Determine the fault mode:
Yokogawa temperature transmitterIf the output signal is 4-20mA, then its fault phenomenon can be judged by its current output. For integrated temperature transmitters, external components should be the main focus during inspection. For example:

1. If there is no current output, the power supply should be checked for normal operation, and there should be no open circuit in the wiring. If everything is normal, the fault can be determined by replacing the transmitter

2. If there is a deviation in the output current, the measuring components such as thermocouples and thermistors should be checked for errors first. A standard meter should be used for measurement, inspection, and judgment. The connection terminals should also be checked for good contact and moisture. (In this case, it is recommended to replace it, as it is quite fast and cost-effective during our maintenance process.)

3. The fluctuation of output current is mostly due to poor contact and interference in the circuit, which can be determined by checking the contact condition of the circuit and measuring the interference voltage on the circuit to determine the cause of the fault (usually when we lay the instrument line, we separate it from the power line, and it is recommended not to have joints on this circuit. It is best to use soldering in areas with joints to reduce interference)