图1

4.3 Installation Precautions for temperature-sensing Cables

1) The temperature-sensing cable should be installed in a location that is not severely compressed and where the sheath is not easily damaged by sharp objects from the outside.

2) The temperature-sensing cable should avoid contact with materials that absorb heat and cause delayed temperature rise in the monitored area. The fixture parts that come into direct contact should be made of non-metallic materials. The damaged part.

3) The minimum bending radius of the temperature-sensing cable is 15mm.

4) When laying temperature-sensing cables with cable straps, rubber sleeves should be used for protection.

The fixed distance between the two support points of the temperature-sensing cable should be within the range of 0.6 to 1.2 meters.



4.4 Installation Precautions for Terminal Boxes and junction Boxes

When installing the terminal box and junction box, the following principles must be followed to ensure that the protection level of each part of the detector is achieved. Otherwise, the reliability of the detector will decline, its performance will be reduced, and false fire alarms or malfunctions may occur.

When terminal boxes and junction boxes are installed indoors, they should be fixed on the walls or metal brackets near the site, at a height of about 1.5 meters above the ground.

After the temperature-sensing cable is wired to the junction box and terminal box, the cable tightening joint should be tightened clockwise to ensure its sealing performance.

3) When loosening or tightening the cable tightening joint, the rubber sealing sleeve inside the cable tightening joint should be placed upright to prevent the protective performance of the box from being reduced due to the detachment or deformation of the rubber sealing sleeve.

4) When installing the outer covers of the terminal box and junction box housing, apply uniform force to tighten the four installation screws on the outer covers to ensure that the sealing rings of the box bodies deform evenly and the sealing is good.

5) Drill holes or install other components on the terminal box and junction box shells; Terminal boxes and junction boxes should be avoided from being installed in extremely damp or water-soaked places.

Terminal 5 Description

5.1 Terminal description of the junction box

Figure 3: Terminal diagram of the junction box



Terminals S and COM: Connect to the signal input terminals of the input module, with S being positive.

2) Terminals SA and SB: Input terminals of the temperature-sensing cable;

3) E: Grounding protection terminal;



5.2 Terminal Box Terminal Description

Figure 4: Terminal box terminal diagram



Terminals SA2 and SB2: Input terminals of the temperature-sensing cable;

2) Terminals SA1 and SB1: Backup module terminal resistor access terminals;



The terminal box provides the following several specifications of terminal resistors. Users can select them through the short-circuit ring according to the requirements of the input module. If there is no suitable terminal resistor, pull out the short-circuit ring and connect the terminal resistor provided with the input module to terminals SA1 and SB1.

The available terminal resistors are: 2.4K, 3.3K, 4.7K, and 10K.



Wiring must be carried out strictly in accordance with the instructions and confirmed to be correct. Otherwise, it will affect the stability of the detector's operation and even cause damage to the detector.



6. System wiring

When used in conjunction with a bus-based fire alarm control system, the alarm signal of the linear temperature detector can be connected to the system through the input (monitoring) module. The wiring method is shown in Figure 4.

图4

5. Operation and maintenance as well as common fault handling

Operation and maintenance

1) Regularly (it is recommended to conduct routine inspections of the appearance of the linear temperature detector and the operation status of the fixture every six months.

2) Regularly select detectors in a certain proportion (it is recommended to select 5% annually) for simulated fire alarm tests. The method is as follows: After the normal inspection of the alarm controller, heat a section of the temperature-sensing cable no less than 1m long, 500mm away from the terminal box, with boiling water (when the alarm temperature is below 90℃) or wax fire. The alarm controller should report a fire alarm signal. After the test is completed, cut off the damaged parts and reconnect the detector. When conducting a fire alarm test, necessary fire safety measures should be taken (Note: During the test, the flame of the candle should be stable and continuously heated evenly).

4) Regularly (it is recommended to do so every two years), use a 500V megohmmeter to check the insulation resistance of the detector (both ends of the temperature-sensing cable must be completely disconnected from the circuit). The insulation resistance value should be greater than 20MΩ. Otherwise, the cause should be identified and the temperature-sensing cable replaced if necessary.



Common Fault handling

When the detector malfunctions, it is usually an open circuit fault. Locate the part of the open circuit and take corresponding measures.

2) When there is a joint in the middle of the detector, a temperature-sensing cable intermediate junction box must be used and the wiring must be installed as required to ensure the stable operation of the detector.

3) For occasional false alarms of fire or false alarms of faults in detectors, records should be kept and the causes should be identified and faults eliminated from the following aspects:

Check whether the sealing of the junction box and terminal box is good.

Check whether the sheath of the temperature-sensing cable is damaged.

Check whether the terminal connections of the junction box and terminal box are firm and reliable.

Check whether the detector is well grounded.

After confirming that all the above checks are problem-free, it is necessary to consider whether the temperature-sensing cable is affected by electromagnetic interference. At this point, contact the input module manufacturer for a solution or use the isolated signal converter produced by our company to solve the problem.