC 10%.
 When using the PoE power supply, ensure that the LAN cable is securely connected.

When PoE-HUB is connected,(1) Insert a LAN cable to the RJ-45 jack located at the bottom of thebase unit.

CAUTION
Turn off the PoE before disconnecting the LAN cable from the
RJ-45 jack.

RJ-45 jackGrommet(2) Run a signal cable thru the grommet (located at the bottom of the base unit), and connect
the cable wires to their corresponding terminals (refer to “Terminal layout” on page 14).
When 24VDC power supply is used without a connected PoE-HUB(1) Insert a LAN cable into the RJ-45 jack located at the bottom of the base unit.
(2) Run power and signal cables thru the grommet (located at the bottom of the base unit), andconnect the cable wires to their corresponding terminals (refer to “Terminal layout” on page 14).

6-1-2 Modbus RTU (RS-485) Wiring Procedure
Establishing Modbus RTU (RS-485) communication

WARNING When using the 24 VDC power supply, ensure that the power supply is 24 VDC 10%.

CAUTION Applicable cables: Dia.8-11mm x 2pcs. Use appropriate cables for the installation
environment.

- 15 -

(1) Run a power cable thru the grommet (located at
the bottom of the base unit), and connect thecable wires to their corresponding terminals(refer to “Terminal layout” on page 14).
(2) Run a RS-485 digital signal cable thru thegrommet (located at the bottom of the base unit),
and connect the cable wires to theircorresponding terminals (refer to “Terminal

Terminal
block forsignalcable

Terminal
block for
power
cable

layout” on page 14).

 Use shielded twisted pair cable for RS-485 wiring. Cable length: Max.1.2 km

NOTE Single-point grounding (grounding at a single point) is mandatory. When thecable shield from the gas detector is grounded on the power supply side, DO
NOT ground the shield cable to the Earth terminal located inside the gas
detector (on the terminal block for power cable) to avoid 2-point grounding..
Requirements for LAN cable Use unshielded twisted pair (UTP) LAN cable, solid wire, category 5e or
higher.
 Do not use a flat type twisted pair LAN cable.
 If used in a place exposed to electrical noises, use a shielded twisted pair
(STP) cable for added resistance to external interference.
 Cable length: Max.100 m
 Refer to the separate PS-7-M communication specifications guide.

- 16 -

6-2. Unit Installation Procedure
1.

Determine where to place the base unit (positioning). Secure the mounting plate to the wallwith the two mounting screws (M4x8).

2.

Anchor the base unit to the mounting plate by inserting the mounting plate into the slot onbottom of the base unit, and secure using the mounting screw (M4x8).
Mounting screw

Mounting screws
Pitch

3.

Mounting plate

To install the sensor unit at this time, refer to 9-2. “Sensor Unit
Installation/Replacement”.
To install the sensor unit at later stage, move to step 4.

4.

Ensure that the main unit power switch is in the OFF position.

5.

To install the main unit, pull forward and hold both latches of theRail

Pull latches forward.

base unit. Connect the main unit by sliding it onto the rails of thebase unit.

Fully push latch (lock position).

6.

Push the base unit’s latches back into place so that the whitelines are visible, indicating the latches have been locked.

White line

Latch

WARNING Ensure that the latches are in the fully locked position (white lines visible). Normal
detection is not possible if the latches are not fully locked.

- 17 -

6-3. Tube Fitting Connection Procedure
Install the provided half union tube fitting into the filter unit inlet and gas outlet.

CAUTION
 Over tightening the filter unit inlet may break the gas inlet. When connecting theprovided half union to the filter unit inlet, secure the filter unit inlet with one adjustablewrench or spanner, etc. to prevent filter unit inlet from rotating and another to install thehalf union.
Gas inlet
Secure the filter unit
inlet with adjustablewrench, etc.
Rotate the half union withadjustable wrench, etc.

When metal tube fittings (not provided) need to be installed into the filter unit inlet and gas outlet.

CAUTION
 Over tightening metal tube fittings may break the gas outlet. To prevent this, install theprovided gas outlet spacer to the gas outlet first, then connect the metal tube fitting
over the spacer.
 Use metal tube fittings (Swagelock SS-6MO-1-4RT or equivalent) for both gas inlet andoutlet.
 Wrap sealing tape tautly around the threads of each metal tube fitting to prevent slack(approx.2.5 wraps).
Tape size: 13mm (width) x 1005mm (length) x 0.1mm(thickness)
Tighten the metal tube fitting until hand-tight. Do not over tighten the tube fitting or thegas outlet may break.
Gas outlet
Outlet spacer

Metal tube fitting(Swagelock SS-6MO-1-4RT)- 18 -

7. Operation
7-1.Operation Procedure
Operation Flow
Corresponding numbered steps are given for items1 to 13 on the following pages.
Initial startup

1. Set the IP address/Unit ID.

PW 24 VDC

2. Is the power
voltage/current
24VDC±10％?
Yes

No

Select the power
supply.

 Check the powersource.
 Check the wiring to
the terminal blocks.

PoE Disconnect andconnect LAN cable.
 Check the powersource (PoEHUB).

2. Is LAN cablesecurely connected?

No

Yes

3. Turn on the base unit.

１No
Do you detect toxic or
combustible gas?

Amber TROUBLE
LED flashes.

Low oxygen detection

8. Incorrect sensor unit
is inserted.

8. Self-test

Yes

Amber TROUBLE LED is off.

4. Adjust the analog output
for Maintenance mode 2.

4. Adjust the analog output
for Maintenance mode 2.

Set value change is needed.
10. Check the set
Change the set values.
values.
の確認
No set value change is needed.

Base unit startup is completed.

No
5. Is the sensor unit
installed?

Abnormal
11.12. Check the
Check the tubing for looseness.
sampling gas for flowrate and airtightness.

Install the sensor unit.

Yes

NormalNo

Is the main unit off?

No
13. Is this for
toxic/combustible gas
detection?

Turn off the main unit.

Yes

Yes

6. Install the main unit.

7. Turn on the main unit.

12. Is this for low
oxygen detection?

13. Perform zero adjustment.

13. Perform 21vol% adjustment.

14. Initial startup is completed.
１- 19 -

Operation Steps
Operate the gas detector by taking the following steps.

WARNING When using the 24 VDC power supply, ensure that the power is 24 VDC 10%.
 When using the PoE power supply, ensure that the LAN cable is securely connected.
 Check that the target gas type and full scale value are correct before using a new sensor
unit. Also, check that the sensor unit expiration date has not been reached.


CAUTION

Before turning on the gas detector, check that all wiring is correct. Refer to 6-1. “Wiring
Procedure” and your delivery specifications if your unit has end-user-specific options.

Set the IP address/Unit ID.

1.

Modbus TCP communication requires that the 4th value of the IP address to be set.
RS-485 communication requires the Unit ID (slave address) to be set.
Remove the address plate to access the DIP switches and set the IP address or Unit ID.

Address plate

Pull the center of the plate with finger
to remove it from the base unit.

DIP switches are accessible when
the plate is removed.

CAUTION

Set the base unit power switch to the OFF position before using the DIP switches toavoid incorrect operation or device failure.

Do not use IP address “255 (1111 1111)” because LAN Communication will be disabled ifthat IP address is used.

- 20 -

 The IP address settable range is 1 (0000 0001) to 254 (1111 1110).

NOTE

 When the IP address is “0 (0000 0000)”, it will be superseded by the IP
address set by a web browser. Refer to "PS-7-M IP address setting guide”(separate document) for IP address change.
 IP address can be set to any value within the settable range, but if the same
address is used by more than one detector, the relevant detectors cannot
communicate.
 Ensure that each DIP switch is clearly set to 1 or 0 position. A switch in an

unspecified position will cause unintended setting and incorrect
operation/communication.
 Refer to “PS-7-M IP address setting guide” (separate document) for full
information.
To set the address with a web browser:
It is possible to set/change the IP address by using a web browser. Refer to “PS-7-M IP address
setting guide” (separate document) for full information.
To set the address with the gas detector:
Setting procedure is as follows.
(1)

Set the right two DIP switches

1 to “ST" (Static IP address) and “ETHERNET”(Modbus TCP communication) respectively.
(2)

Set the 4th value of the IP address by using the left eight DIP switches

2 .

The IP address is entered in binary form. E.g. “0000 1001” = “9”

2

2.

1

When 24 VDC power supply is used
Check that the power voltage (between P and N on the terminal block) is 24 VDC 10%.
When PoE is used
Check that the status LED-1 flashes.
Note: The status LED-1 is off when the LAN cable isnot securely connected.

Status LED-1- 21 -

3.

Set the base unit power switch to the ON position.

Base unit power switch

4.

Power ON

Adjust the analog output for the maintenance mode 2 (MNT2).
The maintenance mode 2 analog output varies depending on the sensor unit type. Therefore,
the output needs to be adjusted by taking the following steps. Refer to 7-5. “Operation -Maintenance Mode” for full information on the maintenance mode.
(1) Lift the cover flap open. Set the maintenance switch to the MNT2 position.
To MNT2 position

Lift the cover flap open.

(2) Adjust the analog output level.
Toxic gas sensor (CDS-7)

Oxygen sensor (COS-7, FS: 50vol%)Combustible gas sensor (CHS-7)
Oxygen sensor (COS-7, FS: 25vol%)Measure the analog output (current)

Measure the analog output (current)

between the “G” and “H” terminals with

between the “G” and “H” terminals with aa multimeter, etc.

multimeter, etc.

If the output level is within the range

If the output level is within the range

below, go to step (3). If not, adjust it

below, go to step (3). If not, adjust it using

using the trimmer.

the trimmer.

Sensor unit model

Adjustable range

Sensor unit model

Adjustable range

CDS-7

3.92-4.08mA

COS-7 (FS: 50%)

10.64-10.80mA

CHS-7

3.92-4.08mA

COS-7

17.32-17.48mA- 22 -

Trimmer (adjustment screw)
Rotate the trimmer with a slotted screwdriver to adjust+G

the MNT2 output level.

H

NOTE
Toxic gas sensor (CDS-7)
Combustible gas sensor(CHS-7)
Analog output

Gas level

20mA

Full scale

Oxygen sensor(COS-7, FS: 25vol%)Analog output

O2 level

Analog output

O2 level

20mA

25vol％

20mA

50vol％

17.4mA

21vol％

10.7mA

21vol％

4mA
4mA

0ppm

0mA

Oxygen sensor(COS-7, FS: 50vol%)0％0mA
Normal air has an O2 level of
21vol%. Adjust to 17.4mA.

4mA

0％

0mA
Normal air has an O2 level of
21vol%. Adjust to 10.7mA.

(3) Set the maintenance switch to the center position (normal operation mode).
To center position (normal mode)

Lift the cover flap open.

5.

Install the sensor unit if it is not installed yet. For installation procedure, refer to 9-2. “Sensor
Unit Installation/Replacement”. Ensure the main unit power switch is in the OFF position
before sensor unit/main unit installation.

6.

Install the main unit to the base unit. For installation procedure, refer to 6-2. “Unit Installation
Procedure”.

- 23 -

7.

Set the main unit power switch to the ON position.

To ON position

Lift the cover flap open.
Main unit power switch

8.

All the LEDs on the front and the LCD turn on for one second, then the gas detector starts
self-test.

When this product is used for the first time or a different gas type/setting of sensor unit isinstalled (e.g. target gas or full scale value is different), the TROUBLE LED will flash, SENS.
will appear and “Err” will be shown on the sub-display. Open the front cover and press theCOMM. button for more than one second to clear the error.
TROUBLE LED flashing

COMM. button

When the same type/setting of sensor unit is installed (e.g. target gas and full scale value are
the same as the previous one), go to step 9.

9.

“Good” is shown on the sub-display. The unit will begin a 30-second initialization mode
(POWER LED flashes), then start normal operation mode (POWER LED is steady lit) with thegas concentration displayed on the LCD.
Green POWER LED
30 sec flashing  steady lit- 24 -

10. Check the set values.

Note: To change the set values, refer to the “PS-7 gas detector’s operation manual for
administrators” (separate document).
To view the set values shown in the table below, press the UP/DOWN button.
Press the UP/DOWN button to cycle through the items in the sequence shown in the table.
The set value for the selected item is displayed on the sub-display (bottom right).

On sub-display

Function to set

d1 ＊＊Delay time 1

d2 ＊＊Delay time 2

az
as

Analog output (zero)
Analog output (span)zs ＊Zero or 21vol%suppression

H-H
L-L
H-L

Gas alarm mode

Con ＊
CG ＊＊

Broken pyrolyzer
wire detected
Calibration gas
concentrationnEt ＊Comm. settingF ＊＊＊F valueFL＊＊＊

Flow rate

P ＊＊＊Sensor unit output
Automatic 21vol%adjustment

At ＊Description/remarks
Delay time for 1st stage
gas alarm contact (sec)Delay time for 2nd stage
gas alarm contact (sec)*1*1
Suppression percentage
against full scale value(in 1% increments)
High-High limit
Low-Low limit
High-Low limit
0: Detected.
1: Not detected.
*1
Disabled (setting cannot
be changed).
*1
The current flow rate isdisplayed. (mL/min)*1
0: Disabled
1: Enabled*1. For New Cosmos service engineer use.

- 25 -

Default setting
Toxic: CDS-7
Combustible:
O2: COS-7
CHS-7
d1 0

d1 0

d2 0

d2 0

-

-

zs 5

zs 2

H-H

L-L

Con 0

Con 0

CG 40

CG 84

nEt 1

nEt 1

-

At 1



To view each gas alarm set value, press the AL button.
Press the AL button to cycle through the items in the sequence shown below.
A1 ＊＊  A2 ＊＊ (normal operation mode)  A1 ＊＊  A2 ＊＊
The percentage in full-scale% is shown on the sub-display (bottom right corner).
E.g. “A1 10” represents that the 1st alarm set value is 10% of the full scale value.
The actual alarm set concentration value is shown on the LCD.
E.g. 0.10 ppm
On sub-display

Default set value
Toxic: CDS-7

A1 ＊＊Combustible: CHS-7
O2: COS-7
Toxic: CDS-7

A2 ＊＊Combustible: CHS-7
O2: COS-7

Description

A1 10

10% of full scale value

A1 72

72% of full scale value

A2 20

20% of full scale value

A2 76

76% of full scale value

AL button

LCD
E.g. 0.10 ppm
Sub-display
E.g. A1 10

UP/DOWN button

11. Check for the correct sampling gas flow rate.
Check that the flow rate icon quickly spins and the amber TROUBLE LED is off.

When the flow rate icon is quickly spinning, the specified flow rate (500mL/min) is
maintained.
Amber TROUBLE LED is off.

- 26 -

Flow rate icon quickly
spinning.

NOTE

Clogging notification
Slowly spinning

The flow rate icon slowly spins when the flow rate is
reduced (less than 400mL/min), indicating a possible
clogged tube/filter, or excessive negative pressure, etc.
Gas detection and gas-monitoring continue even when thisgas notification is present.

Stops spinning

Low flow rate alarm notification
When the flow rate is too low (300mL/min or less), the flowrate icon stops and FLOW is shown on the LCD. The
amber TROUBLE LED flashes and a trouble alarm isactivated.

12. Check for the airtightness.

Disconnecting the tube from the gas inlet and fully blocking the inlet with a finger willchange the flow rate icon’s spinning speed from quick to slow. Keep blocking it, andcheck that the flow rate icon stops spinning and the amber TROUBLE LED starts flashing.
(The delay time for the low rate alarm is set to 10 seconds.) The FLOW appears on the
LCD.
If the flow rate icon stops spinning, but the amber TROUBLE LED does not flash, checkthat the sensor unit is installed into the main unit completely. Refer to 9-2. “Sensor Unit
Installation/Replacement”. Check that the latches are in the fully locked position (whitelines visible).
Connect the tube back to the gas inlet. Check that the flow rate icon quickly spins.

Block gas inlet- 27 -

13. One-touch zero/21vol% adjustment(Zero adjustment for CDS-7, CHS-7 and 21vol% adjustment for COS-7)
Take the steps in the table below, to perform one-touch zero/21vol% adjustment once thespecified period of time passes after turning on the main unit. Repeat the one-touch
zero/21vol% adjustment to increase the accuracy.
Sensor unit type
Toxic gas:
CDS-7
Oxygen gas:
COS-7 (25vol%)Combustible
gas: CHS-7

NOTE

Timing for
1st adjustment

Timing for2nd adjustment

Steps

30 minutes after
powering-up

24 hours after
powering-up

Set the maintenance switch to MNT1
or MNT2. Press the ZERO button.
Set the maintenance switch to MNT1
or MNT2. Press the SPAN button.

One day after
powering-up

7days after
powering-up

Set the maintenance switch to MNT1
or MNT2. Press the ZERO button.

 Depending on the environment, it may take longer than the expected 24 hour/7
day period (see above) for the base line (zero or 21vol%) to be fully stabilized.
 For COS-7 oxygen sensor (FS: 50vol%), one-touch 21vol% adjustment is notpossible. However, if 21vol% adjustment is needed, refer to “PS-7 gas
detector’s operation manual for administrators” for the procedure (separate
document).

WARNING
Perform zero/21vol% adjustment in clean air. Inaccurate gas concentrations will be
indicated if the zero/21vol% adjustment has been done in a contaminated gas
atmosphere.

CAUTION
When switching the maintenance switch from MNT1 to MNT2 or vise versa, the gas
detector briefly enters the normal operation mode. If switching is done while an alarm
condition exists, an alarm signal will be output. If the alarm contacts/open collector areused to operate the interlocks of the external devices, release the interlocks beforehand,as needed to prevent a possible activation of the interlocks during switching themaintenance switch.
Procedure(1) Set the maintenance switch to MNT1 or MNT2 position. Refer to 7-5. “Maintenance Mode
Setting/Operation” for more information.
Set to MNT or MNT2

Lift the cover flap open.

- 28 -

(2)Toxic gas sensor (CDS-7)

Oxygen sensor (COS-7)

Combustible gas sensor (CHS-7)
Press the ZERO button for more than 2

Press the SPAN button for more than 4seconds. The green POWER LED willseconds. The green POWER LED will

flash

flash one time, indicating the zero

one

time,

indicatingtheadjustment is completed.

zero

adjustment is completed.

POWER LEDSPAN button
ZERO button(3) Set the maintenance switch to the center position (normal operation mode).
Set to the center position

Lift the cover flap open.
(4) Perform zero/21% adjustment again by repeating the steps (1) to (3) at the following
timing:

24 hours after powering-up for toxic gas and oxygen
7 days after powering-p for combustible gas

14. Affix the target gas sticker to the front (visible location) of the detector.
Green POWER LED is on.
Amber TROUBLE LED is off.
Red ALARM LED is off.
Gas concentration with
In normal operation with no alarm
unit of measurement(%LEL, ppb, or ppm)
Target gas sticker

Flow rate icon quickly
spinning- 29 -

Normaloperation(gasmonitoring)
Green lit

Trouble alarm(internal failure)

1st stagegas alarm

2nd stagegas alarm

Amber flash

Red flash

Red flash

FLOW
SENS.
CONV.

ALARM1

ALARM1
ALARM2

LED

LCD
Gas alarm
contact (ZA1)
Gas alarm
contact (ZA2)
Trouble alarm
open collector
(TA)

OFF
(open position)OFF(open position)ONON(closed position)(closed position)OFF(open position)OFF(open position)OFF(open position)(closed position)

ON

OFF(open position)ONON(closed position)(closed position)(closed position)ON

7-2. Operation - Gas Alarm
If the gas concentration exceeds the gas alarm set value, the alarm contacts will activate after thealarm delay time, the red ALARM LED will start flashing, and ALARM1 or ALARM1 ALARM2 will
be shown on the LCD.
Note: During the alarm delay time, ALARM1 or ALARM1 ALARM2 flash, the alarm contact does
not activate, and the red ALARM LED does not flash.
Self-resetting: When the gas concentration falls below the gas alarm set value, the ALARM LED,
ALARM1 ALARM2 and relevant gas alarm contacts will automatically return to their normal
positions/status.
The table below lists the operation of each mode in the event of a gas alarm.

1st stage gas alarm

2nd stage gas alarm- 30 -Red ALARM LED flashingOn display

1st stage gas alarm

2nd stage gas alarm

NOTE

ALARM 1
ALARM 1
ALARM 2

Green

Amber

Red

POWER LED

TROUBLE LED

ALARM LED

On

Off

Flashing

On

Off

Flashing

A1 and A2 relation in each gas alarm mode
 H - H mode (High-High limit alarm)
Full scale
2nd stage gas alarm:

ALARM1 and ALARM2 are lit.
Gas alarm contacts (ZA1, ZA2) activate.
Alarm set value shown as “A2 ＊＊”.
1st stage gas alarm: ALARM1 is lit. Gas alarm contact (ZA1) activates.
Alarm set value shown as “A1 ＊＊”.

0ppm

Reading in normal ambient air (no gas detected)

 L - L mode (Low-Low limit alarm)
25vol％
21vol％

Reading in normal ambient air (no gas detected)
1st stage gas alarm:

ALARM1 is lit. Gas alarm contact (ZA1) activates.
Alarm set value shown as “A2 ＊＊”.

2. nd stage gas alarm:

ALARM1 and ALARM2 are lit. Gas alarm contacts (ZA1, ZA2) activate.
Alarm set value shown as “A1 ＊＊”.

0vol％

 H - L mode (High-Low limit alarm)

50vol％

21vol％

0vol％

High limit of gas alarm: ALARM2 is lit. Gas alarm contact (ZA2) activates.
Alarm set value shown as “A2 ＊＊”.
Reading in normal ambient air (no gas detected)
Low limit of gas alarm: ALARM1 is lit. Gas alarm contact (ZA1) activates.
Alarm set value shown as “A1 ＊＊”.

- 31 -

7-3. Operation - Trouble Alarm
This unit can detect an internal failure. When an internal failure is detected, a trouble alarm will
activate (open collector is normally ON (closed position) and during a trouble alarm switches to
OFF (open position). The amber TROUBLE LED will start flashing, and the analog output will fall
to 0.6mA or less.
Self-resetting: When a problem is removed, the TROUBLE LED, open collector, and analog output
will automatically return to their normal positions/status.
Please refer to 10. “Troubleshooting”, as well.
Internal failures include:(1) Low flow rate
When a minimum flow rate is not present, the unit determines the flow rate is too low. The
FLOW is shown on the LCD and the spinning flow rate icon stops. The causes of a low flowrate include: clogged filter element, clogged tubing, excessive negative pressure, wornpump.
(2) Sensor fault
SENS. appears on the LCD in the following situations:- the sensor’s zero level output is extremely low.
- a broken sensor wire is detected. This applies to combustible gas sensor (CHS-7) only.
(3) Incorrect sensor installed
The data (e.g. target gas type, full scale value) from the last installed sensor has beenrecorded by the gas detector. If a newly installed sensor unit does not match, the gas
detector will detect that an incorrect sensor unit is installed, and display the SENS. and“ - - - -“ on its LCD. To use a newly installed sensor unit which does not match the previous
sensor type, press the COMM. button to renew the data.
(4) Broken pyrolyzer wire (when detector uses a pyrolyzer)
If a broken wire is detected, CONV. will appear on the LCD.
(5) No power
If the gas detector is not powered, all the LEDs will turn off and the detector will stop
operation.
(6) Blown fuse
If the fuse blows, causing the unit to lose power, then all the LEDs will turn off and thedetector will stop operation.
(7) Memory read error
When the internal memory cannot be read normally after powering-up, “nG” will be shownon the LCD.

- 32 -

CAUTION
Oxygen sensor (COS-7): The analog output from this product falls to 0.6mA or less in theevent of a trouble alarm as listed above. When the host system (e.g. control room) is set to the
low limit alarm (gas alarm activates when the gas concentration falls to the alarm set value orless) and If the product’s analog output falls to 0.6mA or less in under a second without a gas
alarm, then it means that a trouble alarm is present. Take measure to prevent the host systemfrom activating a gas alarm, as needed.

Green
POWER
LED

TROUBLE

LED

Red
ALARM
LED

FLOW

On

Flashing

Off

SENS.

On

Flashing

Off

Trouble(internal failure)

On display(1)

Low flow rate(2)

Sensor fault

Amber

(3)

Incorrect sensor
installed

SENS.

On

Flashing

Off(4)

Broken pyrolyzer
wire

CONV.

On

Flashing

Off(5)

No power

Off

Off

Off

(6)

Blown fuse

Off

Off

Off

(7)

Memory read
error

On

Flashing

OffnG- 33 -

Remarks
Flow rate icon
stops spinning.
“- - - -“shown for the gas
concentration on
the LCD.

Error code
shown on the
sub-display.

7-4. Operation - Test Mode
Setting
Press the TEST switch with the test stick to enter the test mode.
Each press of the recessed TEST switch will turn on and off the test mode. The test mode willautomatically end in10 minutes.

Increase/decrease the analog output value
using UP/DOWN button.

Turn on/off TEST switch with test stick.

Operation“TEST” will be shown on the LCD.
While in test mode, it is possible to change the analog output (4-20mA) to a desired value in
0.16mA increments (1% of the full scale value). Increase or decrease the analog output value bypressing the UP or DOWN button.

CAUTION

While in test mode (alarm test using TEST switch), the gas alarm contacts activate. If
the gas alarm contacts are used to operate the interlocks of the external devices,
release the interlocks beforehand, as needed to prevent a possible activation of theinterlocks during the test mode, orenter the maintenance mode before entering the test mode, then release the interlocksof the external devices beforehand as needed. (Refer to 7-5. “Operation - Maintenance
Mode” for more information).
Notify those concerned before starting the gas alarm test.

While in maintenance mode, the status information of gas/trouble alarms is sent to thehost system (e.g. control room) digitally. If the gas alarm contacts/trouble alarm open
collector are used to operate the interlocks of the external devices, release theinterlocks beforehand, as needed to prevent a possible activation of the interlocks
during the maintenance mode.

- 34 -

7-5. Operation - Maintenance Mode
Setting
The maintenance switch has three modes, maintenance mode 1 (MNT1), maintenance mode 2(MNT2), and normal operation mode (gas monitoring mode).
Set the maintenance switch to MNT1 or MNT2 on the base unit’s front. “MNT1” or “MNT2” will beshown on the LCD. To return to the normal operation mode, set the maintenance switch to thecenter position.

MNT1 – normal operation – MNT2
(center)

Maintenance switch Lift the cover flap open.

Operation
During MNT1, gas alarm contacts and trouble alarm open collector are disabled.
During MNT2, gas alarm contacts and trouble alarm open collector are disabled, and the analog
output is fixed at 4.0mA (or 17.4mA for oxygen).
In either maintenance mode, the amber TROUBLE LED will flash and the detected gas
concentration will be shown on the LCD.

MNT1 (hostmaintenancemode *3)

MNT2

Gas alarm
contact

Trouble alarm
open collector

Disabled

Disabled *1(fixed at OFF)(fixed at ON)

Disabled

Disabled *1(fixed at OFF)(fixed at ON)

Analog output

Amber
TROUBLELED

On display

Outputcorresponding to
the detected gas
concentration.

Flashing

Detected gas
concentration
value

Fixed at 4.0mA or
17.4mA *2

Flashing

Detected gas
concentration
value

WARNING

During normal operation (gas monitoring), ensure the maintenance switch is set to thecenter position. Gas alarm contacts and trouble alarm open collector do not activate
during MNT1/MNT2. When the maintenance switch is set to MNT2, the analog output isfixed at 4.0mA or 17.4mA.

- 35 -

CAUTIONWhile in maintenance mode, the status information of gas/trouble alarms is sent to thehost system (e.g. control room) digitally. If the gas alarm contacts/trouble alarm open
collector are used to operate the interlocks of the external devices, release theinterlocks beforehand, as needed to prevent a possible activation of the interlocks
during the maintenance mode.

When switching the maintenance switch from MNT1 to MNT2 or vise versa, the gas
detector briefly enters the normal operation mode. If switching is done while an alarm
condition exists, an alarm signal will be output. If the alarm contacts/open collector
are used to operate the interlocks of the external devices, release the interlocks
beforehand, as needed to prevent a possible activation of the interlocks duringswitching the maintenance switch.

*1. Trouble alarm will activate if the main unit power switch is set to the OFF position during
MNT1 or MNT2 mode. (OFF)*2. The analog output may change when the main unit power switch is set to the OFF position.

NOTE

 Maintenance mode 1 and 2 is available with the base unit without a main unit.
The base unit can produce a 4.0mA or 17.4mA analog output while inmaintenance mode 2. This function is useful for loop check at startup, etc.
*3. It is possible to set/cancel the maintenance mode (“host maintenance mode”)
from the host system/device via the base unit using Modbus communication.
The operation of the host maintenance mode is the same as maintenancemode 1.

- 36 -

8. MaintenanceThis gas detector requires no on site gas calibration. Each sensor unit has been gas-calibrated
when shipped. Replace the sensor unit with a new one every 6 months except for combustible gas
sensor units (CHS-7). The CHS-7 is divided into two types, hot-wire combustible (CH) andcatalytic (CS). Sensor life of CH and CS types are 5 and 3 years from the installation daterespectively.
Routine checks are carried out by the user. 6-month and 3-year periodic inspections are
performed by the user, New Cosmos or its authorized representative.
Record check/inspection results and save them for at least 3 years. Example of thecheck/inspection results is on page 39.

Important Maintenance Notice
In order to ensure the reliability of the gas detector, it is vital to perform periodic sensor unit
replacement. The replacement can be done by the user, but it is highly recommended that amaintenance contract with a local New Cosmos representative be made for the performanceof periodic sensor unit replacement and inspection.

Inspection Contents and Frequency
Check item

Startup or
relocation

Periodic Inspection
Every 6 months Every 3 years(1) Concentration display

VV(2) Sampling gas flow rateVV(3) Airtightness

VV(5) TubingV(6) Sensor unit
installation/replacement

VVV(7) Sampling unit replacement(8) Loop check and alarm test
using TEST switchVV(4) Filter element

VV- 37 -

Routinecheck(1) Concentration display
Check that the gas concentration value is shown on the LCD and the detector is operating.
Green POWER LED is on.
Amber TROUBLE LED is off.
Red ALARM LED is off.
Gas concentration
with unit of measurement(%LEL, ppb, or ppm)
Flow rate icon quickly spins.

(2) Sampling gas flow rate
Check that the flow rate icon (on the right top corner of the LCD) is quickly spinning.
Refer to 7-1. 11 “Check for the correct sampling gas flow rate”
When the flow rate icon slowly spins or stops, check the filter element for contaminants. If thefilter element (FE-1) is dirty, replace it with a new one. Refer to 9-1.“Filter Element
Replacement” for procedure. If the flow rate icon returns to normal operation (quickly spinning),
check the tubing for clogging or excessive negative pressure.
(3) Airtightness
Check the airtightness of the unit by referring to 7-1.12. “Check for the airtightness..”(4) Filter element replacement
Check the filter element for contaminants at least once every 6 months and replace as needed.
The filter element is likely to clog faster in severe environment. If the clogging notification (flowrate icon slowly spins or stops) appears on the LCD, check the filter element. Replace it with a
new one, if it is dirty. Refer to 9-1. “Filter Element Replacement” for procedure.
(5) Tubing
Check that tubing has been done correctly at startup or relocation. If the tubing is incorrect, gas
sampling from the target place is not possible and an appropriate flow rate cannot be
maintained.
(6) Sensor unit installation/replacement
Install a new sensor unit into the gas detector at startup. Replace it with a new one every 6months except for combustible gas sensor units (CHS-7). CHS-7 is divided into two types,

hot-wire combustible (CH) and catalytic (CS). The sensor life of CH and CS types are 5
and 3 years from the installation date respectively. For procedure, refer to 9-2. “Sensor Unit
Installation/Replacement”.

- 38 -

(７) Sampling unit replacement
Replace the sampling unit with a new one every 3 years. For procedure, refer to 9-3. “Sampling
Unit Replacement”.
(8) Loop check and alarm test using TEST switch
Press the TEST switch with the test stick to send a pre-set analog output to the host system.
Check the output at the host system. Press the TEST switch to return the output to normal.
Refer to 7-4. “Operation - Test Mode”.

CAUTION

To maintain the reliability of the gas detector, perform a gas alarm test by using TEST
switch, etc. at least once a month.

While in test mode (alarm test using TEST switch), the gas alarm contacts activate. If
the gas alarm contacts are used to operate the interlocks of the external devices,
release the interlocks beforehand, as needed to prevent a possible activation of theinterlocks during the test mode, orenter the maintenance mode before entering the test mode, then release the interlocksof the external devices beforehand as needed. (Refer to 7-5. “Operation - Maintenance
Mode” for more information).
Notify those concerned before starting the gas alarm test.

Example of the check/inspection results
No.
1
2
3
4
5

Model
PS-7
PS-7

Base value
No.

LocationTarget gas
CO
SiH4

Alarm setvalue

Before
adj.

After
adj.

1st
stage

2nd
stag
e

1

Cabinet

0

0

50

100

2

Device A

0

0

5

10

3
4
5

Full scale value
250 ppm
25 ppm

Flow
rate

Alarm
test
using
TEST
switchAirtightness

Filterelement

Tubing

■
■
□
□
□

■
■
□
□
□

■
■
□
□
□

■
■
□
□
□

■
■
□
□
□

- 39 -

Replaceme
nt sensor
No.

Replacesampling
unit

H1021943―――

H1021944―――

9. Consumable Parts Replacement
This product has been designed so that its consumable parts can be easily replaced by the end
user. Contact New Cosmos or its authorized representative for ordering.

9-1. Filter Element Replacement
If the filter element (FE-1) is dirty, replace it with a new one by taking the following steps.
1. Loosen the nut of the filter unit (MF-50) and pull to separate the filter unit’s top from the inlet.
Tips when removing/reinstalling the entire filter
unit from/into the gas inlet:
Completely remove old sealing tape (noresidue). Wrap new sealing tape around thethreads of the filter unit (approx. 2.5 wraps).
Wrap sealing tape tautly to prevent slack.
Rotate andloosen the nut.
Inlet spacer
Nut

Tape size: 13mm (width) x 1005mm (length) x
0.1mm (thickness)
Tighten the filter unit so that movement of thespacer is not possible. Do not over tighten thefilter unit to prevent broken inlet.
Filter unit (MF-50)

2. Replace the filter element with a new one.
O-ringFilter element (FE-1)
Filter unit top
Nut
3. Install the filter unit top to the inlet. Rotate and tighten the nut to secure the tube. Ensure O-ringis correctly seated.

Rotate and tighten the nut.
O-ring must be present.

- 40 -

9-2. Sensor Unit Installation/Replacement

WARNING
Check that the target gas type and full scale value are correct before using a new sensor
unit. Also, check that the sensor unit expiration date has not been reached.
Note: The expiration year/month is not indicated on combustible gas sensor (CHS-7). CHS-7
is divided into two types, hot-wire combustible (CH) and catalytic (CS). The sensor life of CH
and CS types are 5 and 3 years from the installation date respectively.

CAUTION

Sensor unit replacement should be performed every 6 months. Replace the expired
sensor unit with a new one (except for combustible gas sensors (CHS-7)).

The expiration year/month is written on each sensor unit’s individual package. Replace
the old one with a new one before the expiration date.

Turn off the gas detector prior to sensor unit replacement. Setting the main unit powerswitch to the OFF position will turn off the trouble alarm output (open collector). If thetrouble alarm output is used to operate the interlocks of the external devices, release
the interlocks beforehand, as needed, to prevent a possible activation of the interlocks
during replacement.

1. Set the main unit power switch to the OFF position.
To OFF position

Lift the cover flap open.
Main unit power switch

2. Pull forward the latches on both sides of the base unit and lift the main unit to remove it fromthe base unit.
(2) Lift up the main unit.

(1) Pull forward the latches on both sides.

- 41 -

3. Press the top of the rear cover with thumb and tip the rear cover back to separate the rearcover from the main unit.
Press here then pull back the rear cover.

4. Insert a finger between the main unit and the sensor unit so that the sensor unit tilts forwardslightly. Hold the sensor unit by its sides, then pull it out of the main unit.
Insert a finger so that the sensor unit will tilt forward.

5. Insert a new sensor unit. Install the rear cover.

Push with palm to insert the sensor unit completely.

WARNING
If the sensor unit is not completely inserted, an airtight seal will not be created, and correctgas detection will not be possible.

- 42 -

6. Pull forward and hold the latches at both sides and connect the main unit by sliding it onto therails of the base unit.
(2) Align with the rail and slide on.

Rail(1) Pull forward and hold the latches at both sides.
7. Push the base unit’s latches back into place so that the white lines are visible, indicating thelatches have been locked.
Push the latch (lock position).

White line

Latch

WARNING Ensure that the latches are in the fully locked position (white lines visible). Normal
detection is not possible if latches are not fully locked.

NOTE

Dispose of used sensor/sampling units in accordance with applicable local laws
and regulations.

- 43 -

9-3. Sampling Unit Replacement

CAUTION

Turn off the gas detector prior to sampling unit replacement. Setting the main unit powerswitch to the OFF position will turn off the trouble alarm output (open collector). If thetrouble alarm output is used to operate the interlocks of the external devices, release
the interlocks beforehand, as needed, to prevent a possible activation of the interlocks
during replacement.

1. Remove the sensor unit by taking steps 1 to 4 of 9-2. “Sensor Unit Installation/Replacement”.
2. While pressing the front panel’s bottom with both thumbs, slowly press the panel forward to
remove it from the main unit.
Press with thumbs

Press here (2 places)

3. Disconnect the two connectors from the front panel.
Sampling unit

Front panel

Disconnect the connector from the pump unit.

Disconnect the connector from the front panel.

- 44 -

4. Connect the two connectors. Mate the sampling unit and front panel. Insert the sensor unit.
Install the rear cover.

Front panel
Rear cover

Ensure cables are not caught

WARNING
If the sensor unit is not completely inserted, an airtight seal will not be created, and correct gas
detection will not be possible. Take care that the cables should not be caught between the front
panel and sampling unit.

5. Install the main unit by referring to steps 6 and 7 of 9-2. “Sensor Unit installation/Replacement”.

NOTE

Dispose of used sensor/sampling units in accordance with applicable local laws andregulations.

- 45 -

10. Troubleshooting Before requesting repair, please refer to the table below. If the detector does not return tonormal operation after performing the corresponding steps in the table, or if your issue is notfound in the table, consult New Cosmos or its authorized representative.
 In the event of device failure, refer to 7-3. “Operation - Trouble Alarm”, too.
 For communication problems, refer to separate “PS-7-M communication specifications guide”.
Table 3. Troubleshooting
ProblemGreen POWER LED
does not turn on.

Amber TROUBLE
LED flashes.

Probable cause

Steps

Reference section

Base unit powerswitch is in OFF
position.

Set the switch to ON
position.

7-1.Operation
Procedure

Main unit powerswitch is in OFF
position.

Set the switch to ON
position.

7-1.Operation
Procedure

Incorrect wiring.

Check and rewire.
Securely connect
wires to terminals.

6-1.Wiring Procedure

Connector to the front
panel is loose.

Securely connect theconnector.

9-3. Sampling Unit
Replacement

Blown fuse.

Replace the fuse.
*Turn off the detector
before replacement.

5-3. Base Unit

Low flow rate due toclogged filter
element.

Replace the filter
element.

9-1. Filter Element
Replacement

Low flow rate due topump failure.

Replace the samplingunit.

9-3. Sampling Unit
Replacement

Low flow rate due toclogged tubing.

Remove clog fromtubing.

Connector to thepump unit is loose.

Securely connect theconnector.

9-3. Sampling Unit
Replacement

Incorrect sensor
installed (data does
not match the last
installed sensor type)Install the correct
sensor type.
To install a different
sensor type, press
COMM. button to
renew the data.

7-1.Operation
Procedure

Sensor unit failure

Replace the sensor
unit.

9-2. Sensor Unit
Installation/Replacem
ent

Sensor unit is absent.

9-2. Sensor Unit
Install the sensor unit. Installation/Replacem
ent

Flow sensor output isunstable immediately
after powering-up.

Leave the detector on
for about 30 minutes.

- 46 -

Problem

Probable cause

Gas concentration
value and ”_ _ _ _”flashing alternately.

Maintenance switch
is set to MNT1 or
MNT2.

No alarm contact
output.

Steps
Set the maintenanceswitch to the center
position (normal
operation mode).
Set the maintenanceswitch to the center
position (normal
operation mode).
Check and rewire.
Securely connect
wires to terminals.
Set the maintenanceswitch to the center
position (normal
operation mode).
1) Set the test mode
value to the one
greater than the zero
suppression set
value, or
2) Change the zero
suppression set
value.

Maintenance switch
is set to MNT1 or
MNT2.
Incorrect wiring.

Analog output is fixed
at 4mA or 17.4mA

Cannot change thetest mode value(fixed at 0).

Flow rate icon slowly
spins

Ethernet
communication error.

RS-485
communication error.

Status LED is on.
Status LED is off

Maintenance switch
is set to MNT2.

Test mode value isset within the zero
suppression range.

Reference section
7-5. Operation Maintenance Mode
7-5. Operation Maintenance Mode

6-1.Wiring Procedure

7-5. Operation Maintenance Mode
1) 7-4.Operation Test Mode
2) PS-7 gas
detector’s operation
manual for
administrators

Low flow rate due toclogged filter
element.

Replace the filter
element.

9-1. Filter Element
Replacement

Low flow rate due topump failure.

Replace the samplingunit.

9-3. Sampling Unit
Replacement

Low flow rate due toclogged tubing.

Remove clog fromtubing.

Poor LAN cableconnection.

Connect the LAN
cable.

6-1.Wiring Procedure

Incorrect IP address.

Check that the IP
address is correct.

5-4. DIP switches

Incorrectly set DIP
switch.

Set the mode change
5-4. DIP switches
switch to ETHERNET.

Incorrect unit ID.

Check that the unit ID
is correct.

Incorrectly set DIP
switch.

Set the mode change
5-4. DIP switches
switch to ETHERNET.

Communication error
between main unit
and base unit.
Loose connection of
main unit.

Remove and install
the main unit.

- 47 -

5-4. DIP switches

6-2. Unit Installation
Procedure11. Specifications
Detection principle
Sampling method
Sampling tube
Target gas
Detection range
Gas concentration
display
Alarm set value
Alarm accuracy

Alarm delay

Alarm indication

External outputs

Electrochemical (Catalyst conversion) with/without pyrolyzer,
Hot-wire semiconductor, Catalytic, or Galvanic cell
Extractive pump (500mL/min. auto-controlled)
PTFE, Outside and inside dia.: 6mm and 4mm (or 1/4 in. and 11/64 in.) *1
Piping length: < 20m *2
As per delivery specifications
As per delivery specifications
Four-digit LEDs on LCD display, with unit of measurement
20 segment bar graph
As per delivery specifications
 Combustible gas: 25% of alarm set value under identical conditions.
 Toxic gas: 30% of alarm set value under identical conditions.
 Low oxygen: 1vol% of alarm set value under identical conditions.
 Combustible gas: ≤ 30 seconds with a gas concentration that is 1.6 times
higher than the alarm set concentration.
 Toxic gas: ≤ 60 seconds with a gas concentration that is 1.6 times higher
than the alarm set concentration.
 Low oxygen: ≤ 5 seconds until the reading reaches 18vol% with a 10vol%concentration at 20C2C.
*Excludes delay time caused by piping length and communication time.
 Gas alarm (2 stages)
Red LED flashes.
ALARM1and/or ALARM2 shown on display.
 Filter element replacement notification
Flow rate icon slowly spins on display.
 Low flow rate alarm (with 10 second delay time)Amber LED flashes.
FLOW shown on display. Flow rate icon stops.
 Sensor fault/incorrect sensor installed
Amber LED flashes.
SENS. shown on display.
 Broken pyrolyzer wire
Amber LED flashes.
CONV. shown on display.
 Digital signal: Ethernet100base-Tx(Modbus/TCP) *3
Modbus/TCP (Max. number of connected units depends on the system
configuration.)Max. transmission distance: 100m up to HUB
Baud rate: 100Mbps
 Digital signal: RS-485 (Modbus/RTU) *3
Modbus-RTU (Max. number of connected units:32 units including master)
Method: 2-wire half duplex
Max. transmission distance: 1.2km up to the host device
Baud rate: 9600bps* Selectable to Ethernet or RS-485 using DIP switches.
 Gas concentration analog output signal
4-20mADC (common negative with power supply)
Output accuracy: ±0.5% of full scale* 0.6mA or less in the event of a trouble alarm* 300 Ω or less including wiring resistance- 48 -

Explosion-proof

 Gas alarm contacts (1st and 2nd stages)
N.O. dry contact (same common), self-resetting
Max. load: 30 VDC, 0.5A (resistive load) Trouble alarm open collector
N.C. self-resetting
Turns off (open position) in the event of low flow rate, sensor fault,
incorrect sensor installed, or broken pyrolyzer wire, no power, or blown
fuse.
Max. load: 30 VDC, 30mA (resistive load)
This product is not explosion-proof equipment.

Applicable cables for Terminal:
RJ-45 jack 8P8C
external terminals
Applicable cable: LAN cable, Cat. 5e or higher
Target signals: Digital signal, Ethernet100base-Tx and PoE

Applicable cable

Terminals:
Terminal blocks (7-pin x1 and 6-pin x1) Screw size: M3
Applicable cable: CVV-S cable 1.25mm² (2-core shielded twisted pair cable
is needed for RS-485.)
Target signals: Gas concentration analog output
Gas alarm contacts (1st and 2nd stages)
Trouble alarm open collector
RS-485 digital signal
Dia.8-11mm x 2 pcs

Operating conditions

Temperature: 0C to 40C (No sudden temperature change)
Humidity: 30 to 85%RH (No condensation)
Approvals
EMC:2014/30/EU／SI 2016 No.1091 *5
RoHS:2011/65/EU+(EU)2015/863／SI 2012 No.3032
Power supply
24 VDC 10% or Power over Internet (PoE) IEEE 802.3af/ANSI X3.263
Power consumption
Combination
CDS-7
CDS-7
COS-7
CHS-7
*4
+CDP-7
24 VDC, gasconcentration
analog output
used
24 VDC,
Ethernet, gasconcentration
analog output
not used
24 VDC RS-485(terminal) , gasconcentration
analog output
not used
PoE, Ethernet,
gas
concentration
analog output
not used

Dimensions
Mass
Mounting method

Typ.

Max.

Typ.

Max.

Typ.

Max.

Typ.

Max

2.3
W

4.7
W

2.8
W

4.7
W

3.0
W

5.7
W

4.8
W

8.0
W

2.4
W

4.1
W

2.9
W

4.1
W

3.0
W

5.0
W

4.9
W

7.3
W

2.7
W

4.6
W

3.2
W

4.6
W

3.4
W

5.5
W

5.2
W

7.8
W

2.8
W

4.4
W

3.5
W

4.4
W

3.7
W

5.4
W

5.7
W

8.3
W

W62mm×H142mm×D157mm ( excluding protrusions, without pyrolyzer )W62mm×H172mm×D157mm (excluding protrusions, with pyrolyzer)
Approx.1.2kg (without pyrolyzer )Approx.1.3kg (with pyrolyzer)
Wall mounting*1. Teflon recommended. For adsorbable gas, consult New Cosmos or its authorized representative for the- 49 -

recommended material. Specify 1/4 in. 11/64 in. outside and inside diameter during order placement if thestandard 6mm and 4mm outside and inside diameter tubing will not be used.
*2. For adsorbable gas (e.g. HF, F2, HCl, Cl2, NH3), use of less than 5m length piping is recommended.
When using this product in a place exposed to dust, the piping may need to be shorter than recommended
and periodiAbocally replaced.
*3. Refer to” PS-7-M communication specifications guide” (separate document) for the PS-7-M functioncommand table and Modbus register map.
*4. More power is consumed when both analog output and digita signals are used.
* The above specifications are subject to change without notice.
* If your specifications are nonstandard, refer to the delivery specifications.
*5. RS-485 communication function is outside the scope of the CE marking.

12. Warranty
The warranty period is one (1) year from the date of purchase.
You are entitled to the limited warranty, if the product malfunctions due to a manufacturing defectduring normal use in accordance with the instruction manual, specifications and labels.
1. Warranty Scope
If the product fails or is found to be damaged due to a manufacturing defect during the warranty
period, and used in accordance with the instruction manual and specifications, we will provide afree replacement and repair service. This warranty covers the New Cosmos product/parts only
and not third party product/parts.
2. Warranty Exclusions
The following will be repaired at the cost of customer even during the warranty period.
(1) Failures and damages incurred by incorrect use, deliberate acts or negligence of the user.
(2) Failures and damages caused by disaster, earthquake, storm and flood, lightning, extreme
climate, abnormal power supply voltage, excessive electromagnetic interferences, or otheracts of God.
(3) Failures and damages resulting from repair and/or modification by non-New Cosmos certified
technicians.
(4) Consumables and failures and damages resulting from improper consumable replacement.
(5) Other failures and damages not attributable to the manufacturer.

13. Service Life of Detector
The service life of this product is 10 years. The unit can operate for up to 10 years with a standard
installation and used in accordance with the instruction manual. When the service life has expired,replacement is needed for continued reliable performance.

14. Disposal of Detector/Sensor/Sampling
Dispose of used sensor units/sampling units/gas detectors in accordance with applicable local
laws and regulations.

- 50 -

15. Detection Principle
15-1. Electrochemical (Catalyst conversion) Sensor (CDS-7)
This sensor consists of three electrodes and an electrolyte, and the method adopted here is to
produce electrolytic oxidation with a potentiostat circuit while keeping the working electrode at aconstant potential against the reference electrode. Measuring the current generated here allows
determining the concentration of the gas (e.g. H2S, CO).
The electrolytic reaction of H2S is as follows:
Working electrode:H2S + 4H2O  H2SO4 +8H+ + 8e
Counter electrode: 2O2 + 8H+ + 8e  4H2O

15-2. Hot-wire Semiconductor Sensor (CHS-7-CH)
A small amount of metal oxide semiconductor is deposited on a platinum coil, then the platinum
coil is heated to a high temperature. When combustible gases react with oxygen absorbed on thesurface of the semiconductor, free electrons increase in the semiconductor. As a result, theresistance of the semiconductor decreases. This resistance change is read as differential voltage
using a bridge circuit for gas detection purpose. This type of sensor is very sensitive and thus
suitable for low concentration gas detection.

15-3. Catalytic Sensor (CHS-7-CS)
Catalytic combustion occurs on the catalytic layer applied on a platinum coil even if the gas
concentration is well below the lower flammable limit (LFL). This causes a rise in temperatureof the platinum coil and increases its electrical resistance. This change is read as a differential
voltage using a bridge circuit. This process enables detection of combustible gases in air up to
the lower explosive limit (LFL).

15-4. Galvanic Cell Sensor for Oxygen detection (COS-7)
The sensor consists of two electrodes, a membrane and an electrolyte.
The electrodes are two different metals, noble metal (Pt, Ag) and base metal (Pb). The noble
metal electrode has contact with air via a Teflon membrane. Connecting load resistance to bothelectrodes generates a potential difference, which promotes the following reactions:
Noble metal electrode:O2 + 2H2O + 4e  4OHBase metal electrode:2Pb  2Pb2+ + 4e

As a result, the current proportional to the oxygen concentration in the air flows from the noble
metal electrode to the base metal electrode via the external circuit. Since the electromotive forcechanges depending on the temperature, a thermistor is added to compensate for the ambient
temperature variations.

- 51 -

16. GlossaryTerm
Gas detector

Flameproof enclosure(explosion-proof
enclosure)
Target gas

Definition
Device used to detect the presence of a target gas and to give its
concentration in the form of an electrical signal.
Enclosure in which the parts which can ignite an explosive
atmosphere are placed. This enclosure can withstand the pressure
created during an internal explosion of an explosive mixture, andprevent the ignition of an explosive atmosphere outside theenclosure.
Specific gas to be detected, concentration displayed, and used totrigger alarms.

Alarm set value

A gas concentration value that is set on a gas detector for alarm
activation.

Detection range

A range of target gas concentrations that can be displayed and trigger
alarms.

Maintenance andinspection

Tasks performed to ensure that equipment operates normally andcorrectly.
The length of time a gas detector takes to activate an alarm after it is
exposed to a target gas concentration higher than the alarm set value
or to some other specified conditions.
Gas specifically prepared to calibrate/adjust the gas detection andalarm system.

Alarm delay
Calibration gas( test gas)
Hazardous area

An area in which an explosive atmosphere is present, or may be
expected to be present, in quantities such as to require special
precautions for the construction, installation and use of electricalapparatus.

Non-hazardous area

An area in which an explosive atmosphere is not expected to bepresent in quantities such as to require special precautions for theconstruction, installation and use of electrical apparatus.

Explosive atmosphere

Mixture of air and flammable substances in the form of dust or vapor
which are within their explosive limits.

LEL (or LFL)

Lower Explosive Limit (or Lower Flammable Level). Lowest
concentration (percentage) of a gas or vapor in air capable ofproducing a flash fire, or explosion in the presence of an ignition
source like arc, flame or heat.

%LEL

Concentrations of combustible gas given in terms of percent of thelower explosion limit.

vol%Gas concentrations given in terms of percent of cubic volume.

ppm

Gas concentrations given in terms of millionth part of cubic volume.

- 52 -

Revision History
Document No.

Date

Revision

GAE-138-00
GAE-138-01

Feb 2019
Oct 2021(Initial issue)
01

GAE-138-02

September 2022

02

Additional copies of this instruction manual may be purchased.
Contact New Cosmos or its authorized representative for ordering.

Authorized representative:

Manufacturer:
NEW COSMOS ELECTRIC CO., LTD.
2-5-4 Mitsuya-naka, Yodogawa-ku
Osaka 532-0036, Japan
URL: http://www.new-cosmos.co.jp