The process of changing the protocol chip is described here.
Locate the temperature controller.
Easing the clips on the side, it is possible to pull out the controller.
After pulling the whole controller out, the empty slot looks like this.
This is the controller.
The order code that specifies the unit. The type of the communications protocol fitted is circulated.
List of wiring and (protocol)
- 2XX - No communications
- 2YM - 2-wire RS485 (Modbus)
- 2FM - 4-wire RS422 (Modbus)
- 2AM - RS232 (Modbus)
- 2YE - 2-wire RS485 (Ei-Bisynch)
- 2FE - 4-wire RS422 (Ei-Bisynch)
- 2AE - RS232 (Ei-Bisynch)
- 2DN - (Devicenet)
All of the above applies to the original setup, the protocol chip may have been replaced, so below is described how to see the same information from the actual protocol chip.
The communications module is the one in the middle covered partly with white plastic.
The module is attached to the main board with electric connector pins and a white plastic pin, visible on this picture. Squeezing the plastic pins top allows it to flow back through the hole, and carefully pulling the electrical pins out of their socket releases the module.
Removed communications module on the right. The wiring (422) and the protocol (Modbus) are printed on the plastic.
Bottom side of the module. Electrical pins top left, and the plastic pin on the middle.