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Company address:3/floor production cencer No.58 industrial second road, national.civil aerospace industry base,  Xi'an, Shaanxi province.
Postcode: 710100
Contact phone: 86-029-88452932
Mobile telephone:18092305062
Fax number: 86-029-88454310

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Point type temperature detector

Date of release:(2019-1-24)   Click times:170


Model JTW-A2-992004

Point-type Thermal Fire Detector



Please read these introductions carefully before the installation so as to use the detector properly.

The JTW-A2-AHG992004 point-type thermal fire detector (detector for short in the followings) is developed from the temperature sensitivity of the thermal component. The detector is produced using the SMT process, with stable and reliable performance, and strong resistance to heat, it applies to hotels, restaurants, office buildings, teaching buildings, banks, warehouses, libraries, computer rooms and power distribution room, etc. It must be used together with the controllers compatible with our company.

First: Features

2 Distributed intelligence, and it has quasi-16 microprocessor and internal data storage built-in.

2 Unique bar code for identification with no coding switches and manual settings such as electronic addressing required.

2 Digital signal working mode and superior anti-electromagnetic interference capability.

2 With modern multi-fire criterion algorithm, self-identify the authenticity of the fire alarm, and so the system reliability and speed of response are improved.

2 Making an automatic test on its operation through its perfect self-diagnostic function.

2 Making automatic compensation for the changes of the environment (non-fire factors such as dust, temperature and humidity etc) through its comprehensive self-learning and self-adaptive function.

2 Double light-emitting diodes display in 360-degree. It can either do alarm display or do detector state tests.

Second: Technology characteristics

1. Operating voltage: Signal bus voltage: Bus 19VDC

Allowable range: 16VDC ~ 22VDC

2. Operating current: Monitoring current: +60μA.

Alarm current: +460μA

3. Alarm confirmation lights: Red, Normally on when alarm

4. Encoding: Automatically identify bar code by control plane software, without manually writing code

5. Wire: Signal 2 bus

6. Protecting area: The protecting area of one detector is 20~30 square meters for general sites when the space height is below 8 meters. Specific parameters should be subject to "automatic fire alarm system design" (GB 50116-98)

7. Ambient:

Temperature: -10≧+50≧

Relative humidity: + 95%, no condensation

8. Dimensions: diameter: 104mm    high: 65mm (without base)

9. Installation accessories: DZ-BZ-AHG2025 type standard base / DZ-GL-AHG2026 type isolation base

10. IP grade: IP32

11. Crust material and color: ABS plastic, Matt White

12. Weight: About 110g

13. Installation Pitch: 45mm ~ 60mm

14. Executive Standard: GB 4716-2005

Third: Structure character and working principle:

1. Detector schematic form is shown in Figure 1.

Figure 1 Schematic diagram of detector shape

2. Working principle:

The detector uses the thermal component as the sensor whose output signal is sent into the SCM after AD transformation, and the SCM makes a judge through the built-in fire module. When the SCM detects a fire signal, it sends fire alarming information to the controller and lights the fire alarm light through the controller.

Forth: Installation and wiring

Notice: All wiring must comply with relevant laws and regulations.

Confirm that the base has been installed solidly and the cable polarity is correct.

Prohibit the application of any paint on the base, or the detector performances will be affected.

Warning: Cut off the power supply before installing the detector.

1. Installation:

The detector must be used together with the base produced by our company. The base can be fixed inside the embedding box or on the plane directly. The detector installation diagram is shown in Figure 2

a. Wiring in accordance with the detector base given in Table 1.

b. Confirm the detector type is of the same type as noted on the design drawings.

c. Put the detector on the base, then push it in the direction of the base, and rotate the detector clockwise until it is rotated into the base. The detector base form is shown in Figure 3.

d. It will be ok as soon as the detector has been rotated to the end.

Figure 2 Schematic diagram of detector installation

Figure 3 Schematic diagram of detector base shape

Common Pin



Power +, connect loop A +, B +


Signal in, connect loop A-


Signal out, connect loop B-

Special Pin



Earth (use under special occasions, such shielding required)


Signal in, connect loop A-(connect with isolator base )


Can connect with remote indicator door lamp


Signal out, connect loop A-(connect with isolator base )

Table 1 shows the base terminal

2. Wiring

For detector 2 bus it is appropriate to use the AVS twisted-pair whose cross-sectional area is greater than or equal to 1.0mm2, laying through mental pipe or fire-retardant pipe. The total resistance of the bus loop wire should be less than 50Ω, and the total capacitance should be smaller than 0.3μF. The total length of the loop wire should not be longer than 2000m.

Figure 4 loop wiring method (992025 as the standard base, 992026 as the base with isolator)

3. Figure 4 indicates the wiring methods of the AHG2000 series fire detector when connected into a loop. For the wiring methods of the AHG2000 series intelligent detector with branches, please refer to < AHG9600 manual fire alarm controller design manual>.


1. Prohibit branches access to the root of the loop.

2. Make sure that all the unused terminal screws tightened after the base installation.

3. Make sure the connection between the down-lead and the terminal compact and reliable before installing the detector into the base.

Fifth. Testing

Note: Remove the dust cover when taking the first test and install the dust cover before normal running to prevent dirt from entering.

Warning: Don't put the power through before installations of all units are finished.

1. The detector must be tested after the installation and the regular maintenance.

2. Testing content:

Topology recognition: After affirming the validity of the installation and the wiring, recognize the detector automatically through the controller connected, and check the number of detectors installed and the circle structure according to the design drawings.

Simulative fire: After the topology recognition, choose one detector with man-made satisfied fire conditions to verify whether the detector reports a fire normally.

3. When the test is done, there come communication commands through the controller to reset the detector, and inform the relevant managing department that the system is back to normal again.

4. During the test, deal with the unqualified detectors according to the "Common faults and maintenance" and "Maintenance", and then give them a second test. If they are not satisfied still, return them back to the factory for maintenance.

Sixth. Use and operation

Built-in bar code before leaving factory to greatly lower the constructing difficulty and shorten the project time needed due to none manual coding. Do the following operations as the installation is finished:

1. Topology recognition: There comes a topological recognition command from the controller to read the address of the detector automatically so as to certain the loop structure.

2. Simulative fire: After the topology recognition, pick an optional ring circuit detector unit to select analog flash commands, and the corresponding detector alarm lights should be normally on indicating that the detector is working properly.

Seventh. Common malfunction and maintenance

When there is a fault, make a check that whether the outer connecting is right, and if it is, then open the case and observe the circuitry board to find such abnormal phenomena as false weld, burn and so on.

The possible faults and their maintenance approaches are concluded as following:

1. Cannot catch the host computer (the common phenomenon is that the detector reports missing): Please check as the following steps:

Check whether the connection between the detector and the host computer is correct and reliable; please replace the base if the detector base spring is oxidized or out of shape. The right connection between the detector and the host computer is shown in Figure 4

2. Can not alarm:

Check whether the detector thermostat is in good condition.

3. Annex failure or no annex (base isolators) identification

Check whether the detector terminal contacts well with the base spring. Please replace the base if the detector base spring is oxidized or out of shape. And replace the base isolator or base relay if necessary.

Warning: If the detectors cannot work normally after the maintenance above, return them back to the factory, please.

Eighth. Maintenance

1. The detector must be installed just before it is going to have a debug, and it must be kept properly with corresponding dust, moisture, and anti-corrosion measures before the installation.

2. Take off the dust cover only after the project has been put into use formally or there will be a false alarm.

3. Clean the detector more than once a year to make sure the system is running normally.

4. Take a simulated fire alarm every six months to test detector.

5. Before the cleaning and test, the relevant managing department must be informed that the system is going to have maintenance and so there may be a temporary cessation of work as a result. Cut off the logical control function of the area or system at the same time so as to avoid unnecessary alarm linkage.

Ninth. Notes

1. Take off the dust cover only after the project has been put into use formally or there will be a false alarm.

2. The dust cover can prevent dust entering detector effectively, but not completely stop the dust particles swimming in the air into the detector. So, the suggestion is, take off the detector before carrying out civil construction, renovation or other activities which can produce dust. But the relevant authorities must be informed.

3. 0.5m around the detector, there should not be blocked matters.

4. The level distance from the detectors to air conditioning hole should not be less than 1.5m.

5. The level distance from the detectors to wall, beam edge should not be less than 1.5m.

6. It is appropriate to install the detector level. If the detector must be tilted, the tilt angle should not exceed 45<.

7. The detector base should be installed firmly and the wire connections must be reliable.

8. Setting a detector in the inner corridor ceiling with width less than 3m, it is appropriate to center the layout, and installation interval of thermal detector should not exceed 10m.

9. The detector alarm confirmation lights must face the easily observed direction of main entrance.

Tenth. Do not install the smoke detector in the following areas:

1. Possibly produce smoldering fires or other places causing significant losses if the fire is not alarmed early.

2. The temperature below 0≧.

3. Large temperature changes under normal circumstances.


ADDRESS:3/floor,production center,No.58,industrial second road,national.civil aerospace industry base,Xi'an,Shaanxi province

TEL: 029-88452932

FAX: 029-88454310

貧匯鐙Point type smoke detector 和匯鐙Fire alarm controller (combined)
Company address:3/floor production cencer No.58 industrial second road, national.civil aerospace industry base,_ Xi'an, Shaanxi province.
Postcode: 710100
Contact phone: 86-029-88452932
Mobile telephone:18092305062      Fax number: 86-029-88454310
Copyright@2018 Xi'an van lag Electronics Co., Ltd.      Record number: Shaanxi ICP 18008942-1
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