Diffusion Type Gas Detector
KD-12 HART Series
Instruction Manual Keep this manual for easy reference.
 Carefully read this manual prior to use.
 This manual describes the standard model. If your unit contains customer-specificoptions, the delivery specifications will supersede this manual.

New Cosmos Electric Co., Ltd.
Instruction Manual No.
GAE-119-08
September 2022

 Unit Dimensions andComponents

 Sensor Unit Replacement
Pages 34 and 35

Pages 4 to 6

 Wiring
Pages 13 to 17

 Display and Operation
Modes
Page 19

 Maintenance, Operational
Checks/Procedures
Pages 25 to 33

 Troubleshooting
Page 36,37

Table of Contents
Introduction .................................................................................................................... 1
General Precautions...................................................................................................... 2
Package Contents ......................................................................................................... 3
Unit Dimensions and Components................................................................................ 4
4.1 Exterior Appearance ..................................................................................................... 4
4.2 Display and Controls..................................................................................................... 5
4.3 Terminal Block............................................................................................................... 6
Installation ..................................................................................................................... 7
5.1 Procedure ..................................................................................................................... 7
5.2 Typical Installation Locations ....................................................................................... 11
5.3 Installation of Optional Parts....................................................................................... 12
Wiring........................................................................................................................... 13
6.1 Guideline ..................................................................................................................... 13
6.2 Wiring/Connection ...................................................................................................... 14
6.3 Terminal Block Wiring Procedure ............................................................................... 16
Precautions before Use ............................................................................................... 17
Display at Power-up (Warm-up) .................................................................................. 18
Display and Operation Modes ..................................................................................... 19
HART Communication ................................................................................................. 20
10.1 Overview ................................................................................................................... 20
10.2 HART Communication Commands .......................................................................... 20
10.3 HART Communication Process ................................................................................ 22
Trouble Alarms ............................................................................................................ 23
Maintenance, and Operational Checks/ Procedures .................................................. 25
12.1 Routine Checks and Annual Inspection.................................................................... 25
12.2 Calibration Gas Preparation ..................................................................................... 26
12.3 Calibration ................................................................................................................. 28
12.4 Sensor Unit Replacement ......................................................................................... 34
Troubleshooting ........................................................................................................... 36
Specifications .............................................................................................................. 38
Warranty ...................................................................................................................... 40
Life Expectancy of Sensor .......................................................................................... 40
Service Life of Detector ............................................................................................... 40
Detection Principles ..................................................................................................... 41
Glossary ...................................................................................................................... 41

Introduction
 Thank you for purchasing the New Cosmos KD-12 HART series Diffusion Type Gas Detector.
 Please read the enclosed instruction to ensure safe and reliable operation.
 This gas detection unit detects various gas types including combustible gases. This unit isintended for use in industrial facilities (e.g. gas production plants and depots, chemical plants,
paint factories, and power plants) for the early detection of a gas leak and relaying the gas
concentration value as an analog 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
an external relay contact, thus helping prevent incidents such as fires, and explosions.
 Periodic maintenance is essential to maintain the reliability of your detection system. Performperiodic maintenance in accordance with the instructions given in this manual.

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 death orserious injury.

WARNING

Indicates a potentially hazardous situation that may result in death orserious injury.

CAUTION

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

NOTE

Provides information on product handling.

1General Precautions
 Carefully read this manual prior to use.
 To ensure safe operation, follow the precautions below.

DANGER

Be sure to ground the detector to prevent electric shocks.

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



The cable gland and blanking elements shall be ATEX/UKEx/IECEx-certified as“Flameproof Enclosure ‘db’”, and shall meet the special conditions below for safe use.
Installation in strict accordance to the Section 5.1 “Procedure” is required.

Special Conditions for Safe Use If used in an ATEX hazardous area, an ATEX-certified cable gland must be usedaccording to EN IEC 60079-0:2018 and EN 60079-1:2014. (Not included)
 If used in an UKEx hazardous area, it must be used a suitably certified cable gland for
UKEx requirements. (Not included)
 If used in an IECEx hazardous area, an IECEx-certified cable gland must be usedaccording to IEC 60079-0:2017 Edition 7.0 and IEC 60079-1:2014 Edition 7.0. (Notincluded) Fasteners (M5x16 hexagonal head screws) shall have yield stress of at least 450 N/mm2.
 Cable entry requirements for cable gland:
Thread size………………………… G3/4 or PF3/4
Minimum depth of engagement …. 10.86mm
Minimum thread engagement…….. 6 threads
 The dimensions of a flameproof joint between the case and the case cover of the KD-12
flameproof housing must meet the minimum requirements specified in EN/IEC60079-1.
Please contact the manufacturer for inspection, repair or adjustment of the flameproof
joint.

CAUTION

Wiring and installation should only be performed by a qualified electrician withknowledge of explosion proof components/installation.



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



Do not use the product in a place or near a place where silicone sealant/vapor may bepresent. Doing so may compromise the performance of the product.

Avoid using the product in an environment where it will be exposed to organic solvents
such as aromatic hydrocarbon or halogen hydrocarbon for extended periods.



Use a protective cover (sold separately) when installing outdoors.

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

2

Package Contents
This product is packed and shipped with the utmost care. If any items are missing or damaged,please contact New Cosmos or its distributor for replacement.
Package Contents

Optional Items

Gas detector

Protective cover
Horizontal type (KW-41A)
Vertical type (KW-42A)
2B pole mounting bracket (PB-1)
Sensor replacement jig (SK-1)
Calibration cap (GCP-09)
Gas calibration kit (Z-001K)
2-bulb hand pump
Capillary for 2-bulb hand pump

Accessory kit
M5x15 screws for wall-mounting: 2 pcs
M4x4 hexagonal set screw:
1 pc
Hex wrench (4 mm) : 1 pc
Instruction manual
Magnetic stick (MJ-1): 1 pc

*1

*2
*2
*2
*2

*1. One set per order: instruction manual.
*2. KD-12 optional items.

WARNING Do not use the magnetic stick for any purposes other than its intended use.
 Keep in mind that when the magnetic stick attracts magnetic objects, tools, iron pieces,
etc., your hands may be pinched and injured.
 For those allergic to metals, skin may become chapped or irritated if the magnet comes incontact with bare skin. If symptoms appear, do not touch the magnet.
 Magnets easily fracture and corrosion may form from the fractured surfaces.
Particles/chips may enter the eye and cause injury. Do not drop the magnetic stick orbump it against a hard surface.
 The components of the magnet may dissolve in water. Do not drink water exposed to themagnetic stick.
 Keep the magnetic stick away from electronic medical devices such as cardiac
pacemakers. Failure to do so may impair the normal operation of such devices.

CAUTION Keep the magnetic stick away from magnetic tapes, floppy disks, and bank/credit cards.
Failure to do so may magnetize them, making them unusable.
 Keep the magnetic stick away from high-precision devices such as personal computers
and watches. Failure to do so may cause a device failure.

3

Unit Dimensions and Components
4.1 Exterior Appearance(Dimensions are in mm)

Item

Component

Description/Function(1)

Case cover

---

(2)

Case

---

(3)

Sensor unit

Incorporates a built-in gas sensor.

(4)

Sensor guard

Protects the sensor unit.

(5)

Earth terminal (external)

Used for grounding the frame.

(6)

Status LEDs (3 places)(7)

Magnetic switches(4 places)(8)

Display(9)

Cable entry

(10)
(11)

M4x4 Hexagonal set
screw (2 places)
M5x16 Hexagonal headscrews (4 places)

Indicate the status of the unit:
power (green), alarm (red), and fault (amber)
Insert the magnetic stick into each magnetic switch
opening to operate.
Displays the gas concentration, parameter value andstatus message.
Thread size: G3/4 or PF3/4. Pitch=1.81mm.
Depth of engagement: 10.86mm.
Minimum engaged threads: 6 threads.
Applicable cable gland*1 must be provided by end user.
To secure the cable gland (cable fitting) and the sensor
unit. Use 2mm hex key wrench (not included).
To secure the case cover.
Use 4mm hex key wrench (included).

*1: Cable gland should be ATEX/UKEx-certified according to EN IEC 60079-0:2018 for use in an
ATEX/UKEx hazardous area, and EN 60079-1:2014, and IECEx-certified according to IEC
60079-0:2017 Edition 7.0 and IEC 60079-1:2014 Edition 7.0 for use in an IECEx hazardous
area.

4

4.2 Display and Controls

Magnetic Switches
Use the magnetic stick (MJ-1) to operate the magnetic switches.
Item

Component

Description/Function(1)[MODE] switch

Changes the operation mode or cancels the current
operation.

(2)[ENTER] switch

Confirms a setting or executes an operation.

(3)[UP] switch

Increases the parameter value.

(4)[DOWN] switch

Decreases the parameter value.

Item
(5)

Component

Description/Function
Displays gas concentration, parameter value and status
message.

Display

Status LEDs
Item

Component

Description/Function(6)[POWER] LED (green)

When lit, the unit is on.

(7)[ALARM] LED (red)When lit, alarm notification.

(8)[TROUBLE] LED (amber)

When lit, fault (device error) detected.

54.3 Terminal Block
Terminal Block+

Earth Terminal(Internal)

1
2
3
4
5

GasketSensor Connector

Item

Name

Description/Function

1

24 V (+)

Power supply voltage (positive)

2

GND

Power supply voltage (-) and analog signal (-) common

3

Signals

4-20mA analog and HART signals

4

ZA

5

ZC
Earth terminal(Internal)

External relay contact

Used for grounding the frame.

6

Installation
5.1 Procedure

WARNING The cable gland and blanking elements shall be ATEX/UKEx/IECEx-certified as“Flameproof Enclosure ‘db’”, and shall meet the special conditions below.
 If used in an ATEX hazardous area, an ATEX-certified cable gland must be usedaccording to EN IEC 60079-0:2018 and EN 60079-1:2014. (Not included)
 If used in an UKEx hazardous area, it must be used a suitably certified cable glandfor UKEx requirements. (Not included)
 If used in an IECEx hazardous area, an IECEx-certified cable gland must be usedaccording to IEC 60079-0:2017 Edition 7.0 and IEC 60079-1:2014 Edition 7.0. (Notincluded) Fasteners (M5x16 hexagonal head screws) shall have yield stress of at least 450
N/mm2.
 The dimensions of a flameproof joint between the case and the case cover of the
KD-12 flameproof housing must meet the minimum requirements specified in
EN/IEC60079-1. Please contact the manufacturer for inspection, repair or
adjustment of the flameproof joint.
 Cable entry requirements for cable gland and sensor:- Cable gland- Sensor

Thread size: G3/4 or PF3/4

Thread size: M27

Pitch: 1.81mm

Pitch: 1.5mm

Min. depth of engagement: 10.86mm

Min. depth of engagement: 8.25mm

Min. thread engagement: 6 threads

Min. thread engagement: 5.5 threads

 Securely tighten the hexagonal set screws to ensure that no movement of thecable gland is possible.
Cable entry requirements for cable gland and sensor:
Hexagonal set screws (2 places)
Screw Specifications
Size: M4x4
Screw length for securing cable gland: 3, 4, 5 or 6 mm
Screw length for securing sensor unit: 3 or 4 mmMaterial: Stainless steel

Note: The head of each screw shall be flush with the surface of the fitting.

7

CAUTION
 Be careful not to damage the gas detector during installation. Keep joint surfaces
clean and free from any damage. Contaminates such as scratches, fingerprints,
dirt and oil may adversely affect the explosion-proof characteristics of the device.
 Do not install the gas detector in the following conditions- Ambient temperature is outside of the specified operating temperature range(10C to 50C).
- Condensation prone areas.
- Exposure to water spray.
- Presence of acetylene gas- In the vicinity of equipment which can generate high frequencies or a magnetic
field.
- In environments where silicone sealant/gas is or may be used.


Install the gas detector in a place where it can be easily accessed formaintenance or inspection.

 Install the gas detector in a place free from vibration.
 Install the gas detector in a place free from sudden temperature changes.
 Avoid impacts to the gas detector.
 Attach the optional protective cover to the gas detector when installed outdoors.
 The installing height of the gas detector corresponds to the specific gravity ofthe target gas. Install the gas detector in accordance with required regulations.
 Install the gas detector in an environment where there is no power outage
including short interruptions.
 The contact uses a mechanical relay, which can activate if exposed to excessive
shock or vibration. Install the gas detector in a place free from shock andvibration. Set a delay time greater than one second for the external device
connected to the gas detector.

 Installing Height Regulation
Gas type
Gas heavier than air(e.g. LPG)

Installing height
Maximum of 10cm above thefloor (height to the sensor
guard tip)

Gas near the specificgravity as air(e.g. Carbon monoxide)

75 to 150 cm above the floor(height to the sensor guard tip)

Gas lighter than air(e.g. Natural gas andhydrogen)On or near the ceiling

8

Remarks
Keep a space of approx. 7 cm
from the sensor guard tip foreasy maintenance andinspection.
Determine the height byconsidering the specific gravityof the target gas and mounting
environment.
Determine the height byconsidering layout (e.g. scaffold)for easy maintenance.

 Secure the gas detector to the wall by tightening the two M5 screws (included) through themounting holes. Attach the protective cover (not included) when installing the detector
outdoors. Mount the detector with a 2B pole mounting bracket (not included) when mounting
the detector to a 2B pole. Refer to 5.3 “Installation of Optional Parts” for more information.

(Dimensions are in mm)

 The case cover of the detector needs be able to open during installation, wiring, or sensor
replacement. Make sure to keep sufficient space so that the cover can be opened to 90° or
more.

(Dimensions are in mm)

9

Maintain a distance of 50cm or more between the front of the detector and any other object
during installation and operation.

Maintain a distance of
50cm or more.

 When installing this diffusion-type gas detector in a high location, or on a ceiling, make sure toleave enough space below the detector to allow for inspection or maintenance activities. Wheninstalling the detector at a height more than 3m from the floor, we recommend using asuction-type gas detector with a sampling tube up to the ceiling.

Leave space below the gas
detector for inspection andmaintenance.

 When installing the detector in a high location, or on a ceiling, the sensor guard is notnecessary, but when installing the detector in a low location such as on a floor, make sure to
install the sensor guard to protect it from splashing water.
 Consider the directions of the gas flow and the hole of the sensor guard when installing thedetector.
Rotate the sensor guard tochange its direction so that the
openings are in line with gas
flow.

Gas flowSensor guard

105.2 Typical Installation Locations
 Install the gas detector in a place where gas is expected to accumulate.

Places where gas is likely to accumulate.
Gas detector
Doors and windows(Inlets and outlets)

Roof fan(Outlet)

Entrance(Inlet)Plan View

Side View
Indoor Installation

Partition
wall

Pipe
Valve

Gas detector

FlangeOutdoor Installation

11

5.3 Installation of Optional Parts
 Protective Cover
(190)

(90)

(90)

(190)
M3 screw(1 place)M3 screw(1 place)
(190)

(190)

(Dimensions are in mm)

Horizontal Type (KW-41A)

Vertical Type (KW-42A)

DANGER Secure the protective cover with M3 screw (1 place) when installing the gas detector in aplace subject to strong winds.

 2B Pole Mounting Bracket(Dimensions are in mm)

12Wiring
6.1 Guideline
 Use explosion-proof wiring when installing the detector in a hazardous area.

WARNING The cable gland and blanking elements shall be ATEX/UKEx/IECEx-certified as“Flameproof Enclosure ‘db’”, and shall meet the special conditions for safe use.
Installation in strict accordance to the Section 5.1 “Procedure” is required.

CAUTION Wiring and installation should only be performed by a qualified electrician withknowledge of explosion proof components/installation.
 Do not connect the power supply to the gas detector until wiring is completed and thecase cover is closed.
 Do not touch or let any tool (e.g. screwdriver, wrench) touch the inside surface of thecase or case cover, keep joint surfaces clean and free from any damage. Contaminates
such as scratches, fingerprints, dirt and oil may adversely affect the explosion-proof
characteristics of the device.

Cable Work
 Use a shielded twisted pair cable with 0.75 to 2.00 mm2 wires. Sheath all cables in a protective
tube, such as a metal conduit or carbon steel pipes, or other protective structure, such as ametal or concrete duct.
 When using the external relay contact function of the product, a five-conductor cable, with amaximum cable conductor diameter of 1.25 mm2 is required. If only the analog signal function
is used without the external relay contact function, then a three-conductor cable, with amaximum cable conductor diameter of 2.00 mm2, is required.
.

13

6.2 Wiring/Connection

WARNING

Before opening the case cover of the gas detector, be sure to eliminate possible sourceof ignition. Disconnect the power supply to the detector and all devices connected to it(e.g. indicator unit and signal converter).

Be sure to ground the gas detector to prevent an electric shock.



Use a conductor with a cross-sectional area of at least 4mm2 for external grounding.

Place a plain flat washer between the case and the terminal.

CAUTION

Connect wires to their corresponding terminals.



Keep the connection cable (power and signal lines from the detector) away from otherpower lines.

When closing the case cover, make sure that it does not catch on the gasket or any
loose cables and that the cables are not overly stressed.



Wire a current loop between Signal and Ground. If the wiring is open, normal gas
detection is impossible because a trouble alarm will be triggered.

Connecting Power and Signal Lines If needed, use dedicated breakers for power lines going to devices connected to the detector,
such as an indicator unit or a signal converter.
 Use a twisted pair cable that has 0.75 to 2.00 mm2 wires.
 Ensure that the power voltage supplied to the gas detector is within the specifications.
 Ensure that the load resistance of the signal line, including the resistance of the wire, is notless than 120 ohm and not more than 500 ohm.

14 The specifications for single wires/twisted wires/pins to be connected to the terminal block are
given below. Prepare wires/pins that comply with these specifications.
Stripped wire length (L) = 7mm- Single wire outer diameter: 0.2 mm2 to 4 mm22
2- Twisted wire outer diameter: 0.2 mm to 2.5 mm- Pin outer diameter without plastic sleeve: 0.25 mm2 to 2.5 mm2- Pin outer diameter with plastic sleeve(S) = 40mm
: 0.25 mm2 to 1.5 mm2- Stripped wire length (L) : 7 mm
- Total wire length from casing interior to terminal block (S): 40mmNOTE
 Single-point grounding (grounding at a single point) is mandatory. Grounding on the power
supply side (right side of the drawing) is recommended as shown in the drawing below.
[Typical Wiring Connection when Gas Detector is Grounded on Power Supply Side][Typical System Configuration]
4-20mA

Gas

KD-12(HART)+HART

Multip
lexer

DCS
or
PLC

HART Communication Control System Refer to the instruction manual of each device for full information.
15

Valves6.3 Terminal Block Wiring Procedure

CAUTION Do not apply the power supply to the gas detector until wiring is completed and the casecover is closed.
 Do not touch or let any tool (e.g. screwdriver, wrench) touch the inside surface of thecase or case cover, keep joint surfaces clean and free from any damage. Contaminates
such as scratches, fingerprints, dirt and oil may adversely affect the explosion-proof
characteristics of the device.

(1) Ensure that 24V power supply is used.
(2) To open the case cover, loosen the four hexagonal head screws located at the four cornersof the case cover using the 4mm hex wrench (included).
(3) Secure an appropriate cable gland (not included) to the gas detector with a hex key
wrench (not included). Feed the 3-wire cable (PWR+, GND, Analog 4-20mA) through thecable gland.

Cable gland (not included)(4) Insert a flat-head screwdriver (“Phoenix Contact ST-BW” flat-head screwdriver or
equivalent is recommended for user-friendliness) into the slot in the upper row of theterminal block, and lift up the screwdriver. Next, push the screwdriver further into the slot tolock the corresponding slot on the lower row in the open position. Now the screwdriver islocked in place and does not need to be held. While the screwdriver is in this position, thecorresponding slot is open.
Terminal block(5) Insert the tip of each wire into its corresponding slot.
Connect the (PWR+) wire to the slot marked “24V(+)”. Connect the (GND) wire to the slot
marked “GND”. Connect the (Analog 4-20mA) wire to the slot marked “Signal”.

16(6) Remove the screwdriver from the slot to close it. This will securely connect the wire to theterminal.
(7) Check that these three wires are secure in their corresponding terminals.
(8) Additional wiring for the external relay contact can use the slots marked “ZA” and “ZC”.
(9) Close the case cover. Attach the case cover to the case by tightening the four hexagonalhead screws at the four corners of the case cover with the hex wrench (yield stress of atleast 450 N/mm2).

Precautions before Use
CAUTION Before turning on any of the devices connected to this product (e.g. indicator unit, signal
converter), check that all wiring is correct, particularly the gas detector and indicator unit
or signal converter.

 In Case of Gas Leakage

DANGER Remain calm and check that there is no fire present. Do not touch any electric switches
under any conditions. Sparks caused by turning on or off electric switches may cause an
ignition.

DANGER If there is a gas leak alarm, take the necessary measures specified by your company.
 If a gas leak occurs indoors, open the windows and doors to ventilate the room.
 Identify the location of the gas leak, and promptly take the necessary measures.
Measure the gas concentration with a portable gas detector, and confirm the detection
site is safe before entering.

17

Display at Power-up (Warm-up)
CAUTION Check that there is no gas present before turning on the product When the sensor output is not stable, the external relay contact may possibly activate. To
prevent possible activation of the external relay contact during the warm-up, release theinterlocks of the external devices, if needed.
 During the warm-up, the analog signal is fixed at 2.0 mA (default).

NOTE
 The magnetic stick is not usable during the warm-up.
 The warm-up cycle lasts approx. 30 seconds once the unit is powered.

(1)

Once the unit is powered, the warm up process will begin. All the status LEDs (green,amber and red) and the display will be lit.

(2)

While the status LEDs (green, red, and amber) are lit, the display shows the following
messages for one second each in the order below.
Software version number (installed in this gas detector)
Full scale value
Example: [] ppm is displayedwhen the full-scale value is 2000 ppm.
Alarm set value
Example: [] ppm is displayedwhen the alarm set value is 500 ppm.

(3)

The POWER LED (green) flashes for approx. 25 seconds.

(4)

When the flashing POWER LED (green) becomes solid, the warm-up cycle of the detector
is completed and the detector is now in gas monitoring mode.

NOTE If the sensor unit has not been energized for a long time of period (e.g. from factory to initial
power-up), it may take some time for the sensor output to stabilize.
 If needed, energize the gas detector for approx. one week, and perform the zero and span
adjustments before use. Refer to 12.3 “Calibration” for adjustments.

18

Display and Operation Modes
When the alarm set value is exceeded
Maintenance mode
Power-up(Warm-up)Green LED
flashing

Gas monitoring
mode

Green
LED ison

Red
LED
flashing

Gas
monitoring
mode

Test modeGreen
LED ison

Test mode

Red LED
flashing

Red LED
flashingGreen LED
is on

Display[Gas
concentration
value isdisplayed.

Analogsignal4-20 mA

Relay
Contact
operation(Normally
Open)

HART
signalGas
concentration isdisplayed.

]

[

]

[Set
concentration]
Test from 10% to110% of full scaleis possible.

[Gas
concentration][Test value]

Displayedalternately

Displayedalternately

Test value or
fixed value(1.6 mA) is aselectable
output.

Fixed at 2.0mA
or 4.0mA

Gas
concentration
value is output.

Test value is
outputGas
concentration
value or fixedvalue (1.6mA) is aselectable
output.

Not activated.

Activated

Activated

Not activated.

Not activated.

(Open)(Closed)(Closed)(Open)(Open)

EnableEnableEnableEnableEnable19

HART Communication
10.1 Overview
 This gas detector can superimpose a low-level digital signal over a 4-20mA analog signal andtransmit these signals simultaneously over the same wiring to the host system.
 This gas detector does not support a burst mode. For this reason, the gas detector sends asignal only when it receives a command from the host system.
 Install the latest version of the DD file into the host system.
Note: The DD file is not included in this package. The latest version is available from theFieldComm Group website at:(http://www.hartcommproduct.com/inventory2/index.php?action=memberdirectory&num=463).

10.2 HART Communication Commands
There are three classes of commands for the HART communication, universal commands,
common practice commands and Device Specific commands.
Command class
Universal

Common PracticeDevice SpecificDescription
All devices using the HART
protocol must recognize andsupport the universal
commands.
Common Practice commands
provide functions implemented
by many, but not necessarily all,
HART Communication devices.

Device Specific commands
represent functions that are
unique to each field device.

Remarks
Refer to the Universal Command
Specification, which is available fromthe FieldComm Group website.
The commands (Nos.38, 40, 42, 45,
46 and 59) are implemented.
Refer to the Common PracticeCommand Specification, which isavailable from the FieldComm Groupwebsite.
Refer to the table below.

In addition to the requisite HART communication commands, device-specific commands are alsoavailable. Refer to the table below.
List of Device-specific Commands
No.
128

CommandSet write protection

129
130
131
132

Read dynamic variable
Read ADC value
Read gas concentration
Read peak values

133

Reset peak values

134

Read 4-20mA compensation values

FunctionSet the software write protection to prevent
unexpected writing to the detector by the host.
Read the dynamic variable used by the detector.
Read the Analog-to-Digital Converter value.
Read the gas concentration value.
Read the lowest and highest values of measured
gas concentration.
Reset the lowest and highest values of measured
gas concentration.
Read the slope and intercept coefficients for
4-20mA compensation.
20

No.

CommandFunction

135

Write 4-20mA compensation value A

136

Write 4-20mA compensation value B

137
138

Read calibration parameters
Write potentiometer value

139

Write rough adjustment offset

140

Write span coefficient141

Write virtual zero point

142

Read test value

Write the slope coefficient for 4-20mA
compensation.
Write the intercept coefficient for 4-20mA
compensation.
Read the calibration parameter values.
Write the digital potentiometer value. The range is
0 to 127.
Write the rough zero adjustment offset value. The
range is 0 to 254.
Write the span coefficient. The range is 572 to1428.
Write the virtual zero point value. The range is 150
to 450.
Read the test value for use in the test mode.

143
144
145
146
147
148
149
150

Write test value
Read alarm and trouble
configuration
Write alarm value
Write alarm delay
Read trouble value
Write trouble delay time
Write alarm hysteresis
Read alarm mode and special mode.

151
152

Write alarm mode
Write special mode

153
154

Read linear code
Write linear code

155
156
157

Read linear data table
Write linear data table
Read current linear data table

158
159

Read full scale
Write full scale

160

Write decimal point

161

Read power-up (warm-up) time

162
163

Write power-up time
Write power-up current

164

Read zero suppression

Write the test value for use in the test mode.
Read the set parameters for alarm and trouble(fault).
Write the alarm set value.
Write the alarm delay time.
Read the trouble (fault) set value.
Write the trouble (fault) delay time.
Write the alarm hysteresis range.
Read the alarm mode. Read “0” for the special
mode. “0” is normally unused.
Turn on the alarm mode.
Turn on the special mode (Write “0” for the special
mode, which is normally unused.)
Read the linear code from ROM.
Write the linear code to ROM. The range is 0 to 40
and 255.
Read the linear data table of ROM.
Write linear data to the linear data table of ROM.
Read the linear data table, currently in use, from
ROM.
Read the full scale value.
Write the full scale value. The range is 10 to9999.
Specify the decimal point to display. The range is0, 1, 2, 3 or 4.
Read the power-up time and the power-up current(2.0mA or 4.0mA).
Set the power-up time.
Write the current code at power-up. (0: 4.0 mA, 1:
2.0 mA)
Read the zero suppression values, both positive
and negative.
21

No.

Command165

Write zero suppression

166
167
168
169
170
171
172

Read sensor voltage
Write sensor voltage
Read maintenance mode
Write maintenance mode
Read unit code
Write unit code
Read other parameters

180

Read adjustment status

181
185

Execute adjustment
Read firmware version

249

Write monitor command

250

Write device ID No.

Function
Write the zero suppression values, both positive
and negative.
Read the voltage applied to the sensor.
Write the voltage applied to the sensor.
Read the maintenance mode status.
Turn on or off the maintenance mode.
Read the unit code (0: %LEL, 1: ppm).
Write the unit code (0: %LEL, 1: ppm).
Read other parameters.
Read whether a gas adjustment was normallycompleted.
Execute zero adjustment or span adjustment.
Read the firmware version of main and HSM
boards.
Send monitor command used for serial
communication and execute.
Write the device Identification number.

10.3 HART Communication Process In HART communication, the 4-20mA signal line (twisted pair cable) is connected to themaster device (host system).
 It is possible to use up to two master devices (primary and secondary). Typically, a Distributed
Control System (DCS) is used as a primary master and a hand-held communicator is used asa secondary master.
 This gas detector does not support a burst mode, and will not respond unless it receives acommand from a master device.
 A slave device (gas detector) will respond to the corresponding command from the masterdevice (host system) with the DD file installed.

22Trouble Alarms
 This product has a self-diagnosis function, and a trouble (fault) alarm will activate if a problem
is found.
 This product alerts the user of a problem by showing the corresponding error code on thedisplay when a trouble alarm activates. The error codes are listed in the table below.
 When a trouble alarm activates, the 4-20mA analog signal is fixed at 1.6mA.
Error codeon display

amber
TROUBLE
LED

ProblemFlashing

Power supply
voltage drop

Probable cause

Solution

Insufficient power
supply voltage

Check the power supply
voltage.

Flashing

Sensor error

Sensor connector
disconnected ordamaged sensor wire

Check that the sensor
connector is securely
connected.
If the sensor connector
is defective or if the wireis damaged, contact
New Cosmos or its
authorized
representative forrepair.

Off

Zero point
adjustment error

Gas is present in theambient air

Perform zeroadjustment in clean air.

.

Off

Span adjustment
error

Incorrect gas type
and/or concentration
used for adjustment

Check the gas type andconcentration ofcalibration gas. If they
are incorrect, replace
the gas with correctone. Perform fine span
adjustment with thecorrect calibration gas.
Check the gas type andconcentration ofcalibration gas. If they
are correct, perform
coarse span
adjustment.

Flashing

Flashing

Internal circuit
errorInternal circuit
errorInternal failure

Contact New Cosmos
or its authorized
representative forrepair.

Internal failure

Contact New Cosmos
or its authorized
representative forrepair.

23

Error codeon display

amber
TROUBLE
LED

ProblemFlashing

Analog output
error

Flashing

Internal circuit
errorFlashing

Internal circuit
errorFlashing

Maintenancemode recovery
error

Probable cause

Solution

Damaged wire orinternal failure

Check the wires forcorrect connection. If
wires are correctly
connected, there may
be a damaged wire orcomponent failure. Inthat case, contact New
Cosmos or its
authorized
representative forrepair.

Internal failure

Contact New Cosmos
or its authorized
representative forrepair.

Internal failure

Contact New Cosmos
or its authorized
representative forrepair.

Gas detector remains inmaintenance mode.

Power-cycle the gas
detector by turning thepower off, and waiting a
few seconds thenturning back on.

 If a code other than the ones listed is displayed, refer to 13 “Troubleshooting”. If the productdoes not reset to normal operation after taking the steps shown in the table or if your problem
is not listed in the table, please contact New Cosmos or its authorized representative.
 If the detector goes into any unintended mode during adjustment or setting, cease using thedetector and consult with your system administrator.

24

Maintenance, and Operational Checks/ Procedures
12.1 Routine Checks and Annual Inspection
 Routine checks are carried out by the user, while annual inspections are performed by New
Cosmos or its authorized representative.
Frequency

Item

Min.1 permonth

Visual check

Procedure Check that POWER LED (green) is lit.
 Check that gas concentration value isdisplayed.
 Check wire element (mesh) of sensor unit for
clogging or corrosion.
 Check gas detector for corrosion.
 Check mounting screws for corrosion.
Replace any worn or damaged parts.
Apply the calibration gas to the gas detector
and check the operation of the alarm.
 Attach the calibration cap to the detector,
apply calibration gas, and check theoperation of the alarm.

Routinecheck

Every twomonthsCheck Alarm
operation by using
actual gas sample

Calibration gas
gas
Calibration
Calibration cap

Check that the detector is free from objects that
may interfere with the gas diffusion.

Detector vicinity

Annualinspection

Min.1 peryear

Contact New Cosmos or its authorized representative for inspection.

 Use optional items (e.g. calibration cap, gas calibration kit) when actual gas is used forcheck.

Important Notice for Annual Inspection
In order to ensure the reliability of this gas detection and alarm system, it is vital to performperiodic maintenance and inspections. Further, it is necessary to carefully perform inspection
and calibrations by using actual gas (combustible or poisonous gas). It is highly
recommended that a maintenance contract with a New Cosmos local representative bemade for the performance of annual inspections.
Installation, inspection, maintenance, calibration and proof testing shall only be performed bytrained personnel.

25

12.2 Calibration Gas Preparation
 Prepare calibration gas (actual gas) for inspection or maintenance use.
 Typical method to prepare calibration gas, 0.72 vol% (40%LEL) isobutane, is given below as
an example.

When a commercially prepared gas cylinder is available,

Commercially preparedgas cylinder 0.72 vol%air balance

Completely remove air from a gasbag, because if residual air remains inside the bag before
filling, it will cause an incorrect measurement. Fill the prepared gas into the gasbag asshown in the drawing below.

GasbagNOTE

Use a urethane gasbag. Leave the gas inside the bag for approx. 30 minutes before
use, allowing the humidity of the gas inside to become close to the ambient humidity.

26

When a commercially prepared gas cylinder is not available,
Use a gas calibration kit (not included) and a pure gas cylinder (isobutane at 99 vol% ormore). Dilute pure isobutane with air to produce 0.72 vol% (40%LEL) calibration gas.
NOTE

Inexact calibration gas can be used for checking the alarm operation. Whencalibrating the detector, the gas concentration must be checked with a calibrated gas
detector (e.g. New Cosmos portable gas detector, Model: XP-3110) before thecalibration.

DANGER
Ensure that there is no open flame or source of ignition when handling a flammable gas whose
concentration exceeds its lower explosive limit (LEL).

(1) Connect a gasbag to a pure gas cylinder. Draw the neededamount of gas from the cylinder into the gasbag. Bend thetube of the bag and pinch it using a pinchcock to ensure aleak-proof seal.
(2) Connect a 10ml syringe to the gasbag. Collect 7.2ml ofpure gas into the syringe. (You can collect a little morethan needed, then discharge the excess to obtain 7.2ml.)(3) Connect the syringe to the inlet port of a measuring pump.
Pull the plunger of the pump drawing the gas into thepump. Remove the syringe from the inlet port. Pull theplunger of the pump to the limit (100ml).

vinyl tube

pure gas cylinder
Keep it upright.

(1)

pure gas ingas bagpure gas (7.2ml)

Pull syringe plunger(2)(4) Connect an empty gasbag to the outlet port of the pump.
Push the plunger of the pump. Cycle the plunger of thepump nine times to inflate the bag with the diluted gas.
For example, collect 7.2ml of pure isobutane gas, thencycle the plunger 10 times. (100ml per push), yielding a
0.72 vol% gas or 40%LEL gas:syringemeasuring pump

(3)
air

7.2ml / (100ml×10) =0.0072 (0.72vol % diluted gas).
The LEL of isobutane is 1.8vol%.

measuring pump

0.72/1.8×100=40 (40%LEL diluted gas)
diluted gas ingasbag27(4)

12.3 Calibration
 Maintenance Mode

DANGER During the maintenance mode, the external relay contact does not operate even if gas
concentrations reach or exceed the alarm set value. The detector in the maintenancemode maintains this status and the display shows []. The maintenance modeis canceled by turning off the detector after taking the steps (1) to (4) below, or
automatically cancelled after an 8 hours waiting period. Ensure that the detector is notleft in the maintenance mode as gas detection will not be possible for 8 hours when it willautomatically reset.

NOTE
 Use the magnetic stick for the switch operation.
 Carefully handle the magnetic stick during operation or setting, because it has a strong
attractive force. Refer to 3 “Package Contents” for full information.

(1)

While in the gas monitoring mode, press the MODE switch, then press the UP switch withinapprox. 2 seconds.

(2)

The detector displays
E.g.

first, followed by a number.

is displayed when the power-up operation has been completed and nofurther operation has been done.

(3)

If the numbertois not displayed, press the UP or DOWN switch to set the value.

(4)

Press the ENTER switch.

(5)

Ifand the gas concentration value are alternately displayed, the detector is
now in maintenance mode.

(6)

While

(7)

The maintenance mode can be canceled by performing the steps (1) to (4) above thenturning off the detector, or by waiting for 8 hours.

is displayed, the maintenance mode is still ongoing.

28

 Zero Adjustment
NOTE
 To prevent possible activation of the external relay contact during the zero adjustment, set thedetector to maintenance mode, if needed.
 Perform the zero adjustment in a place where there is no target or interfering gas in theambient atmosphere.
 Use the magnetic stick for the switch operation.
 Carefully handle the magnetic stick during operation or setting, because it has a strong
attractive force. Refer to 3 “Package Contents” for full information.

(1)

While in the gas monitoring mode, press the MODE switch, then press the UP switch withinapprox. 2 seconds.

(2)

The detector displays(3)

If the number

first, followed by a number.
is not displayed, press the UP or DOWN switch to set the value to.

(4)

Press the ENTER switch.

(5)

When the following messages are displayed, the zero adjustment is complete.

↓

↓

(6)

Upon completion of the zero adjustment, the detector will automatically return to the gas
monitoring mode.

NOTE If an error code is displayed, refer to 11 “Trouble Alarms”.

29 Fine Span Adjustment

CAUTIONTo prevent possible activation of the external relay contact during the fine span
adjustment, set the detector to maintenance mode or release the interlocks of theexternal devices, if needed.
 Only New Cosmos technician or personnel who have completed a maintenance seminarcan perform a span adjustment.

NOTE
 Make sure to complete a zero adjustment before performing fine span adjustment.
 Use the magnetic stick for the switch operation.
 Carefully handle the magnetic stick during operation or setting, because it has a strong
attractive force. Refer to 3 “Package Contents” for full information.

(1)

Attach a gasbag with the corresponding calibration gas to the gas detector. Apply gas at aneven flow using 2-bulb pump and capillary (not included) or equivalent.

Apply calibration gas
Calibration cap(2)

Allow time for the sensor to become exposed to the gas.

(3)

While in the gas monitoring mode, press the MODE switch, then press the UP switch
within approx. 2 seconds.

(4)

The detector displays(5)

If the number
tofirst, followed by a number.
is not displayed, press the UP or DOWN switch to set the value.

(6)

Press the ENTER switch.

(7)

The detector displays(8)

Press the UP or DOWN switch of the detector to adjust the display of the detector to theactual calibration gas concentration.

(9)

Press the ENTER switch.

first, followed by the present gas concentration.

(10) Fine span adjustment is complete whenis displayed.

(11) Upon completion of the fine span adjustment, the detector will automatically return to thegas monitoring mode.
(12) Remove the gasbag.
NOTE
 Perform coarse span adjustment if

or If an error code is displayed, refer to 11 “Trouble Alarms”.
30

is displayed.

 Coarse span adjustment
Perform coarse span adjustment, if

oris displayed.

CAUTIONTo prevent possible activation of the external relay contact during the coarse span
adjustment, set the detector to maintenance mode or release the interlocks of theexternal devices, if needed.
 Only New Cosmos technician or personnel who have completed a maintenance seminarcan perform a span adjustment.

NOTE
 Use the magnetic stick for the switch operation.
 Carefully handle the magnetic stick during operation or setting, because it has a strong
attractive force. Refer to 3 “Package Contents” for full information.

(1)

Attach a gasbag with the corresponding calibration gas to the gas detector. Apply gas at aneven flow using 2-bulb pump and capillary (not included) or equivalent.

(2)

Allow time for the sensor to become exposed to the gas.

(3)

While in the gas monitoring mode, press the MODE switch, then press the UP switch withinapprox. 2 seconds.

(4)

The detector displays(5)

If the number
value tofirst, followed by a number.
is not displayed, press the UP or DOWN switch to set adjust the.

(6)

Press the ENTER switch.

(7)

The detector displays(8)

Press the UP or DOWN switch to set the displayed value closest to the actual calibration
gas concentration.

(9)

Press the ENTER switch.

first, followed by the present gas concentration.

(10) Coarse span adjustment is complete whenis displayed.

(11) On completion of the coarse span adjustment, the detector will automatically return to thegas monitoring mode.
(12) Remove the gasbag.

NOTE
 Precise adjustment is not possible using coarse span adjustment only. Perform a fine span
adjustment once the coarse span adjustment is complete.
 If an error code is displayed, refer to 11 “Trouble Alarms”.

31 Full-scale and Alarm Set Values Display
NOTE
 The full-scale and alarm set values are only displayed and cannot be changed by the user.
 Use the magnetic stick for the switch operation.
 Carefully handle the magnetic stick during operation or setting, because it has a strong
attractive force. Refer to 3 “Package Contents” for full information.

(1)

While in the gas monitoring mode, press the MODE switch, then press the UP switch withinapprox. 2 seconds.

(2)

The detector displays(3)

If the number
tofirst, followed by a number.
is not displayed, press the UP or DOWN switch to set the value.

(4)

Press the ENTER switch.

(5)

The following messages are displayed in the order below so that the user can check thefull-scale and alarm set values.

↓↓
Full Scale value↓↓
ALarm set t value(6)

After the full-scale and alarm set values are displayed, the detector will automatically returnto the gas monitoring mode.

32 Test Mode Test mode is used to set the test value.

CAUTIONTo prevent possible activation of the external relay contact during the test mode, set thedetector to maintenance mode or release the interlocks of the external devices, if needed.

NOTE Use the magnetic stick for the switch operation.
 Carefully handle the magnetic stick during operation or setting, because it has a strong
attractive force. Refer to 3 “Package Contents” for full information.

(1)

While in the gas monitoring mode, press the MODE switch, then press the UP switch withinapprox. 2 seconds.

(2)

The detector displays(3)

If the number
to
.

(4)

Press the ENTER switch.

(5)

The following messages are displayed in the order below.

first, followed by a number.
is not displayed, press the UP or DOWN switch to set the value↓
Test value
Tests are possible with a concentration range from 10% to 110% of the full-scale value.
For example, if the full scale is 2000 ppm, the test is possible using a range from 200 to
2200 ppm. If the full scale is 100%LEL, the test is possible using a range from 10%LEL to
110%LEL.

(1)

Press the UP or DOWN switch to set the value to your desired calibration gas
concentration. The test will automatically start once the value is set.
If the set value is outside the operating range,orwill be displayed.

(2)

To end the test mode, press the ENTER or MODE switch.

(3)

Ending the test with the ENTER switch will save the tested value.
Ending the test with the MODE switch, will save the previously saved value.

33

Sensor Unit Replacement
WARNING Disconnect the power supply to the gas detector before replacing the sensor unit. Failure
to do so may cause a source of ignition.
 Before turning on the detector, ensure that the sensor and the sensor connector are
firmly connected to the detector. Proper gas detection is not possible if the sensor andthe detector are incorrectly connected.
 The dimensions of a flameproof joint between the case and the case cover of the KD-12
flameproof housing must meet the minimum requirements specified in EN/IEC60079-1.
Please contact the manufacturer for inspection, repair or adjustment of the flameproof
joint.
.

CAUTION？
 Only New Cosmos technician or personnel who have completed a maintenance seminar
can replace the sensor unit.
 Handle the sensor unit with care. Failure to do so may result in broken components suchas the sensor wire or in a failure of the sensor.
 When the sensor output becomes unstable while replacing the sensor unit, the external
relay contact may possibly activate. To prevent possible activation of the external relay
contact during the replacement, release the interlocks of the external devices, if needed.
 When removing or installing the sensor unit, take care not to twist the harness of thesensor connector.
 When closing the case cover, make sure it does not catch on the gasket or any loose
cables.

34

Sensor unit

Sensor replacement jig

Sensor guard(1)

Disconnect the power supply to the gas detector.

(2)

Loosen the four hexagonal head screws at the four corners of the case cover with the 4mm
hex wrench (included), and open the case cover of the detector.

(3)

Pull and disconnect the sensor connector.

(4)

Remove the sensor guard.

(5)

Use the sensor replacement jig to turn and pull out the sensor unit.

(6)

Insert a new sensor unit and tighten the sensor unit with the sensor replacement jig.

(7)

Connect the sensor connector.

(8)

Check that the sensor connector is securely connected.

(9)Attach the sensor guard.

(10) Close the case cover and tighten the four hexagonal head screws at the four corners of thecase cover with the 4mm hex wrench.
(11) Connect the power supply to the gas detector.
(12) After sensor unit replacement, it is necessary to keep the detector energized for approx.. 1
week for sensor stabilization, then perform zero and span adjustments.
(13) Prior to a span adjustment, make sure to complete a zero adjustment(14) If an error code is displayed, refer to 11 “Trouble Alarms”.
NOTE The sensor replacement jig is optional.

35

Troubleshooting Before requesting repair, please refer to the table below. If the detector does not return tonormal after performing the corresponding steps in the table, or if your issue is not found in thetable, consult New Cosmos or its authorized representative.
 If the gas detector goes into any unintended mode during adjustment or setting, cease using
the detector and consult with your system administrator.
Problem

Probable cause

POWER LED(green) does
not turn on.

Steps

Incorrect wiring

Check and rewire.
Check the power
supply voltage.

Low voltage state

Check that the sensor
connector is securely
connected.

TROUBLE LED (amber) is
flashing and error code isdisplayed.

Gas concentration value
andare flashingalternately.

External relay contact
does not function (noalarm signal to external
equipment)

Analog signal does notchange.

Defective sensor unit,
disconnected connector,
or damaged sensor wire.

If there is a possibilityof a defective sensor ordamaged sensor wire,
contact New Cosmos
or its authorized
representative.

Page14
Wiring/Connection

Product is inmaintenance mode.

Set the product to gas
monitoring mode.

Page 28
Maintenance Mode

Product is inmaintenance mode.

Set the product to gas
monitoring mode.

Page 28
Maintenance Mode

Incorrect wiring

Check and rewire

Page14
Wiring/Connection

Incorrect alarm point
setting.

Check the alarm
setting.

Page 32
Full-scale andAlarm Set Values
Display

Product is in test mode.

Set the product to gas
monitoring mode.

Page 33
Test ModeGas concentration
exceeds the full scalevalue. Check theambient environment.

Value andflashing alternately.

areSensor output is too
high.

Value andflashing alternately.

areSensor output is too low.

Cannot make or adjust
setting.

Reference pagePage14
Wiring/Connection

Product is in warm-up
cycle.

36

Perform zeroadjustment in clean air.

Page 29
Zero Adjustment

Operate the productafter the 30-second
warm-up cycle iscompleted.

Page 18
Display at Power-up(Warm-up)

Problem

Product does not respondto a HART command sentfrom host system.

Probable cause

Steps

Incorrect wiring

Check and rewire.

Cable used is not a
twisted pair cable.

Use twisted pair cable.

Load resistance is toohigh or too low.

Set the load resistanceof the signal line,
including the resistanceof the wire, to between
120 and 500 ohm,
inclusive.

Noise is present in thelines.

Remove noise from thepower and signal lines.

Line length is too long.

Keep the line length
within 1 km.

Mode is set between 21
to 23.

Change the mode to thegas monitoring modewith magnetic stick.

Combination of items
above.

Clear faults one by one,then restart thecommunication.

Product is in test mode.

Cancel the test mode byoperating the productwith magnetic stick or byhost system.

PV does not change.
Note: Primary Variable(PV) is the first or only
analog channel supported
by a field device.

37

Reference pagePage14
Wiring/Connection

Specifications
Model
Detection principle

KD-12 (Type: HART)

Sampling method

Diffusion type

Target gas

As per delivery specifications.

Detection range
Gas concentration
display
Alarm set value

As per delivery specifications.
Four-digit seven-segment LED display

Alarm accuracy

 Combustible gas: 25% of alarm set value under identical conditions.
 Toxic gas: 30% of alarm set value under identical conditions.

Alarm delay

 Combustible gas: Less than 30 seconds with a gas concentration that is 1.6
times higher than the alarm set concentration.
 Toxic gas: Less than 60 seconds with a gas concentration that is 1.6 times
higher than the alarm set concentration.

Alarms During gas alarm (single stage only), the red ALARM LED blinks.
 During trouble alarm in the event of sensor disconnection, zero drift, power
supply voltage error, internal EEPROM communication error, internal voltage
error, sensor signal amplifier circuit error, gas concentration analog signal error*,or microcomputer error, the amber TROUBLE LED blinks.

External output<Gas concentration analog signal and HART signal>
 4-20 mA DC (common negative with power supply)
 1.6 mA in the event of trouble alarm.
 2.0 mA during the warm-up period.
 Wired HART signal (superimposed over 4-20mA signal), Protocol Rev.7.5
 Load resistance of the analog signal line, including the resistance of the wire, is
not less than 120 ohm and not more than 500 ohm.
<Gas alarm contact (single stage only)> Dry contact. Normally open or normally closed (selectable).
Normally energized or normally non-energized. Automatic resetting.

【KD-12AH】Hot-wiresemiconductor sensor【KD-12BH】Catalytic sensor

As per delivery specifications.

 Max. load: 3.0 A resistive at 250 VAC or 3.0 A resistive at 30 VDC
Equipment or Protective Directive 2014/34/EU
System intended for use SI 2016 No.1107
in Potentially Explosive
Atmospheres
Explosion-proof

Approvals

II 2 G Ex db IIC T5 Gb (ATEX)II 2 G Ex db IIC T5 Gb (UKEx)
Ex db IIC T5 Gb (IECEx)
EU-Type Examination Certificate Number: DEMKO 08 ATEX 143870 X(CE 2776
II 2 G Ex db IIC T5 Gb)
UKEx Examination certificate: CML 21UKEX11353X(UKCA 2503
II 2 G Ex db IIC T5 Gb)
EMC: EN61000-6-4:2007+A1:2011, EN50270:2015 - Type 2
Performance testing: The measuring function of the KD-12 gas detector for
explosion protection in accordance with Annex II clauses 1.5.5, 1.5.6 and 1.5.7 of
the Directive 2014/34/EU, is not covered in this certificate.
IECEx: ULD 13.0001X (Ex db IIC T5 Gb)

Harmonised/Designated EN IEC 60079-0:2018, EN 60079-1:2014
standards
IEC 60079-0:2017 Edition 7.0, IEC 60079-1:2014 Edition 7.0
Degree of protection

IP65 (inside the device)38

Applicable cable

Cable outer diameter: 10 to 14.5 mm
 3-wire twisted pair cable (Power, Analog and HART) with 0.75 to 2.00mm 2 wires.

Operating temperatureand humidity
Power supply Temperature: -10C to 50C Humidity 10% to 90% (at 0 to 50C)
No sudden temperature or humidity changes. No condensation
24 VDC (18 to 30 VDC) (terminal voltage)

Power consumption
Dimensions
WeightMounting method

3 W maximum
128 (W) x 116 (H) x 68 (D) mm (Excluding protruding parts)
Approx. 1.2 kg
Wall mounting- The above specifications are subject to change without notice.
- If your specifications are nonstandard, refer to the delivery specifications.

External markings (for explosion-proof model)

Nameplate detail

Serial number label detail

Rated label detail

Certificate label detail

Warning label detail
Harmonised/Designated standards
EN IEC 60079-0:2018
EN 60079-1:2014
IEC 60079-0:2017 Edition 7.0
IEC 60079-1:2014 Edition 7.0

39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 thewarranty 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.

Life Expectancy of Sensor
The estimated service life of the sensor is shown in the table below. The sensor may fail toprovide correct detection after its service life expires. Replace the sensor before the expiration.
This service life assumes that maintenance is done properly and periodically and that the sensor
is not exposed to high concentration gas or gas that may cause sensor poisoning. This does not
imply that the sensor will provide correct detection values up to the end of the service life. Thus,
no warranty will be given after the one-year period is over.
Model
KD-12 AH
KD-12 BH

Detection Principle(Sensor Type)
Hot-wire semiconductor
Catalytic

Life Expectancy(from the date of purchase)
Approx. 5 years
Approx. 3 years

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

40Detection Principles
Hot-wire Semiconductor Sensor
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
the surface 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 andthus suitable for low concentration gas detection.
Catalytic Sensor
Catalytic combustion occurs on the catalytic layer applied on a platinum coil even if the gas
concentration is well below the lower combustion limit. This causes a rise in temperature of theplatinum 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 (LEL).

Glossary

Term
Gas detector

Definition
Device used to detect the presence of a target gas and to give its
concentration in the form of an electrical signal.

Diffusion type

Sampling method using convective diffusion while placing a gas
detector at a detection point.

Flameproof enclosure(explosion-proof
enclosure)
Target gas

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.

Detection range

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

Operating temperatureand humidity ranges
Maintenance andinspection
Calibration gas(test gas)

Ambient temperature and humidity ranges in which the gas
detection and alarm system can operate normally.
Tasks performed to ensure that equipment operates normally andcorrectly.
Gas specifically prepared to calibrate/adjust the gas detection andalarm system.

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.
41

Term
Explosive atmosphere
LEL

Definition
Mixture of air and flammable substances in the form of dust or vapor
which are within their explosive limits.
Lower Explosive Limit. Lowest concentration (percentage) of a gas
or vapor in air capable of producing a flash fire, or explosion in thepresence of an ignition source like arc, flame or heat.

(Partially quoted from the terms and definitions for gas detector/detector tube by the Industrial Gas
Detectors & Monitors Association of Japan and IEC 60079-0:2017 Edition 7.0.)42

Revision History
Document No.

Date

Revision

GAE-119-00

June 2016(Initial issue)

GAE-119-01

December 2016

01

GAE-119-02

August 201702

GAE-119-03

October 201803

GAE-119-04

January 201904

GAE-119-05

July 201905

GAE-119-06

December 201906

GAE-119-07

April 2021

07

GAE-119-08

September 2022

08

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

Distributor:

Manufacturer:
NEW COSMOS ELECTRIC CO., LTD.
2-5-4 Mitsuya-naka, Yodogawa-ku
Osaka 532-0036, Japan
URL: http://www.newcosmos-global.com