salt spray test chamberThe heating function is the core of maintaining stable test temperature. Once there is no heating, it will directly affect the accuracy of salt spray environment simulation. Starting from common causes, the following Hubei Gaotian experimental equipment provides systematic troubleshooting and solutions.

1、 Power and circuit troubleshooting

1. Check if the power supply is normal

Firstly, confirm whether the power plug of the test box is securely plugged in and whether the socket is powered on (other electrical appliances can be plugged in for testing). If using a three-phase power supply, it is necessary to check whether the corresponding circuit breaker in the distribution box has tripped, and observe whether the power supply has been restored after resetting.

Measure the power supply voltage with a multimeter to ensure that the voltage is within the rated range of the equipment (usually 220V ± 10% or 380V ± 10%). Unstable voltage may cause the heating system to fail to start.

2. Check if the heating circuit is open circuited

Open the side cover of the device, find the connecting wire of the heating tube, and use a multimeter to check the resistance range at both ends of the heating tube. The normal resistance value of a heating tube is generally several tens of ohms (refer to the equipment parameters for details). If it displays infinity, it indicates that the heating tube is blown and needs to be replaced with a heating tube of the same model.

At the same time, check whether the temperature controller output terminal and relay contacts in the heating circuit are conductive. If the contacts are oxidized or stuck, they can be sanded or the relay can be replaced directly.

2、 Troubleshooting of Temperature Control System

1. Is the temperature sensor abnormal

A temperature sensor (such as Pt100) malfunction can cause the thermostat to misjudge the temperature and stop heating. Measure the resistance of the sensor with a multimeter. At room temperature, the resistance of Pt100 is about 100 Ω. As the temperature increases, the resistance increases. If the resistance is abnormal or the circuit is broken, the sensor needs to be replaced and recalibrated.

2. Is the temperature controller setting and operation normal

Check if there are error codes (such as "Err") on the temperature controller display screen, and refer to the equipment manual for the corresponding code meanings (such as sensor failure, over temperature protection).

Confirm whether the set temperature of the thermostat is higher than the current measured temperature (usually set at 35 ℃ for salt spray testing). If the set value is too low, the parameters need to be readjusted; If the thermostat has no output signal, it may be due to internal component damage and the thermostat needs to be replaced.

3、 Handling of other common issues

1. Overtemperature protection device triggered

The test chamber is often equipped with over temperature protection (such as temperature control switches). If the temperature exceeds the set upper limit (usually 40-50 ℃) during the heating process, the protection device will automatically cut off the heating power supply. At this point, it is necessary to press the reset button of the protective device (usually located on the back of the equipment or inside the electrical control box) and check if the temperature control system is out of control.

2. Scaling or poor contact of heating tube

After long-term use, the surface of the heating tube may scale (especially when using tap water), affecting heating efficiency and even leading to overheating protection. After the power is turned off, the heating tube can be disassembled and soaked in white vinegar to remove scale.

Check if the wiring terminals of the heating tube are loose or oxidized, re tighten and apply conductive paste to ensure good contact.

If the problem is still not solved after the above investigation, it may be due to aging of the internal circuit or motherboard failure of the equipment. It is recommended to contact the maintenance personnel of Hubei Gaotian Test Equipment or the manufacturer's technical support to avoid secondary damage caused by self disassembly. In daily use, regularly cleaning the heating tube and checking the circuit connections can effectively reduce the occurrence of heating failures.