RS485 Modem with AC Current Monitor

Hi everyone, I’m working with the following structure:

  • One AC current monitor PR52-7 (Type 00D0).
  • A RS-485 Modem PR55-17C (Modbus RTU).
  • A RS-485 to Ethernet gateway, just to read information over ethernet.
  • As another option to communicate with the modem: USB to RS-485 converter.

Communication between sensor and modem was pretty easy to implement, even with the gateway or USB converter, everything works Ok.

When I tried to connect this with Alpha Station to set some parameters, I couldn’t communicate with the sensor. I tried to enter configuration mode, but at this moment, it has been impossible, even though I tried in different ways:

  • Press R and C button at the same time, release R and let pressed C for 6 seconds.
  • Press R and then press C for 6 seconds.
  • Press R and then press C for 2 seconds.
  • Turn OFF and Turn On the sensor, and then press C for 2 seconds.

I my case, PAN ID never changed from 7FFF.

How can I solve this according with the structure that I have?

Thanks everyone!