Trane Chiller UC800 Controller Inerface

Just seeing if anyone out there has successfully interfaced a trace chiller UC800 controller to Opto via either Modbus or BACNET??

Currently having a few issues with both. Modbus im using a mgate modbus gateway to convert the Modbus RTU to Modbus TCP/IP. Im using modbus poll to check the data coming out and all that it keeps coming back with illegal packet length.

Bacnet I can see the UC800 and can read the object names but cant read any of the actual values. I can see both object names and values when using the test program ‘bacnet discovery tool’.



I’ve got to start with a background question: Mgate serial port settings match UC800? I have used the Moxa Mgate for a number of applications and had success with all. Haven’t interfaced with the Trane Chiller though. Some manufacturers limit what modbus code you can use to access registers, though I didn’t see that limitation via a cursory review of the Trane manual.

Thanks for the reply.

Yes, ive set the mgate serial settings with the same settings as the trane chiller. Even changed the baud rate and others but no good.

I’ve used these mgate’s on other devices and have had success, but can’t get it going on the trane chiller. Thought Id see if anyone else had issues before I contacted trane, but I think i have to get onto trane and find out a bit more.

Had bad luck with BACNET. We had to give our customer a free controller just to run the BACNET charts as intended (because of controller resource issues). At the time the website information led us to believe that we could just run a BACNET chart and all would be good. It turned out that in our case the BACNET load (charts) were too high for what had seemed like a simple interface. We have had better luck with Modbus, it seems much lighter than BACNET. I think they re-wrote the BACNET integration kit, but we wound up loosing the customer over it.

I have established communication to a Trane Chiller with a UC800 before. To do this the Trane technician needed to set the UC800 for Modbus communications and then I believe we set the address using the turn knobs. I wrote a custom subroutine but you should be able to use the Opto Modbus drivers. I did not use any 3rd party converters just RS485 to the UC800 and make sure it is setup by Trane for Modbus.