Connecting GE PQM's


Thread Starter


I need info on connecting 4 GE PQM for monitoring using a PC. If I need to monitor it using wonderware, what PC Card do I need? How are these PQM's configured? Do I need another software? Feedbacks most welcome.

Steve Bailey

The information I have on hand is a couple of years old, but according to it, the PQM uses Modbus RTU protocol. You configure it using a software package called PQMPC, which is supposed to be free. I suggest contacting your nearest GE sales office.
GE has a Power Management software package called GE PMCS - included is a modbus server called GE32modb. The PQM mnemonics and register mapping is already done for you. GE32modb can collect your metering, event, waveform, and setpoint data and serve it up via DDE (OPC will be supported in a future version, but dont hold your breath). Included in the software package is an Event / Alarm viewer program and waveform viewer.

Wonderware can act as your DDE client gathering data from your GE server.

What PC card do you need? To talk modbus you will need a RS485 connection. If you have only 4 PQMs and they will be daisy chained together, you can use your existing PC com port and buy an external RS232 - RS485 converter. If you need
multiple rs485 ports, use an external port device such as a systech gateway or digiboard.

Email me if you need more assistance; I have configured and installed a lot of projects with PQMs.


[email protected]
All the information you need can be obtained from the GE website at:

The PQM is equipped with three serial ports, two RS-485 2-wire and one RS-232 and it communicates using Modbus RTU at up to 19.2k baud. The RS-232 port which is on the front of the unit should be used for configuration purposes. You can multidrop the RS-485 provided you give each unit a unique address. If you need an RS-232/RS-485 converter to link in your PC there are a number of good sources including GE Multilin and
B&B Electronics.

Word of warning, data in the PQM is scattered over a vast number of registers, to minimize data read requirements you can configure the unit to move selected registers into a contiguous data area.

Your Wonderware package will require the Modbus driver in order to communicate.


Ian Milne
Upside Engineering Ltd.
Calgary, Canada

Eduardo Pelegrin

I have done this connection, but using Citect. The connection is done through the PC Com Port and using an RS 232/RS 485 adapter. The Citect and PQMs are linked together via Modbus binary protocol.