Analysis of Common Problems of Temperature Controller

1. No display after power-on.

Answer: Check if AC 220V voltage is available. There are fuses on some temperature control instruments, and you need to check whether the fuse is normal.

2. PV temperature display column on the temperature control instrument displays the maximum value of the temperature control range or HHHH?

Answer: After this happens, it can basically be determined that the thermocouple is disconnected.

3. PV temperature display column of temperature controller display a negative number.

Answer: There are two possibilities. One is that the positive and negative poles of the thermocouple are reversed, and another may relate to refrigeration, which is a normal phenomenon.

4. PV value of temperature control instrument deviate from the actual temperature.

Answer: It can be corrected by the temperature correction function in the temperature control instrument.

5. The temperature control instrument is not accurate since the temperature becomes higher.

Answer: Generally, it can be adjusted through the self-tuning function, and also through PID. At the same time, we can also adjust the maximum output percentage of the temperature controller.

6. The resistance value of heating tube and the PV value of temperature controller is normal, indicative of slow temperature rise when being heated.

Answer: Check temperature controller for the setting of maximum output percentage.

7. The alarm output of temperature controller is abnormal.

Answer: Check the customized alarm output terminal of temperature controller and whether the alarm settings are correct.

8. When the temperature controller reaches the SV value, the heating does not stop.

Answer: Check the control components, contactors, SCR, etc., and whether the temperature control instrument is controlled automatically or manually.