Seeking help with Siemens ultrasonic level gauges
Thread Content
There are 2 Siemens ultrasonic level gauges; regardless of the output value, it shows full scale on the PLC. When checking the voltage, it’s 28V–30V. What’s going on? Is it necessary to add resistors? Thank you!
The voltage should be normal. It is recommended to first disconnect the on-site level gauge and directly apply a 4-20MA signal to the PLC channel; if the reading remains at full scale, then there is an issue with the setup, such as whether the unit of measurement is correct.
Issues with the PLC acquisition card or software configuration
Is there interference from high-voltage electricity? It’s probably interference voltage; check whether it’s direct current or alternating current