PT2E-18813

Indoor Oxygen Monitor

OX-600Operating ManualContents
1 Outline of the Product...................................................................................................................................... 3
Preface ............................................................................................................................................................ 3
Purpose of use ................................................................................................................................................ 3
Definition of DANGER, WARNING, CAUTION and NOTE ............................................................................ 4
Method of confirmation for CE/UKCA marking type ....................................................................................... 4
2 Important Notice on Safety .............................................................................................................................. 5
2-1. Danger cases........................................................................................................................................... 5
2-2. Warning cases ......................................................................................................................................... 6
2-3. Precautions .............................................................................................................................................. 6
3 Product Components ....................................................................................................................................... 7
3-1. Main unit and standard accessories ........................................................................................................ 7
3-2. Names and functions for each part ......................................................................................................... 9
4 How to Install ................................................................................................................................................. 124-1. Precautions for installation points ......................................................................................................... 12
4-2. Precautions for system designing ......................................................................................................... 14
4-3. Installation of main unit .......................................................................................................................... 16
4-4. Precautions for wiring ............................................................................................................................ 21
5 How to Use .................................................................................................................................................... 25
5-1. Before using the monitor ....................................................................................................................... 25
5-2. Preparation for start-up ......................................................................................................................... 25
5-3. Power-on ............................................................................................................................................... 25
5-4. User mode ............................................................................................................................................. 27
5-5. Air calibration ......................................................................................................................................... 29
5-6. Setting value check ............................................................................................................................... 30
5-7. Power-off ............................................................................................................................................... 32
6 Alarm Activation and Functions ..................................................................................................................... 33
6-1. Gas alarm activation .............................................................................................................................. 33
6-2. Fault alarm activation ............................................................................................................................ 38
6-3. External output operation ...................................................................................................................... 39
6-4. Suppression function ............................................................................................................................. 40
6-5. Correction processing function .............................................................................................................. 41
6-6. Auto air calibration function ................................................................................................................... 41
7 Maintenance .................................................................................................................................................. 42
7-1. Maintenance intervals and items ........................................................................................................... 42
7-2. Maintenance (regular maintenance) mode ........................................................................................... 44
7-3. Preparation for zero and span adjustment ............................................................................................ 49
7-4. Zero adjustment ..................................................................................................................................... 50
7-5. Span adjustment .................................................................................................................................... 51
7-6. Environmental setting ............................................................................................................................ 52
7-7. Return to user mode .............................................................................................................................. 58
7-8. Consumables ......................................................................................................................................... 58
8 Storage and Disposal .................................................................................................................................... 59
8-1. Procedures to store the monitor or leave it for a long time ................................................................... 59
8-2. Procedures to relocate the monitor or use it again ............................................................................... 59
8-3. Disposal of products .............................................................................................................................. 60
9 Troubleshooting ............................................................................................................................................. 61
10 Product Specifications ................................................................................................................................. 63
10-1. List of specifications ............................................................................................................................ 63
10-2. List of accessories ............................................................................................................................... 64
11 Appendix ...................................................................................................................................................... 65
11-1. Detection principle of galvanic cell type .............................................................................................. 65
11-2. Definition of terms ................................................................................................................................ 66-2-

1 Outline of the ProductPreface11Outline of the ProductPrefaceThank you for choosing our indoor oxygen monitor OX-600 (hereinafter referred to as the monitor).
Please check that the model number of the product you purchased is included in the specifications on
this manual.
This manual describes how to use the monitor properly and its specifications. Not only the first-timeusers but also the users who have already used the monitor must read and understand the operating
manual and use this product as described in this manual.
Note that the contents of this manual are subject to change without notice for product improvement. It
is also prohibited to copy or reproduce this manual, in whole or in part, without permission.
Regardless of warranty period, we shall not make any indemnification for accidents and damage
caused by using the monitor.
Make sure to read the warranty policy specified on the warranty.

Purpose of use
This indoor oxygen monitor measures oxygen in the air and issues an alarm using the buzzer and
LCD backlight when oxygen concentration drops below preset concentration (alarm setpoint). Whiledisplaying measured oxygen concentration on the LCD, the monitor converts it to an analog signal of
4 - 20 mA or 0 - 1 V to output (only 0 - 1 V for the dry battery type) and outputs a two-step gas alarm
contact at a gas alarm state.
The monitor is a safety unit, not an analyzer which performs quantitative/qualitative
analysis/measurement for oxygen. Check the specifications before use and conduct measurement
properly in accordance with purposes.

-3-1 Outline of the ProductDefinition of DANGER, WARNING, CAUTION and NOTE

Definition of DANGER, WARNING, CAUTION and NOTE
Throughout this manual, the following indications are used to ensure safe and effective work.
DANGER

This message indicates that improper handling may cause serious damageon life, health or assets.

WARNING

This message indicates that improper handling may cause serious damage
on health or assets.

CAUTION

This message indicates that improper handling may cause minor damage
on health or assets.

NOTE

This message indicates advice on handling.

Method of confirmation for CE/UKCA marking type
The CE/UKCA marking is labeled on the detector in case of comply with CE/UKCA marking. Please confirm
the instrument specification before using. Please refer Declaration of Conformity that is at the end of thismanual if you have CE/UKCA marking type.
You can confirm instrument specification to see the CE/UKCA marking as follows.

CE/UKCA marking

CE/UKCA marking label (Bottom of instrument)(DC specification, dry battery type only)-4-

2 Important Notice on Safety

2-1. Danger cases

22Important Notice on Safety
To maintain the performance of the monitor and use it safely, observe the following instructions withWARNING and CAUTION.

WARNING If an abnormality is found in the monitor, contact RIKEN KEIKI immediately. Visit our Web site tofind your nearest RIKEN KEIKI office.
Web site: https://www.rikenkeiki.co.jp/

2-1. Danger cases
DANGER
 This is not an explosion-proof unit. Never attempt to measure a gas in an atmosphere over the
lower explosive limit.

-5-2 Important Notice on Safety

2-2. Warning cases

2-2. Warning cases
WARNING Before turning on the monitor, always check that the voltage is compliant with the specifications.
Operating on an unstable power supply may cause malfunctions.
 When air calibration is performed, check the atmosphere for freshness before beginning it. If
interference gases exist, the air calibration cannot be performed properly, thus leading to dangers
when an oxygen deficiency occurs.
 Do not operate this monitor in a place where combustible/explosive gases or vapors are present.
Operating the monitor in such an environment will lead to extreme dangers.
 Issuance of an oxygen deficiency alarm indicates that there are extreme dangers. Take proper
actions based on your judgment.
 Perform span adjustment at fixed intervals.
 Make sure that the monitor is installed in a place where it is in contact with the atmosphere. If themonitor is installed in a place where it is in less contact with the atmosphere, it may not detect thecorrect oxygen concentration, thus leading to an oxygen deficiency accident.
 Do not run the power cable and remote sensor cable of the monitor in parallel with cables ofhigh-frequency or high-voltage and other device's power cables.
 If a cable of high-frequency or high-voltage and the power cable need to intersect with each other,it should be orthogonally connected.
 When wiring, be careful not to apply any stresses on the cables by pulling, tightening or twisting.
 Do not disassemble/modify the monitor. It may invalidate the warranty of the performance.
Changing the settings without understanding them may cause alarm malfunctions. Please use themonitor properly in accordance with the operating manual.

2-3. Precautions
CAUTION Do not use a device, such as a transceiver, which transmits a radio wave near the monitor or its
cables. It may affect the measurement. If a transceiver or other radio wave transmitting device isused, it must be used in a place away from the monitor where it disturbs nothing.
 Restarting the monitor within five seconds after turning it off may cause errors.
 This is not a control unit. It is not allowed to use the external output of the monitor to control otherunits.
 This is a safety unit. Never fail to perform a regular maintenance to ensure safety. Continuing to
use the monitor without performing maintenance will compromise the sensitivity of the sensor,
thus resulting in inaccurate gas detection.
 Do not pick the sensor or buzzer opening with a sharp-pointed item. The unit may cause
malfunction or get damaged, possibly resulting in incorrect measurements.
 Do not let the monitor draw in water. Do not also install the monitor in a place where the monitor
may get wet. Ignoring this may cause malfunction because the monitor is not water- anddrip-proof.
 This is a precision device. Do not give strong shock or vibration to the monitor.
 When the case is opened for wiring or other operation, do not touch inner parts. When wiring, besure that excessive pressure is not applied to the power cable and remote sensor cable.
 Do not block the vent for the sensor.

-6-

3 Product Components

3-1. Main unit and standard accessories

3
3

Product Components

3-1. Main unit and standard accessories
After opening the carton box, check the monitor and accessories.
If there is anything missing, contact RIKEN KEIKI.

Main unit
For names and functions of individual parts of the monitor and LCD display, see "3-2. Names and functions
for each part" (P.9).
OX-600 main unit

Sensor unit (Remote type)NOTE

 Which type to use - sensor integrated type or sensor unit supplied type (remote type) - can be orderedat the time of purchase.
 The sensor integrated type does not include the sensor unit (remote type).
 The cable length for the remote type can be selected from 3, 5, 10 and 20 m.

-7-

3 Product Components

3-1. Main unit and standard accessories

Standard accessories• Cross-recessed pan headmachine screw (2 pcs.)• Cross-recessed round head woodscrew (2 pcs.)• 3.2 m AC power cable (1 pc.) *Supplied only with AC specification• Operating manual (1 pc.)

CAUTION The main unit and sensor unit (remote type) are precision devices. Be careful not to drop themonitor when installing or uninstalling the main unit or sensor unit. Dropping the monitor may
compromise its original performance or cause malfunctions.

Optional accessories• Installation board (1 pc.)
• Gas calibration cap (1 pc.)

Outline drawing
Cable outlet
Power switch
Display

Cable outlet

Cable outlet

Cable outlet

Sensor part

Main unit
Mounting hole for
3-M3
Use one of the twofor lower holes

To main unit

To main unit

Remote sensor-8-

To main unit

3 Product Components

3-2. Names and functions for each part3-2. Names and functions for each part
This section describes the names and functions of the individual parts and LCD display that make up themonitor.

Main unit

Name

Major function
Turns the power ON/OFF. Slide the switch up to power on and down
to power off.
Hold down this button to enter the user mode.
It is also used to cancel or skip during setup.

(1)

Power switch(2)

MODE button(3)

˄ button

Used to change the screen and increase numerical values during
setup.

(4)

˅ button

Used to change the screen and decrease numerical values during
setup.

(5)

SET button

Used to confirm the setting.

(6)
(7)

Buzzer sound opening
Sensor part

Emits operation and judgment sounds. (Do not block it.)
Detects a gas to be detected. The sensor is inside the cover.

(8)

Screw

Loosen this screw to open the case.

-9-3 Product Components

3-2. Names and functions for each part

Display(1)

NameOperating state display

Major function
Displays the operating status. Blinks at a normal state.

(2)

1st alarm display

Lights up or flash in orange at a first alarm state.

(3)

2nd alarm display

Lights up or flash in red at a second alarm state.

(4)

Fault alarm display

Lights up in red at a fault alarm state.

(5)Concentration value
display
Maintenance indicator

Displays the gas concentration.
Maintenance items and others are displayed during setup.

Unit display
Gas name display
Maintenance display

Displays the unit (%) according to the specification.
Displays the gas name (O2: Oxygen).
Maintenance items and others are displayed during setup.

(8)

AC/DC power display

Lights up when the monitor is operating on AC or DC power.

(9)

Battery level icon

Displays the battery level when the monitor is operating on dry
batteries.

(10)

This is not used for the monitor.

(6)
(7)

Installation of batteries (for dry battery type)
When the monitor is used for the first time, or when the battery level is low, install or replace with the new
AA alkaline dry batteries according to the following procedure.

CAUTION Turn off the power of the monitor before replacing the batteries.
 Replace the batteries in a safe place where explosive gases are not present.
 Never fail to use alkaline batteries. If a rechargeable (secondary battery) nickel-cadmium battery
or nickel metal hydride battery is used, the specifications cannot be met, such as continuous
operating time.
 Replace all of the two batteries with new ones at one time.
 Pay attention to the polarities of the batteries when installing them.
 Completely lock the battery cover after installing the batteries. If the battery cover is notcompletely locked, the dry batteries may drop off.
 Do not use rechargeable batteries that may interrupt a measurement due to the discharge
characteristic of rechargeable batteries.

- 10 -

3 Product Components

13-2. Names and functions for each part

Check that the power of themain unit is turned off.
If the power is turned on, slide thepower switch down to turn it off.

2

Remove the battery case fromthe monitor.

Unlock the tab of the battery case.

3

Put new batteries (two AA
alkaline dry batteries) in thebattery case.

New battery

Confirm that the polarities of thebatteries are correct.

4

Put the battery case back in themonitor.

Push the circled area andconfirm that the tab is locked.

- 11 -

4 How to Install

4-1. Precautions for installation points

44

How to Install

4-1. Precautions for installation points
When installing the monitor, never fail to observe the following precautions.
Ignoring the precautions may damage the monitor, resulting in inaccurate gas detection.

CAUTION This is a precision device. Because the monitor may not provide the specified performance insome places (environments), check the environment in the installation site, and then takeappropriate actions if necessary. Because the monitor plays an important role for safety anddisaster prevention, it must be installed in appropriate points.
 Do not install this product in any of the following locations.
 Place exposed to direct sunlight or outside
 Place exposed to water Place exposed to ventilation from an air conditioner, etc.
 Place exposed to soot, smoke or steam Place where the temperature drops below -10ºC or rises over 40ºC or the temperature changes
suddenly Place with high humidity like a bathroom
 Place with bad ventilation such as behind a curtain or under the shadow.

<Do not install the monitor in a place with vibrations or shocks.>
The monitor consists of sensitive electronic parts. The monitor must be installed ina stable place without vibrations or shocks, etc. and it cannot drop.

<Do not install the monitor in a place exposed to water, oil orchemicals, etc.>
When selecting installation points, avoid a place where the monitor is exposed toliquids such as water, oil, or chemicals.

<Do not install the monitor in a place where the temperaturedrops below -10ºC or rises over 40ºC.>
The operating temperature of the monitor is -10 to +40ºC. Install the monitor in astable place not exceeding the operating temperature range.

<Do not install the monitor in a place exposed to direct sunlightor sudden changes in the temperature.>
Avoid a place where the monitor is exposed to direct sunlight or radiant heat
(infrared rays emitted from a high-temperature object), and where the unit
temperature changes suddenly. Condensation may be formed inside the monitor,or the monitor cannot adjust to sudden changes in the temperature.
- 12 -

4 How to Install

4-1. Precautions for installation points<Keep the monitor (and its cables) away from noise source
devices.>
When selecting installation points, avoid a place where
high-frequency/high-voltage devices exist.

<Do not install the monitor in a place where maintenance of the monitor cannot
be performed or where handling the monitor involves dangers.>
Regular maintenance of the monitor must be performed.
Do not install the monitor in a place where the machinery must be stopped when maintenance isperformed in its inside, where parts of the machinery must be removed to perform maintenance, orwhere the monitor cannot be removed because racks or other things prevent access to it. Do not install
the monitor in a place where maintenance involves dangers, for example, near a high-voltage cable.

<Do not install in places where the atmosphere is normally oxygen deficient.>
Do not install the monitor or remote sensor in places where the atmosphere is normally oxygen-deficient(less than 18vol%).
In particular, readings may be incorrect if the sensor is frequently exposed to atmospheres in which theconcentration of oxygen is 1vol% or less.

<Do not install the gas detector facing up.>
Install the monitor so that the front face (display panel) faces downward or sideways. Gas may not be
detected correctly if the monitor is installed facing up.

Ceiling

Wall

NG

OK
OK

- 13 -Floor

4 How to Install

4-2. Precautions for system designing

4-2. Precautions for system designing
Note the following precautions for system designing of the monitor.

CAUTION An unstable power supply and noise may cause malfunctions or false alarms.

Using a stable power supply
The external output and alarm contact of the monitor may be activated when the power is turned on, whenmomentary blackout occurs, or when the system is being stabilized. In such cases, use a UPS(uninterruptible power system), or take appropriate actions on the receiving side.
The monitor must be provided with the following power supply.
Power supply
voltageAllowed time of
momentary
blackout

Others100 - 120 VAC ±10% (50/60 Hz), 24 VDC±10% or AA alkaline dry battery (2 pcs.)
Up to 10 milliseconds(To recover from the momentary blackout for 10 milliseconds or more, restart themonitor.)
Example of actions
To ensure continuous operation and activation, install a UPS (uninterruptible powersystem), etc. outside the monitor.
Do not use it with a power supply of large power load or high-frequency noise.
Example of actions
Use a line filter, etc. to avoid the noise source if necessary.

- 14 -

4 How to Install

4-2. Precautions for system designing

Proper use of alarm contact
The alarm contact of the monitor is used to transmit signals to activate an external buzzer, alarm lamp or
rotating lamp. Do not use it for controlling purpose (e.g., controlling the shutdown valve).
In case of the dry battery type, can not use the alarm contact.

CAUTION The b contact (break contact) under de-energized state may be opened momentarily by a physicalshock, such as external force.
When the b contact is selected for the alarm contact, take appropriate actions to prepare for a
momentary activation, for example, add signal delay operation (approximately one second) to thereceiving side of the b contact.

The specifications for the external output gas alarm contact of the monitor are based on the resistance loadconditions. If inductive load is used at the alarm contact, the following errors will occur easily because
counter electromotive force is generated at the contact.
• Deposition, defective insulation or defective contact at the relay contact• Damage of any electric parts due to high-voltage generated inside the monitor• Abnormal operations by an out-of-control CPU
If load is to be activated, appropriate measures must be taken to stabilize the operation of the monitor andprotect the alarm contact referring to the following information.
• Relay it with an external relay at a lower voltage of 120 VAC or below (contact amplification). At the sametime, the surge absorbing part SK1 suitable for the specifications must be attached to the external relay.
• In addition, the surge absorbing part SK2 must be attached to the loaded side of the external relay ifnecessary.
• It may be recommended that the surge absorbing part should be attached to the contact for certain loadconditions. It must be attached to an appropriate position by checking how the load is activated.

Load

Coil

Alarm contact

PowersupplyPowersupplyExternal relay(Lower voltage relay)*SK1, SK2: Surge absorbing part

CAUTION In principle, do not activate inductive load at the alarm contact of the monitor. In particular, never
use the inductive load to activate a fluorescent lamp or motor.
 If inductive load is activated, relay it with an external relay (contact amplification). However,
because the coil of an external relay also involves inductive load, select a relay at a lower voltage(120 VAC or below), and then protect the contact of the monitor with an appropriate surge
absorbing part, such as a CR circuit.

- 15 -

4 How to Install

4-3. Installation of main unit

4-3. Installation of main unit
Install the main unit on the wall 50 to 180 cm up from the floor.
If wall screws are available, remove the screw at the lower part of the main unit to open the cover andinstall the unit using the mounting holes on the back of the unit.

CAUTION Install the sensor in a place not directly exposed to ventilation from an air conditioner.
Sudden changes in the temperature may cause the readings not to come back.

Mounting hole (for M4
screw)*Supporting the switch box

NOTE To install the main unit to the wall with screws, use the mounting holes on the back of the unit
according to the following procedure.
(1) Loosen the screw at the lower part of the main unit and open the surface cover of the case.
(2) Fix the main unit with two screws (M4) through the mounting holes.
(3) Put the surface cover back on the case and tighten the screw at the lower part of the main unit.

- 16 -

4 How to Install

4-3. Installation of main unit

If the monitor operating on dry batteries needs to be removed with the power on, use the installation board(option). When the installation board is used, fix the board before installing the main unit.

Mounting hole(for M4 screw)<Installation of Remote Sensor>
Tighten the screws through one upper mounting hole and one of the two lower mounting holes.
Mounting hole for 3-M3
Use one of the two for lower holes

To main unit

NOTE

 To install the remote sensor to the wall using screws, use the mounting holes on the back of thesensor according to the following procedure.
(1) Open the surface cover of the remote sensor.
(2) Fix the sensor with two screws (M3) through the mounting holes (one upper mounting hole andone of the two lower mounting holes).
(3) Put the cover back on the remote sensor.

- 17 -

4 How to Install

4-3. Installation of main unit

<Maintenance Space>
For the dry battery type, secure a maintenance space for battery replacement below the unit. If theinstallation board (option) is used, secure an installation space above the unit so that it can be installed bysliding.

Secure as
installation space

Secure as battery replacement space

Secure as battery replacement space(Only for dry battery type)(Only for dry battery type)Installation dimension drawing (Installation board used)

Installation dimension drawing (Installation board not used)
Compatible with JIS single switch box- 18 -

4 How to Install

4-3. Installation of main unit

Preparation of sensor
1

Remove the sensor cover of thesensor part.

Sensor coverInsert a coin straight to the recessedarea at the lower right of the monitor
to move up the sensor cover.

Remove the sensor cover to checkthe sensor.

2

Insert the sensor pin to thesocket on the board.
Because the sensor has two pins,align them with the open holes on theboard when inserting or removing.

3

Put the sensor cover back on.

- 19 -

4 How to Install

4-3. Installation of main unit

CAUTION When installing the sensor, push it while aligning its pins with the socket on the board. Ignoring
this may bend and damage the sensor pins.
 After the sensor is installed, always perform a calibration (zero adjustment and span adjustment).
 Do not disassemble the sensor because it contains electrolyte. If contact occurs, rinse the area
immediately with a large quantity of water.
 The sensor must be stored under normal temperature/humidity in a clean place away from direct
sunlight.

<Preparation of Sensor Unit>
1

Remove the sensor cover of thesensor unit.
Push the tabs on the both sides withyour fingers to move up the sensor
cover.
Remove the sensor cover to checkthe sensor.

2

Insert the sensor pin to thesocket on the board.
Because the sensor has two pins,align them with the open holes on theboard when inserting or removing.

3

Put the sensor cover back on.

- 20 -

4 How to Install

4-4. Precautions for wiring

4-4. Precautions for wiring
If the monitor operates on AC or DC power, or inductive load is used at the alarm contact, wiring work is
required.
The following cables are recommended for wiring the monitor with the power supply, signal cable andcontact.
<Recommended Cables>
For AC power
For DC power
For signal cable(4 - 20 mA/0 - 1 V)
For contact

Solid wire/stranded wire: 0.2 - 1.5 mm2
CVVS: 0.2 - 1.5 mm2
CVVS: 0.2 - 1.5 mm2
Cable such as CVV (0.2 - 1.5 mm2) Up to 4 cores

CAUTION Be careful not to damage the internal electronic circuit when wiring. In addition, be careful not toapply stresses on the monitor when (overweight) cables are installed.
 The power and signal cables must be wired separately from the motor power cables.
 When stranded wires are used, prevent wires from contacting each other.

<Cable Connection Conditions>
Connectable cable, bare wire length and connection tools are as follows:• Cable: 0.2 - 1.5 mm2• Bare wire length: 10 - 11 mm• Connecting tools: Dedicated screwdrivers manufactured by WAGO and equivalent (edge width 3.0 to 4.5mm x 0.5 mm)

CAUTION
The specified bare wire length must be observed when the wire insulation is peeled off.
 Improper clamping of the wire due to a shorter bare wire length may cause defective electric
conduction or heating.
 Catching the wire insulation due to a shorter bare wire length may cause defective electric
conduction or heating.
 Exposing the wire due to a longer bare wire length may cause defective insulation or a shortcircuit.
 Be careful not to break up the wire. If the wire is broken up when inserted to the terminal, this may
cause defective insulation or heating.

<Compatible Bar Terminal>
For a bar terminal, the following items are available.
• Bar terminal (ferrule): Model 216 Series (manufactured by WAGO)• Crimping tool: Model VarioCrimp 4 (206-204) (manufactured by WAGO)

CAUTION A bar terminal of the specified model must be used. Using other bar terminals invalidates thewarranty of the performance.

- 21 -

4 How to Install

4-4. Precautions for wiring

How to connect to terminal plate
When cables (wires) are connected to the terminal plate inside the main unit, use the dedicatedscrewdriver or a compatible flathead screwdriver.
When connecting a stranded wire, be sure to press the push button and open the spring while connecting
the wire.

1

Push the push button straight
downward using thecompatible screwdriver or
equivalent to open the spring.

2

Insert a wire with a specified
bare wire length (10 mm) until
the end of it reaches thedeepest point.

3

Release the screwdriver.
The wire is connected.

CAUTION Never fail to use the correct tool.
 Do not insert more than one wire into one wiring hole. If the total size (mm2) of two or more wires iswithin the maximum wire connection range of the terminal plate, it may cause reduced springclamping force, defective insulation due to clogged wire sheath, defective contact or coming off ofwires.

- 22 -

4 How to Install

4-4. Precautions for wiring

NOTE<Compatible Screwdriver> When opening the spring, use the compatible screwdriver manufactured by WAGO or equivalent (ascrewdriver with an edge width of 3.0 to 4.5 mm x 0.5 mm which can fully open the spring: See thetable below). In doing this work, be careful not to apply excessive force. Ignoring this may damage thehousing/push buttons or cause dropping off of the push buttons.
Compatible screwdriver manufactured by WAGO
Screwdriver (M) straight type
Screwdriver (M) straight type (short shaft & grip)
Screwdriver (M) straight type (insulated shaft type)- 23 -

210-120J
210-350/01
210-657
210-720

4 How to Install

4-4. Precautions for wiring

Figure of terminal plate
The overview of the terminal plate inside the main unit is as follows:
For external output signal (4 - 20 mA/0 - 1 V) (TN2)
1: (+)
2: (-)For contact (TN3)
1 - 2: ALM1 (First)
3 - 4: ALM2 (Second)<For Connecting AC Power>
AC power (TND)
100 - 120 VAC ± 10% (50 Hz/60 Hz)
1: L
2: N
3: Not used

Terminal board for AC power<For Connecting DC Power>
DC power (TND)
24 VDC ± 10%
1: (+)
2: (-)
3: N.C

Terminal board for DC power- 24 -

5 How to Use

5-1. Before using the monitor

55

How to Use

5-1. Before using the monitor
Not only the first-time users but also the users who have already used the monitor must follow theoperating precautions.
Ignoring the precautions may damage the monitor, resulting in inaccurate gas detection.

CAUTION After you received the monitor, start using the monitor within the specified operation start limit of its
sensor.

5-2. Preparation for start-up
Check the following points before starting oxygen concentration monitoring.
- Before turning on the power, check that the monitor is installed properly and the external wiring is done
properly.
- Check that the power supply voltage is compliant with the specifications.
- Because the external contact may be activated during the adjustment, take measures to prevent anactivated contact from having influences on external circuits.

5-3. Power-on
1Turn on the power switch.
Powerswitch- 25 -

5 How to Use

5-3. Power-on

All items are displayed.

About 25-second initial clear (system
check of the monitor and alarmdeactivation) runs.

The monitor is in the measurement
state.

CAUTION Do not turn off the monitor during the initial clear. When turning it on again, abnormal operation
may occur.
 After initial clear, perform air calibration.
 The monitor must be warmed up for approximately one hour. Air calibration must be performed
after warmed up.

NOTE External output during initial clear is as follows:• 4 - 20 mA: About 17.4 mA fixed• 0 - 1 V: About 0.84 V fixed To turn off the power, slide the power switch down.

- 26 -

5 How to Use

5-4. User mode

5-4. User mode
The user mode allows for performing air calibration and checking setting values.

1

Keep the MODE button pressed(for three seconds) in themeasuring state.
The user mode is displayed.

2

In the user mode, press the ˅or ˄ button.
The display items are switched.

3

After operation, hold down the
MODE button.
The monitor returns to the measuring
state.

WARNING After air calibration, hold down the MODE button to return to the measuring state.
The monitor automatically returns to the measuring state in 10 hours.

- 27 -

5 How to Use

5-4. User mode

Items that can be checked and set in user mode
Item

Details

LCD display

Remarks

Program version

Show the current
program version.

Air calibration

Perform the air
calibration.

Press the SET
button to go to
the air
calibration
screen.
(P. 29)Setting value check

Check settings suchas alarm setpoint,
zero suppression
value, and airpressure correction.

Press the SET
button to go to
the setting
confirmation
screen.
(P. 30)

Maintenance modeswitching

Switch to themaintenance mode.

- 28 -

5 How to Use

5-5. Air calibration

5-5. Air calibration
Air calibration is zero adjustment to correctly measure the current gas concentration.

1

In the user mode, press the ˄
button once.

2

Press the SET button.

3

Press the SET button again.
The concentration display
blinks.

4

Press the ˅ or ˄ button toadjust the concentration value
to "20.9%".

5

Press the SET button.
Air calibration is performed.
After air calibration iscompleted, "PASS" isdisplayed and the monitor
returns to the display in step 2.

Press the SET button to display thecurrent concentration.

*

6

If air calibration fails, "FAIL"
is displayed.

After checking the setting
value, hold down the MODE
button.
The monitor returns to the measuring
state.

CAUTION When turning on the power, check the atmosphere for freshness and never fail to perform air
calibration.

- 29 -

5 How to Use

5-6. Setting value check5-6. Setting value check
Typical setting values can be checked by the following procedure.
In the user mode, setting values cannot be changed. When changing setting values, set them in themaintenance mode in P.44

1

2

In the user mode, press the˄ button twice.

Press the SET button.
Press the SET button to display
the first alarm setpoint.

<First Alarm Setpoint
Display>3

Press the ˅ or ˄ button tocheck the setting value.
<Second Alarm Setpoint
Display><Alarm Delay Time Display(seconds)><Zero Suppression Value
Display>
The zero suppression value
is displayed.

- 30 -

5 How to Use

5-6. Setting value check<Zero Follower ON/OFF
Display>
Not used.

<Air Pressure Correction
ON/OFF Display>
Whether air pressure
correction is enabled (ON) or
disabled (OFF) can bechecked.

<Alarm Summary Display>Press the SET button todisplay the gas
concentration and date/time
alternately as the alarm
history (up to 10 entries).

5

After checking the setting
value, hold down the MODE
button.
The monitor returns to themeasuring state.

- 31 -

5 How to Use

5-7. Power-off

5-7. Power-off
Slide the power switch down to power off.
After turning off the power switch of the monitor, turn off the power supply of the monitor.

CAUTION When the monitor is turned off, an alarm may be triggered on the upper (central) system.
Before turning off the monitor, the inhibit (point skip) on the upper (central) system must be
activated.
Decide whether the power can be turned off by checking the operation of the devices connected tothe external output or external contact output terminal of the monitor.

- 32 -

6 Alarm Activation and Functions

6-1. Gas alarm activation

6
6

Alarm Activation andFunctions6-1. Gas alarm activation
A gas alarm is activated when detected gas concentration reaches the preset alarm setpoint.

NOTE The alarm setpoint (first alarm and second alarm) is factory-set. The setting values can be changed in
the maintenance mode (P.44).
 Although the alarm delay time (standard: 1 second) works in the monitor to prevent a false activation,
it can be cancelled in the maintenance mode (P.44) if not needed.
 Alarm Pattern Setting: For self-latching (default), after an alarm is activated, press the MODE, ∧, ∨,or SET button to stop (reset) the buzzer. Alarm Pattern Setting: For auto-reset, the buzzer continues
to sound until the gas concentration drops below the alarm setpoint value.
 The alarm pattern setting can be changed in 2-44: Alarm Pattern Setting (P. 53).

Display operation<Gas Alarm Display (In case of oxygen deficiency state)>
The alarm display is a two-step alarm consisting of the first alarm display (ALM1) and the second alarm
display (ALM2).
It lights up in orange when concentration drops below the first alarm state (ALM1: 19.0%) or reaches its
alarm setpoint and in red when concentration drops below the second alarm state (ALM2: 18.0%) orreaches its alarm setpoint.
First alarm display

Second alarm display<Alarm Display at Over Scale>
If a gas alarm is activated when the concentration display is over scale (oxygen concentration exceeds
25.0%), the alarm display lights up as follows:

Concentration display
at over scale- 33 -

6 Alarm Activation and Functions

6-1. Gas alarm activation

Contact activation (Except for the dry battery type)
When gas concentration reach or is above the alarm setpoint value, the contact is activated.
Self-latching setting : The contact is activated when gas concentration drops below the alarm setpoint value.
The contact activation is reset automatically when MODE or ∧ or ∨ or SET button is pressed.
Auto-reset setting : When gas concentration drops below the set alarm value, the contact activation is reset
automatically.
Lock-in setting : Stop the buzzer with pressing MODE or ∧ or ∨ or SET button. Then, after gas
concentration drops below the alarm setpoint value, reset the contact activation with pressing MODE or ∧or ∨ or SET button.

WARNING If the MODE or SET button is pressed to enter another mode while an alarm is triggered, thecontact activation is reset.

"Alarm Pattern Example (Auto-reset, L-LL)"
Gas concentration

NormalAlarm

Recovered

Alarm

Recovered

SP.L side (1st)
SP.LL side (2nd)■ 1st alarm display■ 2nd alarm display■ 1st alarm contact■ 2nd alarm contact■ Buzzer"Alarm Pattern Example (Self-latching, L-LL)"
Gas concentration

NormalSP.H side (1nd)
SP.HH side (2st)Reset■ 1st alarm display■ 2nd alarm display■ 1st alarm contact■ 2nd alarm contact■ Buzzer- 34 -

6 Alarm Activation and Functions

6-1. Gas alarm activation

Reset■ 1st alarm display■ 2nd alarm display■ 1st alarm contact■ 2nd alarm contact■ BuzzerReset■ 1st alarm display■ 2nd alarm display■ 1st alarm contact■ 2nd alarm contact■ Buzzer

Reset

Reset

■ 1st alarm display■ 2nd alarm display■ 1st alarm contact■ 2nd alarm contact■ Buzzer

Reset

Reset

■ 1st alarm display■ 2nd alarm display■ 1st alarm contact■ 2nd alarm contact■ BuzzerReset■ 1st alarm display■ 2nd alarm display■ 1st alarm contact■ 2nd alarm contact■ Buzzer- 35 -

Reset6 Alarm Activation and Functions

6-1. Gas alarm activation"Alarm Pattern Example (Lock-in, L-LL)"
NormalGas concentration

Alarm

Recovered

SP.L side (1st)
SP.LL side (2nd)Buzzer Stop

Reset

Reset

■ 1st alarm display■ 2nd alarm display■ 1st alarm contact■ 2nd alarm contact■ Buzzer
Reset

Buzzer Stop

■ 1st alarm display■ 2nd alarm display■ 1st alarm contact■ 2nd alarm contact■ Buzzer
Buzzer Stop
Reset

Reset

■ 1st alarm display■ 2nd alarm display■ 1st alarm contact■ 2nd alarm contact■ Buzzer

Buzzer StopReset

■ 1st alarm display■ 2nd alarm display■ 1st alarm contact■ 2nd alarm contact■ Buzzer
Buzzer StopReset

■ 1st alarm display■ 2nd alarm display■ 1st alarm contact■ 2nd alarm contact■ Buzzer- 36 -

6 Alarm Activation and Functions

6-1. Gas alarm activation

Buzzer Stop

Buzzer Stop

Buzzer Stop

Buzzer Stop

Reset

Reset

■ 1st alarm display■ 2nd alarm display■ 1st alarm contact■ 2nd alarm contact■ BuzzerReset■ 1st alarm display■ 2nd alarm display■ 1st alarm contact■ 2nd alarm contact■ Buzzer

Buzzer Stop

Buzzer Stop
Reset

Reset

Buzzer Stop

Buzzer StopReset

■ 1st alarm display■ 2nd alarm display■ 1st alarm contact■ 2nd alarm contact■ Buzzer■ 1st alarm display■ 2nd alarm display■ 1st alarm contact■ 2nd alarm contact■ Buzzer
Buzzer Stop
Buzzer StopReset

■ 1st alarm display■ 2nd alarm display■ 1st alarm contact■ 2nd alarm contact■ Buzzer■：Acting※Only gas alarm action is a lock-in system.

- 37 -

6 Alarm Activation and Functions

6-2. Fault alarm activation

Response to gas alarm (In case of responding to leaked gas)
When a gas alarm is triggered, take actions in accordance with your management rules of gas alarm.
Normally, take the following actions.
• Check the reading of the monitor.
• If the gas alarm display continues to be displayed, close the main valve of the gas, and thencheck that the oxygen concentration reading is back to normal.

NOTE

 If an oxygen deficiency is momentary, the reading may already have returned to normal whenchecking it. In addition, when the alarm is triggered by noise or other incidental conditions other thana gas, the reading may have already returned to normal.

6-2. Fault alarm activation
A fault alarm is triggered when the monitor detects abnormalities. When a fault alarm is triggered, "FAULT"in the LCD display lights up in red.
An error message is displayed in the LCD. Determine the cause and take appropriate action.
Fault alarm display

After the monitor is successfully returned from the fault, it restarts with the process normally performed
right after it is turned on (initial clear).
If the monitor has problems and is repeatedly malfunctioning, contact RIKEN KEIKI immediately.

NOTE

 For information on malfunctions (error messages), see "Troubleshooting" (P.61).

- 38 -

6 Alarm Activation and Functions

6-3. External output operation

6-3. External output operation<Range:0-25vol% L-LL, L-H

4 - 20 mA Output Table>

InitialExternal output(4 - 20 mA)
17.4mA

External output(0 - 1 V)
0.84V

Normal

4.0 - 20.0mA

0 - 1V

Scale over

20.1mA -1V

TroubleMaintenance modemenu
Air calibration
Alarm setpoint check
Alarm summarycheck

21.5mA

1V

Fixed values
Depending on gas
concentration
Depending on gas
concentration
Fixed values

17.4mA

0.84V

Fixed values

17.4mA
17.4mA

0.84V
0.84V

Fixed values
Fixed values

17.4mA

0.84V

Fixed values

Date/time check andsetting

17.4mA

0.84V

Fixed values

Alarm test

4.0 - 20.0 mA

0 - 1V

Depending on test
value

Status<Range:0-50vol% L-LL, L-H

Remarks

4 - 20 mA Output Table>

InitialExternal output(4 - 20 mA)
10.7mA

External output(0 - 1 V)
0.42V

Normal

4.0 - 20.0mA

0 - 1V

Scale over

20.1mA -1V

TroubleMaintenance modemenu
Air calibration
Alarm setpoint check
Alarm summarycheck

21.5mA

1V

Fixed values
Depending on gas
concentration
Depending on gas
concentration
Fixed values

10.7mA

0.42V

Fixed values

10.7mA
10.7mA

0.42V
0.42V

Fixed values
Fixed values

10.7mA

0.42V

Fixed values

Date/time check andsetting

10.7mA

0.42V

Fixed values

Alarm test

4.0 - 20.0 mA

0 - 1V

Depending on test
value

Status- 39 -

Remarks

6 Alarm Activation and Functions

6-4. Suppression function<Range:0-25vol%, 0-50vol% H-HH

4 - 20 mA Output Table>

InitialExternal output(4 - 20 mA)
2.5mA

External output(0 - 1 V)
0V

Normal

4.0 - 20.0mA

0 - 1V

Scale over

20.1mA -1V

TroubleMaintenance modemenu
Air calibration
Alarm setpoint check
Alarm summary
check

0.5mA

0V

Fixed values
Depending on gas
concentration
Depending on gas
concentration
Fixed values

2.5mA

0V

Fixed values

2.5mA
2.5mA

0V
0V

Fixed values
Fixed values

2.5mA

0V

Fixed values

Date/time check andsetting

2.5mA

0V

Fixed values

Alarm test

4.0 - 20.0 mA

0 - 1V

Depending on test
value

StatusRemarks

6-4. Suppression function
The sensors integrated in the monitor are influenced by environmental changes (temperature, humidity andother characteristics) in no small measure, which affects the reading.
Therefore, the reading might be fluctuated near the atmosphere level even in a normal environment.
The suppression function is used to hide (suppress) the fluctuation of the reading under the setting value,indicating a level that can obscure influences by environmental changes around the atmosphere level.
This function can be set in the maintenance mode (P.44).

- 40 -

6 Alarm Activation and Functions

6-5. Correction processing function

6-5. Correction processing function
The sensor output for the monitor may vary due to the effects of solvent gases, noise, and environmental
fluctuations (such as temperature and humidity effects). The correction processing function corrects
reading variations within the normal range to 20.9% every hour.

6-6. Auto air calibration function
The monitor requires air calibration during daily and regular maintenance. Concentration readings may
deviate from "20.9%" due to factors such as output drift over time, even when operations are otherwise
normal. This function performs air calibration automatically, reducing the burdens involved in regularmanual air calibration for customers with monitors installed in multiple locations. Air calibration is
performed automatically every 720 hours (approximately 1 month) after confirming that the sensor output isstable.

NOTE Unless otherwise specified by the customer at the time the order is placed, the correction processing
function is enabled by default.
 Unless otherwise specified by the customer at the time the order is placed, the auto air calibration
function is enabled by default.
 The settings can be changed as follows to enable or disable the correction processing function andauto air calibration function as required:Open theupper case.
OX-600

DIP switch label
DIP switches

Sensor board- 41 -

Turn off the power and open theupper case. Check the DIP
switches on the sensor board.
1 AIR FOLLOWER
Correction processing
function
2 AUTO AIR CAL.
Auto air calibration function
Set the DIP switches to ON or
OFF as required, reattach theupper case, then turn on the
power.

7 Maintenance7-1. Maintenance intervals and items

7
7

Maintenance

The monitor is an important instrument for the purpose of safety.
To maintain the performance of the monitor and improve the reliability of safety, perform a regular
maintenance.

7-1. Maintenance intervals and items
This is a safety unit. Never fail to perform daily and regular maintenance before use.
••

Daily maintenance: Perform maintenance before commencing each work.
Regular maintenance: Perform maintenance once or more for every six months to maintain theperformance as a safety unit.
Maintenance
itemPower supply
check
Concentration
display check

Alarm test
Span
Adjustment
Gas alarm
check

Maintenance content
Check that the LCD display lights up.
The monitor requires air calibration
during daily and regular maintenance.
Concentration readings may deviate
from "20.9%" due to factors such as
output drift over time, even when
operations are otherwise normal.
Check that the concentration display
value is "20.9%".
When the reading is incorrect,
perform the air calibration after
ensuring that no other gases exist
around it.
Inspect the alarm circuit by using thealarm test function.
Perform span adjustment using acalibration gas.
Check the gas alarm using acalibration gas.

Daily
maintenance

Monthly
maintenanceRegularmaintenance































WARNING If an abnormality is found in the monitor, contact RIKEN KEIKI immediately.

NOTE The built-in sensor of the monitor has a validity period and must be replaced regularly.

- 42 -

7 Maintenance7-1. Maintenance intervals and items

About maintenance services
We provide services on regular maintenance including span adjustment, other adjustments andmaintenance.
To make the calibration gas, dedicated tools, such as a gas cylinder of the specified concentration and gas
sampling bag must be used.
Our qualified service engineers have expertise and knowledge on the dedicated tools used for services,along with other products.
To maintain the safety operation of the monitor, please use our maintenance service.
Typical maintenance services are listed as follows. Please contact RIKEN KEIKI for more information.

<Typical Maintenance Services>
Item
Power supply
check
Concentration
display check
Alarm test
Span adjustment

Gas alarm check

Cleaning andrepair of the unit
Unit operation
check
Replacement ofconsumableparts

Services
Checks the power supply voltage.
Checks that the LCD display lights up.
(Verifies that relevant points can be identified on the system.)
Verifies that the concentration display value is "20.9%" at the atmosphere level.
Performs the air calibration if the reading is incorrect.
Inspects the alarm circuit by using the alarm test function.
Checks the alarm display (Checks the activation each for ALM1 and ALM2.)
Checks the alarm activation such as a buzzer.
Performs span adjustment using a calibration gas.
Checks the gas alarm by using the calibration gas.
Checks the alarm. (Checks triggering of alarm when the alarm setpoint is reached.)
Checks the delay time. (Checks time to delay until the alarm is triggered.)
Checks the alarm display (Checks the activation each for ALM1 and ALM2.)
Checks the alarm activation such as a buzzer.
Checks dust or damage on the surface, cover or internal parts of the unit, andcleans or repairs such parts as needed.
(Visual diagnosis) Replaces parts which are cracked or damaged.
Operates the buttons to check the operation of functions and parameters, etc.
Replaces consumable parts, such as a sensor.

- 43 -

7 Maintenance7-2. Maintenance (regular maintenance) mode

7-2. Maintenance (regular maintenance) mode
The maintenance mode allows for checking the status of the monitor and adjusting and changing thesettings.

How to enter maintenance mode
To enter the maintenance mode, use the following procedure.

1

Keep the MODE button pressed (for three seconds) inthe measuring state.
The user mode is displayed.

2

In the user mode, press the ˄ button three times.

3

Press the SET button.

4

Hold down the SET button (for three seconds).

5

To select items in the maintenance mode, press the ˅ or
˄ button to display setting and check items.

The monitor enters the maintenance mode.

<Test Functions (2-0 TEST)>
Perform the following tests.
2-00: Gas test
2-01: Alarm test
2-02: Fault alarm test
2-03: Display test
2-04: Not used.
Refer to gas "Test functions" (P.47) for details.
<Air Calibration (2-1 ZERO)>
Perform the air calibration.
Refer to "Zero adjustment" (P.50) for details.

- 44 -

7 Maintenance7-2. Maintenance (regular maintenance) mode
<Span Adjustment(2-2 SPAN)>

Perform the span adjustment.
Refer to "Span adjustment" (P.51) for details.

<Zero/Span Initialization(2-3 SDEF)>
Not used.

<Environmental Setting(2-4 SET)>Specify the environmental settings.
2-40: Not used.
2-41: Not used.
2-42: Alarm Value Setting (AL-P)
2-43: Alarm Delay Time Setting (AL-D)
2-44: Alarm Pattern Setting (AL-T)
2-45: Zero Suppression Type Setting (SP-T)
2-46: Zero Suppression Value Setting (SAPP)
2-47: Not used.
2-48: External Output Adjustment (MA20)
2-49: Sensor Operation Start Setting (SSET)
2-4A: Date/Time Setting (DATE)
2-4b: Air Pressure Correction Setting ON/OFF (P-A)
2-4C: Not used.
2-4d: Buzzer ON/OFF Setting (BZZR)
2-4E: Gas Alarm Contact ON/OFF (AL-R)
2-4F: External Output Signal ON/OFF
2-4H: LCD Backlight ON/OFF (LCD)
2-4J: Alarm Type Setting
2-4L: Alarm Pattern Setting
Press the SET button and refer to "Environmental setting"(P.52) for details.

<Display Setting (2-5 DISP)>
Not used.

<Factory Mode Switching(2-6 FMODE)>
Not used.

- 45 -

7 Maintenance7-2. Maintenance (regular maintenance) mode

<User Mode Switching(2-7 UMODE)>The monitor returns to the user mode.
Press the SET button twice to return to the user mode.
Refer to "Return to user mode" (P.58) for details.

6

After checking the setting value, hold down the MODE
button.
The monitor returns to the measuring state.

WARNING After air calibration, hold down the MODE button to return to the measuring state.
The monitor automatically returns to the measuring state in 10 hours.

- 46 -

7 Maintenance7-2. Maintenance (regular maintenance) mode

Test functions
2-0 TEST
Press the SET button
to enter the test mode.

2-00 GAS
Press the SET button
to perform a gas test.
Similar to the detection
condition,the readingchanges and an alarmis displayed after gas
is introduced, but the“ALM1” and “ALM2” donot flash and thecontact is not
activated.
2-01 ALM
Press the SET button
to perform an alarmtest.
Use the ˅ button to
decrease the display
value to the alarm
setpoint to trigger an
alarm.
The external output
signal and contact
activation are enabled.
To disable them,specify the activation
setting for each in 2-4E
and 2-4F.
※Lock-in activation do notappear.

2-02 FALT
Press the SET button
to perform a fault
alarm test.
Use the ˅ or ˄ button
to enable the function
to trigger an alarm.

- 47 -

7 Maintenance7-2. Maintenance (regular maintenance) mode

2-03 LCD
Press the SET button
to perform a LCD
display test.
To disable the enabledfunction, use the ˅ or
˄ button to select it
and press the SET
button.
2-04 LCD
Not used.

- 48 -

7 Maintenance7-3. Preparation for zero and span adjustment

7-3. Preparation for zero and span adjustment
Perform zero and span adjustment of sensors using a calibration gas more than once every six months.
The zero and span adjustment requires dedicated equipment and a calibration gas. Please contact RIKEN
KEIKI.

<Required Equipment/Material>
EquipmentZeroadjustment
Spanadjustment

Calibration cap, gas sampling bag, pump, buffer, flowmeter
N2 (99.9 vol% or more): Zero adjustment, reading
accuracy 1, response time checkO2 (10.0 - 11.0 vol%): Reading accuracy check 2, alarm
delay time check

For details about operation,refer to "Zero adjustment"(P.50).
For details about operation,refer to "Span adjustment"(P.51).

Atmosphere AIR: Span calibration

Connect and configure the equipment as follows and put the calibration cap on the sensor part of themonitor.
Set the flow to 500±50 ml/min.

Pump
Flow meter

Buffer
Gas sampling bag

Supply a gas from theupper side of the calibration
cap.
Calibration cap

Exhaust a gas
from the side.
(Atmosphererelease)- 49 -

7 Maintenance7-4. Zero adjustment

7-4. Zero adjustment
Perform the preparation (P.49) before zero adjustment.
2-1 ZERO
Perform zeroadjustment.

Press the SET button
to display the current
concentration.

Supply a N2 gas(99.5% or more) to thesensor for threeminutes.

Press the SET button.

"PASS" is displayedwhen adjustment iscompleted, and "FAIL"
is displayed when it
fails.
If "FAIL" is displayed,
perform zeroadjustment again.
Zero adjustment willend.

- 50 -

7 Maintenance7-5. Span adjustment

7-5. Span adjustment
Perform the preparation (P.49) before span adjustment.
2-2 SPAN
Perform span (freshair) adjustment.

Press the SET button
to display the current
concentration.

Press theconcentration SET
button again. While theconcentration display
is blinking, use the ˅or ˄ button to adjust
the reading to "20.9%".

Press the SET button.

"PASS" is displayedwhen adjustment iscompleted, and "FAIL"
is displayed when it
fails.
If "FAIL" is displayed,
perform span
adjustment again.
Span (fresh air)adjustment will end.

- 51 -

7 Maintenance7-6. Environmental setting

7-6. Environmental setting
2-4 SETSpecify theenvironmental
settings.

2-40
Not used.

2-41
Not used.

2-42 AL-P
Set the alarm setpoint(first, second).
Use the ˅ or ˄ button
to set the alarm
setpoint and press theSET button to confirm
it.

- 52 -

7 Maintenance7-6. Environmental setting

2-43 AL-D
Sets the alarm delay
time (seconds).
Use the ˅ or ˄ button
to set the time andpress the SET button
to confirm it.
2-44 AL-T
Set the alarm patternsetting (Non latching(Auto-reset),
Self-latching).
nL: Non latching(Auto-reset)
L: Self-latching
Lc In:Lock-in
Use the ˅ or ˄ button
to select the setting
and press the SET
button to confirm it.

2-45 SP-T
Set the suppression
type.
Use the ˅ or ˄ button
to select the type andpress the SET button
to confirm it.

2-46 SAPP
Set the suppression
value (%).
Use the ˅ or ˄ button
to set the value andpress the SET button
to confirm it.

- 53 -

7 Maintenance7-6. Environmental setting

2-47
Not used.

2-48 MA20
Adjust the external
output (4 mA, 20 mA).
Use the ˅ or ˄ button
to set the value andpress the SET button
to confirm it.

When "AdJ" isdisplayed, connect anammeter. Then, use
the ˅ or ˄ button toadjust the value to 4
mA or 20 mA andpress the SET button
to confirm it.

2-48 MA20
The monitor returns toMA20.

2-49 SSET
Set the sensor
operation start.

- 54 -

7 Maintenance7-6. Environmental setting

2-4A DATE
Set the date/time.
Use the ˅ or ˄ button
to select each value inthe order of year,
month, day, hour andminute and press theSET button to confirm
it.

- 55 -

7 Maintenance7-6. Environmental setting

2-4b P-A
Set the air pressure
correction to ON/OFF.

2-4C
Not used.

2-4d BZZR
Set each of the firstand second alarmbuzzers to ON/OFF.

- 56 -

7 Maintenance7-6. Environmental setting

2-4E AL-R
Set the gas alarm state
contact to ON/OFF.

2-4F MA-O
Set the external output
signal during an alarm
test to ON/OFF.

- 57 -

7 Maintenance7-7. Return to user mode

2-4H LCD
Set the LCD backlight
to ON/OFF.

7-7. Return to user mode
2-7 UMOD
The monitor returns tothe user mode.

7-8. Consumables<Replacement of Batteries (for dry battery type)>
For how to replace batteries, refer to "Installation of batteries (for dry battery type)"(P.10).

- 58 -

8 Storage and Disposal

8-1. Procedures to store the monitor or leave it for a long time

88

Storage and Disposal

8-1. Procedures to store the monitor or leave it for along time
The monitor must be stored under the following environmental conditions.
• In a dark place under the normal temperature and humidity away from direct sunlight• In a place where gases, solvents or vapors, etc. are not present
Store the monitor in a shipping carton, if any, in which the product was delivered.
Store the monitor away from dust, etc. if the shipping carton is not available.

CAUTION If the monitor operating on dry batteries is not used for a long time, store it after removing thebatteries. Battery leaks may result in fire, injury, etc..

8-2. Procedures to relocate the monitor or use it again
When the monitor is relocated, refer to "How to Install" for relocation sites and wiring work.
The unpowered time must be minimized when the monitor is relocated.
When the monitor is used again after a long-period storage, perform a calibration.

CAUTION
 Contact RIKEN KEIKI for information on readjustment including calibration.

- 59 -

8 Storage and Disposal

8-3. Disposal of products

8-3. Disposal of products
When the monitor is disposed of, it must be treated properly as an industrial waste in accordance with thelocal regulations, etc.
If liquid is leaked from the sensor, do not touch the liquid. The sensor must be put into a plastic bag toprevent the liquid from leaking to the outside. If any liquid leaked from the sensor is found in the monitor
unit, turn off the power and contact RIKEN KEIKI immediately.

WARNING Do not disassemble the galvanic cell type sensor because it contains electrolyte.
Electrolyte may cause severe skin burns if it contacts skin, while it may cause blindness if its
contacts eyes. If electrolyte is adhered on your clothes, that part on your clothes is discolored or its
material is decomposed.
If contact occurs, rinse the area immediately with a large quantity of water.
 Dispose of batteries in accordance with a procedure specified by the local authority.

- 60 -

9 Troubleshooting

9 Troubleshooting

9
9Troubleshooting

The Troubleshooting does not explain the causes of all the malfunctions which occur on the monitor. This
simply helps to find the causes of malfunctions which frequently occur.
If the monitor shows a symptom which is not explained in this manual, or still has malfunctions even though
remedial actions are taken, please contact RIKEN KEIKI.
Symptom/Display

CausesThe power switch isturned off.

Actions
Turn on the power switch.

Abnormalities/momentary
blackout of power supply
systemThe power cannot
be turned on.

Abnormaloperations
Sensorabnormalities
E-1

Systemabnormalities
E-9 SYSTEM

The reading drops
and it remains so.

The main unit is notinstalled properly.
Cable abnormalities(open circuit/not
connected/short circuit)
The batteries are dead.
*Only for the dry battery
type
Disturbances by sudden
surge noise, etc.
The sensor is notconnected or improperly
connected.
Errors in communication
with the unit
The rated voltage is not
supplied to the monitor.
Abnormalities of ROM,
RAM or EEPROM inside
the monitor
Drifting of sensor output
Presence of interferencegas
Environmental changes

An oxygen
deficiency alarm istriggered despite of
no abnormalities at

Presence of interference
gas

Provide the rated voltage.
Take measures such as checking or adding the
UPS, power supply line filter and insulationtransformer.
Check whether the main unit is properly attached to
the wall-mounted unit.
Check the wiring of the monitor and related devices
around it.
Replace the two dry batteries.
Turn off and restart the monitor.
If a symptom like this is observed frequently, takeappropriate measures to eliminate the noise.
Check that the sensor is connected and theconnectors of the sensor unit board are securely
fastened.
Replace the sensor unit board with a new one.
Check the power supply, and supply the rated
voltage.
Please contact RIKEN KEIKI.
Perform the air calibration.
Disturbances by interference gases, such as
solvents, cannot be eliminated completely. For
information on actions, such as removal filter,
please contact RIKEN KEIKI.
Perform the air calibration. In particular, thegalvanic cell type is affected by the air pressure.
Disturbances by interference gases, such as
solvents, cannot be eliminated completely. For
information on actions, such as removal filter,
please contact RIKEN KEIKI.

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9 Troubleshooting
Symptom/Display
the detection point.

9 Troubleshooting
CausesActions
Turn off and restart the monitor.
If a symptom like this is observed frequently, takeappropriate measures to eliminate the noise.
When the environment (temperature, etc.) changes
suddenly, the monitor cannot adjust to it and isaffected by it.
In some cases, the monitor triggers an indication
alarm.
Because the monitor cannot be used under sudden
and frequent environmental changes, the user
should take some preventive actions to eliminatethem.

Disturbance by noise

Sudden change in theenvironment

Span adjustment
impossible

Deteriorated sensor
sensitivity
Improper calibration gas
concentration
Deteriorated sensor
sensitivity

Replace the sensor with new one.
Use the proper calibration gas.
Replace the sensor with new one.

- 62 -

10 Product Specifications

10-1. List of specifications

10
10

Product Specifications

10-1. List of specifications
Detection principle
Gas to be detected
Concentration display*1
Detection range
Display resolution
Detection method
Alarm setpoint
Accuracy of the reading

Galvanic cell type
OxygenLCD digital display (Three-digit, seven-segment/green, orange and red backlight)
0 - 25vol%/0-50vol%0 - 25vol%:0.1vol%/0 - 50vol%:0.5vol%
Diffusion type
Detection range 0 - 25vol%: 1st 19vol%(L)/2nd 18vol%(LL)[Standard]
Detection range 0 - 50vol%: 1st 18vol%(L)/2nd 25vol%(H) [Standard]Within ±0.7vol%(25vol% or less),±3.0vol%(25.1vol% or more)(under the same conditions)*2

Response time

90% response: within 30 seconds(under the same conditions)*2

Alarm delay time
(under the same conditions)*2

Accuracy of Alarm setpoint*2
Gas alarm typeGas alarm display
Gas alarm pattern
Gas alarm contact
Fault alarm/self diagnosis
Fault alarm display
Fault alarm patternContact capacity*3,4Transmission specifications*5
Cable for gas detector head
Power supply
Power consumption
Dry battery Continuous
operating time
Initial clear
Operating temperatures
Operating humidities
Operating pressure
Structure
Outline dimensions

For an oxygen deficiency alarm (18vol% L alarm), 5 seconds or less after detecting a 10 to11vol% gas
Difference between Alarm setpoint and indicated value of warning alarm are zero.
Two-step alarm (L-LL, L-H or H-HH)
1st: Lights up the concentration display and backlight (orange), buzzer
2nd: Lights up the concentration display and backlight (red), buzzer
Self-latching or Auto-reset, Lock-in
No-voltage contact 1a or 1b and normally de-energized (energized in response to an alarm)
System abnormalities/sensor connection abnormalities
Alarm detail display and backlight blinking (orange), buzzer
Self-latching
125VAC･1A or 30VDC･1A (Resistance load)
4 - 20mADC (no-insulation/load resistance under 300Ω) or 0 - 1VDC (no-insulation)
Dedicated cable for remote (3, 5, 10 or 20 m)
100 - 120VAC±10% (50/60Hz), 24VDC±10% or AA alkaline dry battery (2pcs.)
AC specification: Max. 5VA
DC specification: Max. 3W
Approx.1 year(25ºC, no alarm and no lighting, When using two AA alkaline dry batteries)

Approx. 25 seconds-10 - +40ºC (at a constant condition)
Below 90%RH (Non-condensing)
Atmospheric pressure (80kPa - 105kPa)
Wall mounting type, sensor integrated type or remote type
Main unit: Approx. 80(W)x120(H)x 35.5(D)mm
Remote sensor: Approx. 40(W)x96(H)x35.5(D)mm (projection portions excluded)
WeightAC specification: Approx. 200g/DC specification: Approx. 180g
Dry battery type: Approx. 230g/Remote sensor part: Approx. 55g (cable excluded)*1 No backlight during normal operation for the dry battery type.
*2 In conformity to JIS T8201 2010(Oxygen deficiency indicator) .
*3 No contact for the dry battery type.
*4 For CE/UKCA marking specifications, 30VDC, 1A (resistive load) only.
*5 Only 0～1VDC for the dry battery type. Some operations are different between the dry battery type and DC/AC specification.

- 63 -

10 Product Specifications

10-2. List of accessories

10-2. List of accessories• 3.2 m AC power cable (1 pc.) *Supplied only with AC specification• Cross-recessed pan head machine screw (2 pcs.)• Cross-recessed round head wood screw (2 pcs.)• Operating manual (1 pc.)

- 64 -

11 Appendix

11-1. Detection principle of galvanic cell type11
11

Appendix11-1. Detection principle of galvanic cell type
By immersing precious metal and lead in electrolyte and connecting them with a lead wire, a battery can bemade (galvanic cell).
When oxygen passes through the barrier, deoxidizing reaction occurs at the precious metal electrode while
oxidizing reaction occurs at the lead electrode.
The electric current generated by this reaction goes through load resistance (thermister), where it isconverted into voltage so that it can be read. When the oxygen concentration is decreased, deoxidizing
reaction at the precious metal electrode is also decreased, thus lowering the voltage at both ends of thethermister.
Barrier<Structure Diagram>

Negative
electrode
Electrolyte

Positive
electrod

Output terminal
Thermister

Important precautions
1. The readings of the monitor fluctuate slightly in response to changes in the air pressure. In particular,
be careful of alarm activation when a low air pressure is brought in by typhoon, etc.
In addition, it may be fluctuated by environmental (temperature, humidity, etc.) changes in the
installation site.
2. The alarm must be set within a range where the performance of the monitor can be ensured. The
standard alarm setpoint values are 18 vol% for the first and 19 vol% for the second.
3. This is a safety unit. This is not a control unit.
The alarm contact output of the monitor must be used for an external alarm lamp/buzzer, while theanalog signal output must be used for an indicator or external recorder. If these outputs are used tocontrol other units, we shall not be responsible for any malfunctions.
4. For maintenance of the monitor, it must go through a regular maintenance, including replacement andadjustment of the regular replacement parts as specified in the operating manual. In addition, because
this is a safety unit, it is recommended that a regular maintenance and span adjustment are performed
every six months.

- 65 -

11 Appendix

11-2. Definition of terms

11-2. Definition of terms
vol%Calibration
Maintenancemode

Initial clear

Zero
suppression
Alarm delay time

Gas concentration indicated in the unit of one-hundredth of the volume
Find relationship of the readings, display values or setpoints with the actual values
by using the calibration gas.
When maintenance is performed on the monitor, the alarm contact is disconnected,
and a signal to indicate the maintenance mode status is sent out to the external
output signal. As a result, maintenance can be performed on a single unit of themonitor.
The reading is unstable for seconds after the power is turned on. To prevent
malfunctions for that period, the alarm contact is deactivated. In addition, a signal toindicate the initial clear status is sent out to the external output.
A function to cut off the influences of environmental changes, interference gases,etc.
A function which temporarily suspends activation to prevent a false alarm caused bynoise from its outside.

- 66 -

11 Appendix

11-2. Definition of terms- 67 -

11 Appendix

11-2. Definition of terms- 68 -