Tork GA 21 User manual

valve & automation
GA 21 Gas Alarm Device
User's Manual
www.smstork.com
PLEASE READ THE INSTRUCTIONS BEFORE USED
JANUARY 2022

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Read the operating instructions first.
INDEX
• Follow the safety instructions.
• These operating instructions are part of the product.
• Retain operating instructions for the life of the product.
• Forward instructions to future users or owners of the product.
Target group:
• This document serves as a guide for personnel using the GA21 Gas Alarm Detector.
It cannot be used as a reference for any other device. The right to make changes is reserved.
Contains information for installation, commissioning and maintenance personnel.
1. Safety instructions .....................................................................................................................................................................
1.1. Security basics............................................................................................................................................................................
1.2. Warnings and precautions...............................................................................................................................................
1.3. Considerations............................................................................................................................................................................
1.4. References and symbols....................................................................................................................................................
2. Identity...................................................................................................................................................................................................
2.1. Description of the device.....……………..............................................…………………...………………………….…..…….
2.2. Intended use of the device………………………….…………………...……..........................…………………..............….….
2.3. Reasons for use.............................………………………………..………………………………….........................………..…...…..
2.4. General view....................……………………………………………………………………………….........................………..…..…...
2.4.1. Relay type electronic board.........………………………………….........................…………..…............
2.4.2. Relayless type electronic board...…………………….........................……..............……..…...........
2.5. Label Information.…………………………………………………………………………………..........................…….......……..…
2.6. Technicial Specifications...............................................………………………………........................…………................…
2.7. Technical dimensions...................……………………………………………………….............................…………................…
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3. Transport, Storage, Packaging, Warranty and Protection measures......................................
3.1. Transport...………………………………………………………………………………………..........……………………………….....….…
3.2. Storage..........……………………………………………………………………………………………………………......…………...…...….
3.3. Packaging..............……………………………………………………………………………………………………………………...…......
3.4. Warranty conditions.......…………………………………………………………………………………………..............................
3.5. Protection measures.......…………………………………………………………………………………………..............................
4. Control Parameters...................................................................................................................................................................
4.1. Possible malfunctions and solutions..................……………………......................…………........….…………..….....
4.2. Power cut……………...............……………………………………………….......................……......................................................
4.3. Making the Settings……………………………………………………………..........……............................................................
4.4. Installation/Assembly..........……….....………….................………………..…..…................................................................
5. Electrical Connections............................................................................................................................................................
5.1. Connection of GA21 gas alarm detector to GAP30 gas alarm control panel.........................
5.2. Connection of GA21 gas alarm detector to another gas alarm control panel...........…....….
5.3. Multiple connection diagram of GA21 gas alarm detectors...................................................…….......

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1. Safety instructions .....................................................................................................................................................................
1.1. Security basics............................................................................................................................................................................
1.2. Warnings and precautions...............................................................................................................................................
1.3. Considerations............................................................................................................................................................................
1.4. References and symbols....................................................................................................................................................
2. Identity...................................................................................................................................................................................................
2.1. Description of the device.....……………..............................................…………………...………………………….…..…….
2.2. Intended use of the device………………………….…………………...……..........................…………………..............….….
2.3. Reasons for use.............................………………………………..………………………………….........................………..…...…..
2.4. General view....................……………………………………………………………………………….........................………..…..…...
2.4.1. Relay type electronic board.........………………………………….........................…………..…............
2.4.2. Relayless type electronic board...…………………….........................……..............……..…...........
2.5. Label Information.…………………………………………………………………………………..........................…….......……..…
2.6. Technicial Specifications...............................................………………………………........................…………................…
2.7. Technical dimensions...................……………………………………………………….............................…………................…
3. Transport, Storage, Packaging, Warranty and Protection measures......................................
3.1. Transport...………………………………………………………………………………………..........……………………………….....….…
3.2. Storage..........……………………………………………………………………………………………………………......…………...…...….
3.3. Packaging..............……………………………………………………………………………………………………………………...…......
3.4. Warranty conditions.......…………………………………………………………………………………………..............................
3.5. Protection measures.......…………………………………………………………………………………………..............................
4. Control Parameters...................................................................................................................................................................
4.1. Possible malfunctions and solutions..................……………………......................…………........….…………..….....
4.2. Power cut……………...............……………………………………………….......................……......................................................
4.3. Making the Settings……………………………………………………………..........……............................................................
4.4. Installation/Assembly..........……….....………….................………………..…..…................................................................
5. Electrical Connections............................................................................................................................................................
5.1. Connection of GA21 gas alarm detector to GAP30 gas alarm control panel.........................
5.2. Connection of GA21 gas alarm detector to another gas alarm control panel...........…....….
5.3. Multiple connection diagram of GA21 gas alarm detectors...................................................…….......
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1. SAFETY INSTRUCTIONS
1.1. Security basics
1.2. Warnings and precautions
The following warnings draw particular attention to safety-related procedures on these devices.
• Our products are designed and manufactured in accordance with accepted standards.
• End user and contractor; must comply with requirements such as legal requirements, directives, installation
guidelines, regulations and recommendations, electrical connection, commissioning, operation and installation.
• All personnel working with this device must comply with the safety and warnings specified in the safety
instructions in order to prevent personal injury and damage to the product.
• Installation, electrical connection, commissioning, operation and maintenance must be performed by
suitably qualified personnel authorized by the end user or contractor.
• Personnel must fully read and understand the instructions before working on this product.
• These instructions are given to know and abide by the officially recognized rules.
• Before commissioning, make sure that all settings are correct.
• Incorrect settings or connections may pose a hazard to the application or damage the installation.
• The manufacturer cannot be held responsible for any consequential damages. This risk is entirely with the user.
• Care should be taken in cases such as transportation, proper storage, assembly and installation.
• Operate the device in accordance with the instructions.
• The end user or contractor is responsible for implementing the necessary protective measures, providing
and supplying guards, barriers or personal protective safety equipment for personnel.
• Maintenance and service operations should only be performed by trained and authorized personnel.
• During maintenance intervention on the faulty unit, it must be worked in accordance with the operating instructions.
• Any device changes require the manufacturer's prior written approval.
Indicates an
imminent
dangerous
situation with a
high level of risk.
Ignoring this
warning will
result in death
or serious injury
Indicates a
potentially
hazardous
situation with
moderate risk.
Ignoring this
warning could
result in death
or serious injury.
Indicates a
potentially
dangerous
situation with a
low level of risk. It
may cause
property damage,
minor or moderate
injury. This warning
should be heeded.
Potentially
dangerous
situation.
Ignoring this
warning does
not apply to
property
damage and
personal injury.
NOTE
DANGER
WARNING CAUTION

CAUTION
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WARNING
1.3. Considerations
• The device should not be used for any other purpose.
• Maintenance and service operations should only be performed by trained and authorized personnel.
• The device must be protected from vibrations and mechanical shocks.
• The frequency and voltage of the power line should comply with the device specifications, and it should
be able to deliver sufficient current to the device.
• Devices that may cause noise should not be placed in the supply line.
• The device should not be constructed in such a way that the device's power cables, sensor cables,
output connection cables, and the gas alarm device and cables to which it is connected may prevent the
movements of persons.
• The device must be used with accessories and parts supplied by the manufacturer. The use of different
accessories and parts may cause the device to malfunction or malfunction.
• The device and its cables should not be subjected to any mechanical stress.
• The device and its accessories should be checked at least once a year.
• If possible, a fire extinguisher should be available.
• The user must have received the necessary training and knowledge about fire extinguishing.
• After making sure that the device connections are made correctly and completely, the device should be
started.
Pay attention to the following points in order to use the device safely.
• First of all, stay calm.
• Heed and obey the warnings, alarms and messages specified in this instruction and the device.
• The device shuts down the energy of the relevant system connected to the output relay, in case of any
malfunction, inability to detect leakage gases, or in case of alarms due to different reasons.
• Check if there is a gas leak in the environment where gas alarm detectors are located. If there is, open the
doors and windows without panic, and let it ventilate.
Against the risk of fire;
• Close the gas valve, starting from the place closest to you.
• Do not plug any electrical appliances into sockets.
• Do not use electrical devices. Warn users.
• Do not use devices such as doorbells, cell phones and walkie-talkies.
• Contact a specialist from the gas distribution company in a suitable safe place.
If the device gives an alarm in cases such as gas leakage detection or malfunction due to
possible reasons, the following points should be paid attention to in environments where
gas leakage occurs.

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• If there is a flame, put it out. If there is a natural gas sourced flame, it is useless and dangerous to try to
extinguish the flame without closing the gas valve. If the flame size is large, immediately inform service
units such as fire extinguishing, fire brigade and take action.
• If electrical equipment is on fire, do not try to extinguish it with water. Use a fire extinguisher.
• If you smell gas before the device alarms, intervene appropriately by following the warnings and
instructions without waiting for the device to alarm.
• If the cause of the alarm cannot be found even though the gas leak continues, leave the area for
precaution. Contact the gas distribution company to check the parts, make them safe and make the
necessary maintenance and repairs. If there is a device problem, inform the manufacturer.
• Check all accessories and connections before using the device. Do not use damaged accessories and
cables. Improper accessories, faulty or poor connections can cause unexpected potential problems such
as electrical shocks.
• Before commissioning the device, make the necessary settings on the device, make sure that it detects
gas, that the output control relays work, that the buzzer (audible warning) and signal output work.
• When the device needs to be tested with gas, first check if there are gas leaks or situations that may
cause danger in the environment. If there is a danger, cut the power of the device and take it to a safe
environment and perform the test procedures there.
• During installation/assembly and commissioning, the user must use appropriate assembly tools and
avoid any actions that may endanger his own safety.
MARKINGS/SYMBOLS DESCRIPTIONS
+24V
+12V
+5V
+V
-V
+S
GND
VIN
S1
COM
NO
NC
Grounding Symbol
+24V port on DC voltage supplies
+12V port on DC voltage supplies
+5V port on DC voltage supplies
DC voltage supply + voltage port
DC voltage supply - voltage port
Analog signal output port
0V port on DC voltage supplies
AC or DC voltage supply port
Analog signal output port
Relay outputs port common contact terminal
Relay outputs port common contact terminal
Relay outputs port common contact terminal
The port where the grounding connection of the device will be made
The following references and symbols are used in this instruction and on the electronic
boards.
1.4. References and symbols
Table 1:Symbols

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2. Identity
The GA21 gas alarm detector is a device that detects explosive gases in the environment. 1.5 minutes
after the supply voltage is applied, the sensor warms up and reaches the normal detection level. It is not
recommended to test with any gas before this period expires. If the gas leakage level is above the set
limit value, the device gives an alarm. As long as the gas leakage is above the limit level, the device
continues to alarm. When the gas leakage falls below the set limit level, it automatically shuts down the
alarm and relays and cuts off the energy of the connected systems.
If the gas valve is to be closed or the gas to be evacuated from the environment under alarm conditions,
the desired system can be controlled by using the output relays of the gas alarm device. Analog output
signals in the device PLC etc. It can be controlled by connecting to systems such as By changing the
sensor head, different gases can be detected. It is a general-purpose, simple and easy-to-use device that
can output mA or volts, control the systems connected to the output relays, and give audible and visual
warnings.
Developed considering the needs of the user, the GA21 gas alarm detector has a structure that simplifies
and strengthens the communication between the user and the device. The device contains 2 output
control relays, 1 gas level output (mA and Volt), 1 buzzer (audio warning), Zero, Span and offset (%LEL
adjustment) trimpots and electronic board.
2.1. Description of the device
GA21 gas alarm detector is connected to the level signal output and connected to intelligent and
controllable systems (PLC etc.) (0-20, 4-20, 0-10, 2-10 mA, 0-5, 1-5, 0-10, 2 -10 VDC) sends analog
signals. It is a product that aims to warn the user with sound and light by controlling the gas level in the
environment, to send signals to the connected systems, to control, to use the systems it controls safely
and to prevent possible dangers.
2.2. Intended use of the device
• Long life
• Being ExProof
• Less energy consumption
• Modular design structure
• Easy assembly and disassembly
• Ease of adjustment and flexible operation
• Robust and lightweight construction
• Informing the user with the alarm
2.3. Reasons for use

Figure 1. General View of the Device
Figure 2: Relay Type
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2.4. General View
The figure given below is given to inform the user about the structure of the device. It is produced in two
according to their features. is that there is no relay and buzzer in the non-relay type. The electrical-electron-
ic and mechanical components of the GA21 gas alarm device are given in Figure 1, Figure 2 and Figure 3.
DEFINITIONS
DEFINITIONS
Body
Electronic Card
Cover
Cover Opening Place
ExProof Icon
Cover Fixing Screw
Label Fixing Screw
Label
Sensor Housing Cover
Sintered Filter(IP55)
Sensor
Sensor Housing Connector
Body Fixing Leg
Stopper
Ground Screw
Cable Entry Connector
Electronic Card Fixing Screw
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
The electronic card image of the GA21 series gas alarm detectors with relay is given in the figure below.
Here, the electronic card structure and electrical-electronic components are defined. It is recommended
that the user be familiar with these components and technical specifications. (See 2.6. Technical
specifications Table 3) When valves, sirens or other systems are connected to the relay contacts, the
current value that can pass through the contacts must be taken into account. In case of connecting systems
that draw excessive current, it may cause unexpected possible malfunctions in the relay or components on
the electronic board. At the same time, Low level adjustment can be made with ZERO trimpot and High
level adjustment can be made with SPAN trimpot. Alarm trimpot is also used to determine the alarm level of
the device. According to the gas density in the environment, it can be monitored with the analog signals
produced by the devices or it can control the systems it is connected to. When the output signals reach the
alarm level, it gives an audible alarm with a buzzer.
2.4.1. Relay type electronic board
Signal Output
Supply Voltage
Supply Voltage
Relay Contact (NC)
Relay Contact (COM)
Relay Contact (NO)
Alarm Level Adjustment Trimpot
Buzzer
Sensor Socket
Fixing Holes
Span Trimpot
Zero Trimpot
Output Signal Selection Table
Signal Selection Switch 1
Signal Selection Switch 2
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
In the picture below, the components of the relayless type GA21 gas alarm device electronic card are
given and defined according to their functions. It can give more than one different output control signal.
The user can adjust the low and high sensitivity settings with the zero and span trimpots, and the output
control signal can be selected from Table 2 with the signal selection switches.
2.4.2. Non-relay type electronic board
4
12
3
6
7
8
9
10
11
12
13
14
15
16
17
5
123456
7
8
9
10
11
12
13
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Body protection class
Body material
Dimension
Weight
Supply voltage
Gas detector supply voltage
Tank level sensor supply voltage
Power consumption
Output control relat
Output control relays maximum
current carrying capacity
Gas level detect input
Tank level detect input
Gas level input control signals
Gas level input control signals
Environment temperature
Sound intensity
Alarm
Relative humidity
Language
User interface
: IP54
: ABS
: 72x144x115mm
: 515 gr
: 24VDC
: 12VDC
: 12VDC, 5VDC
: 1.5W
: Gas control relays(2 Number),
siren relay, Tank1 relays(AL and UL),
Tank2 relays (AL and UL)
28VDC 10A, 250V AC 7A
8 number
2 number
0/4-20 mA, 0/2-10 mA, 0/2-10V DC, 0/1-5V DC
0/4-20 mA, 0/2-10 mA, 0/2-10V DC, 0/1-5V DC
-10°C ~ +50 °C
85dB
Audible, light and can be viewed on the screen
30 ~ 75 %
Turkish-English(blue-white),
Keys and warning leds
TECHNICAL FEATURES
123
4
5
6
7
8
DEFINITIONS
Signal Selection Switch
Signal Selection Switch
Signal and Supply Voltage Terminal
Sensor Socket
Electronic Card Fixing Hole
Zero Trimpot
Span Trimpot
Signal Selection Table
1
2
3
4
5
6
7
8
Figure 3: Non-relay Type
Table 2: Signal Selecction Table
S1 S2 Output Signal
ON
ON
OFF
OFF
ON
OFF
ON
OFF
1-5 Volt
2-10 mA
2-10 Volt
4-20 mA
2.7. Technical Dimensions
2.6. Technical Features
2.5. Label Information
168
120
130
100,70
115,65
Figure 4: Output Connection Terminals
Figure 5: Technical Dimensions
Table 3: Technical Features
70 mm
30 mm
65 mm
R 2,5
EXPLOSION-PROOF GAS ALARM DEVICE
II 2G Ex mb db IIA T4 Gb IEP 14 ATEX 0224
SIZE:B/NPT 1/2
MIN-MAX TEMPERATURE:
IP 65
TYPE: GA 21 V:12-32 V AC/DC

CAUTION
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Şekil 5. Elektrikli Aktüatörün Vanaya Montajı
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• Check the packaging.
• Observe the signs and symbols on the packaging.
• Make sure that the signs and symbols on the packaging are visible.
A dangerous situation due to improper transport.
Our products are protected by special packaging for transportation when leaving the factory.
The packaging materials used in packaging consists of environmentally friendly materials that
can be easily cleaned. It should be separated and recycled. Packaging materials such as wood,
cardboard, paper, PE foil are used. TORK recommends recycling and collection centers for the
disposal of packaging materials.
3.3. Packaging
• The warranty period starts from the delivery date of the product and the warranty period is 2 years.
• The entire product, including all its parts (against failures that may arise from our production and
assembly errors and/or defective parts), is within the scope of our company's warranty.
• If the product fails within the scope of warranty;
3.4. Warranty
During the transportation of the GA21 gas alarm device, consider all kinds of variable
transportation conditions such as impact, vibration, falling, rain, transportation that may
damage it. Pack it well so that it reaches the installation site securely.
• Store in a well-ventilated dry place (maximum humidity 75%).
• Protect against dust and dirt.
• Protect against ground moisture by storing on a shelf or on a wooden pallet.
• Protect against excessive temperature, humidity and water.
• Keep away from harmful oscillations such as magnetic field, radiation.
Risk of corrosion and deterioration due to improper storage.
3.Transport, Storage, Packaging, Warranty and Protection measures
3.1. Transport
3.2. Storage
NOTE

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The time spent in repair is added to the warranty period. The repair period of the product is maximum 20
business days.
• The warranty starts from the date of notification of the product defect to the TORK authorized service,
or in the absence of an authorized service station, to the seller, dealer, agency, representative, importer or
manufacturer of the product. The consumer can make the failure notification via telephone, fax, e-mail,
registered letter with return receipt or similar, but in case of conflict, the burden of proof rests with the
consumer.
• The product;
• In the event that it breaks down at least four times within a year or six times within the warranty period
determined by the manufacturer and/or importer, provided that it remains within the warranty period, from
the date it is delivered to the consumer, and if the user is not able to benefit from this product due to these
faults,
• In case of exceeding the maximum time required for repair,
• If it is determined that the repair of the malfunction is not possible with a report prepared by the seller,
dealer, agency, representative or one of our company's officials, respectively, if the service station is not
available, the product will be replaced free of charge.
• The warranty period of the product that has been changed during the warranty period, the purchased
product, TORK Industrial Automation Products San. Trade Ltd. St. limited to the remaining warranty period
provided by
• Free repair and product replacement obligations are eliminated in the following cases.
• Failure of the product due to use contrary to the methods or conditions specified in the user manual,
• The product and the warranty labels on its contents are damaged/torn,
• If it is determined or noticed that the product has been opened/repaired before, other than TORK
Authorized Service personnel,
• In case the outer surfaces of the product and its components are broken within the customer's
responsibility,
• Incorrect handling (bump, drop, impact), inadequate maintenance, abuse, use contrary to the
environmental characteristics specified in the user manual, use of the product in excessively humid, dusty
or hot environments, use in environments that are damaging to electronic circuits and corrosive, failures
caused by accidents, impacts, electricity (voltage changes), natural disasters,
• Malfunctions or damages during transportation that are not under the responsibility of SMS Sanayi
Malzemeleri Üretim ve Satası A.S.,
• In case the defective part is replaced with parts other than TORK Authorized technical services and/or
parts without SMSTORK warranty
• If it is determined by a report to be issued by the TORK authorized service, whether the malfunctions
occur as a result of usage error or not.

Types of Failure Corrective Interventions
The device does not turn on
Device gives alarm continuously
Device does not output signal
OFFSET setting cannot be made
Unable to set Zero and Span
The device works but does
not give any alarms
Disconnect the supply voltage cable from the mains. Check if there is electricity
coming from the cable with the help of a measuring instrument. Check the
power supply. If problematic, replace cable or power supply. If the problem
persists, inform the company by taking the necessary measures.
Check the electronic board, the cables to which the output signal is connected,
the sensor and the terminal connections. Gas detection sensor or electronic
board may be broken. If the problem persists, contact the manufacturer.
The OFFSET trimpot of the device may not be adjusted properly. Adjust with
the OFFSET Trimpot. The sensor may be broken. Replace with new one.
Check the OFFSET trimpot. It may be corrupted. Solve the problem by
contacting the manufacturer.
Check the Zero or Span trimpots. It may be corrupted. Solve the problem by
contacting the manufacturer.
Check the electronic board, the cables to which the output signal is connected,
and the terminal points. Gas detection sensor or electronic board may be
broken. If the problem persists, contact the manufacturer.
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Before connecting and commissioning the GA21 gas alarm device, the user should have information
about the device in hand. The table below gives information about corrective actions when a
problem occurs with the device.
Before each use of the device, take precautions against damage such as rupture, crushing,
cracking in the connections, that the device connections are in accordance with the instructions
for use, electrical leakages, liquid leaks and accumulations.
3.5. Protection measures
4. Control Parameters
4.1. Possible malfunctions and solutions
If there is a voltage fluctuation in the mains line, regulate the voltage
fluctuation so that the device can measure correctly. Safety principles should
NOT
• If the device fails after the warranty period, if you have a service agreement with TORK, request the type
of service available in this agreement. If you do not have a service agreement, you can get service by
contacting the TORK dealer or customer service center.
• Use original packaging materials whenever possible. The responsibility of the damages that may occur
during shipment due to improper packaging belongs to the customer.
• Regarding the Warranty Certificate; For problems that may arise, an application can be made to the
Ministry of Customs and Trade, General Directorate of Consumer Protection and Market Surveillance.
never be compromised as the gas industry is in a dangerous industrial sector group.
Table 4: Possible malfunctions and solutions

NOTE
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GA21 gas alarm devices are offered to the user in the form of relay and non-relay types.
Offset, Zero, Span settings are adjusted with the trimpots on the electronic board, and output
signal selection can be made with the sliding switches.
OFFSET Trimpot; It is the alarm level adjustment trimpot. With this trimpot, the user can set the
alarm limit level of the device in %LEL.
SPAN Trimpot; It is used to adjust the upper limit level of the 4-20 mA signal when needed.
ZERO Trimpot; It is used to set the lower limit level of the 4-20 mA signal.
SLIDING Switches; It is used to select the output signal and the type of output signal as mA or
voltage.
When the power is cut off, the device will turn off. Since similar systems such
as the gas shut-off valve connected to the device output will close it, it will
stop the gas passage. When the power comes on, the device will turn on and the device will
continue to work normally. The user must activate the closed valve and similar mechanical
systems.
4.2. Power cut
4.3. Making the settings
• Make sure the device is intact before performing the Device Setup.
• Review the cables and ports for the device.
• Do not mount in a way that narrows the user's work area.
• In case of emergency, install it in such a way that it is easily accessible and easy to intervene.
• The lower explosion limit of % lel (APS) differs according to the type of gas used. Have a measuring
device available.
• Set the alarm level of the device with the OFFSET Trimpot.
• Identify areas that may pose a hazard as a result of gas leakage.
• Determine the places where the device will be mounted.
• Follow the instructions when performing the Installation/Assembly process.
4.4. Installation/Assembly

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The connection diagram below shows the connection of the GA21 gas alarm detector to the GAP30
gas alarm control panel, as an example.
5. Electrical Connections
5.1. Connection of GA21 gas alarm detector to GAP30 gas alarm control panel
• Power supply is connected to pins 1 and 2 of GAP30 gas alarm panel.
• Two GA21 gas alarm detectors are connected. The supply voltage of one of the GA21 gas alarm detectors
is taken from pins 11,12, and the signal cable is connected to pin 15. The supply voltage of the other GA21 gas
alarm detector is taken from pins 17,18, and the signal cable is connected to pin 25.
Figure 6: Connection of GA21 Gas Alarm
Detector to GAP30 gas alarm panel
GA21
GA21
+24V
GND
DEVICE SUPPLY
VOLTAGE
+V(12VDC)
+S(4-20mA Control Signal)
GND(DC)
L (PHASE)
N (NEUTRAL)
E (EARTHING)
+V(24V DC)
VALVE2 VALVE1
(L),(+V)
EXTERNAL VOLTAGE INPUT(max.5A)
(N),(GND)
E (EARTHING)
GAP30 GAS ALARM PANEL
SIREN RELAY2 RELAY1
SIREN

NOTE
Figure 8:
Multi-connection of
GA21 gas alarm detectors
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15
Figure 7: Connection of GA21 Gas Alarm Detector
to another gas alarm panel
Relay outputs of GA21 gas alarm detectors have a dry contact structure. It needs
external voltage from outside. E.g; If the system to be controlled (valve siren etc.)
will operate with 230VAC voltage, the user must pass 230V AC voltage through the relay contacts.
5.2. Connection of GA21 gas alarm detector to another gas alarm control panel
AC or DC voltage can be supplied to the VIN inputs of GA21 gas alarm detectors. The power supply used
must be at a level that can meet the sufficient voltage and current requirements of the detectors. When
the device is operated with an AC voltage output power supply, do not short-circuit the GND pin on the
signal output to the VIN pin or bridge it. Connect the GND and +S terminals directly to your system.
When the device is operated with a DC voltage output power supply, the GND pin on the signal outputs
must be connected or bridged to the V terminal of the supply voltage from inside the device.
5.3. Multiple connection diagram of GA21 gas alarm detectors
DEFINITIONS
VIN(Supply Voltage WC or DC) Pin
VIN(Supply Voltage WC or DC) Pin
Signal Output (GND) Pin
Signal Output(+IOUT) Pin
1
2
3
4
1
2
3
4
4-20mA
GND
SIGNAL OUTPUT
4-20mA
GND
SIGNAL OUTPUT
4-20mA
GND
SIGNAL OUTPUT
+24V
GND
DEVICE SUPPLY VOLTAGE
+S(4-20mA Control Signal)
GND(DC)
+V(24 DC)
GND(DC)
+S(4-20mA Control Signal)
GND(DC)
+V(24 DC)
GND(DC)
GA 21 NON-RELAY TYPE CONNECTION SCHEMA GA21-ROLELİ TİP BAĞLANTI ŞEMASI
+24V
GND
DEVICE SUPPLY VOLTAGE
4-20mA
GND
SIGNAL OUTPUT
NO
COM
NC
RELAY OUTPUT
NO
COM
NC
RELAY OUTPUT
NO
COM
NC
RELAY OUTPUT
4-20mA
GND
SIGNAL OUTPUT
4-20mA
GND
SIGNAL OUTPUT

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NOTE

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KUL.TREA0150 /31.01.2022/Rev.01 TR
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KUL.GA21 /06.07.2022/Rev.04en
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