1. Warm up for a while and the temperature does not change. Always show the ambient temperature (eg room temperature 25 ° C)

First of all, we must first check whether the SV value setting value is set, the meter OUT indicator is lit, and use the "multimeter" to measure whether the meter's terminals 3 and 4 have 12VDC output. If the light is on, the 3 and 4 terminals also have a 12 VDC output, indicating that the problem is with the control device of the heating element (eg, AC contactor, solid state relay, relay, etc.). Check whether the control device has an open circuit, whether the device specifications are incorrect (such as the 380V device in the circuit of 220), and whether the line is connected incorrectly.

2, heating for a period of time, the temperature display is getting lower and lower

In the case of such a fault, the positive and negative polarity of the sensor is generally reversed. At this time, the meter sensor input terminal wiring should be checked.

3. When heating for a period of time, the temperature value (PV value) displayed by the meter is very different from the actual temperature of the heating element (for example, the actual temperature of the heating element is 200 ° C, and the meter shows 230 ° C or 180 ° C)

In case of such a fault, first check whether the contact point between the temperature probe and the heating element is loose or not, whether the temperature point selection is correct, and whether the temperature sensor specification is consistent with the temperature controller input specification.

4. The meter PV window displays HHH or LLL characters.

In the case of such a fault, it indicates that the signal measured by the meter is abnormal (the LLL is displayed when the meter is measured below -19 °C, and the HHH is displayed when it is above 849 °C).

5. The control is out of control, the temperature exceeds the set value, and the temperature is always rising.

In case of such a fault, first check whether the meter OUT indicator at this time is lit, and use the DC voltage of the "multimeter" to measure whether the 3 and 4 terminals of the meter have 12VDC output. If the light is off, there is no 12VDC output for terminals 3 and 4. It indicates that the problem lies in the control device of the heating element (such as; AC contactor, solid state relay, relay, etc.).