Home Automation

[AVpro]

Hi all. Please bear with me here as i have no idea really about air conditioning units but all you guys on these forums seem to know your stuff so hopefully you can help!

I work for a home automation installer. We have 7 Airwell units and 7 controlling keypads (1 for each unit). As far as we know these units and keypads seem to work on a RS485 bus. Using our equipment we wish to basically simulate one of the keypads so the units can be controlled by touch panel remote controls. We have connected our equipment to pins 1&2 on the fan coil so we are wired parrallel to the Airwell keypad. Looking at the manual for the keypads you can wire multiple keypads in this way. We are getting some strings back from the fan coil but nothing that makes any sense. We have integrated with many other systems in this way before but never a Airwell unit.

The strings that we are seeing come from the keypad are basically lots of 0's, so it looks like we have probably just got our RS485 port configured incorrectly. Does anyone out there happen to know what the baud rate etc. might be for these units? If anyone should have any information on this 485 bus and could shed any light on this it would be much apprieciated.

Thanks

[airefresco]

Have you tried contacting Airwell direct? If you don´t have it, there number is 0191 2221567. I would´ve thought that would be your best bet.

[Krondor]

Can you please provide the the exact type of the fan coils? What is the home automation equipment you are trying to connect to? As far as i know Airwell has a perfect solution that fits your needs.
Pm me and i'll give you a contact person from Airwell.

[Electrocoolman]

Surely the keypad will be the Master on the RS485 bus assuming RTU format. Is you controller also trying to be a Master too? or is it an analyser.
Alot of RS485 seems set for a default of 19,200 or 9600. Assume you've tried swapping D0 D1.

[electro]

It could well be because the devices use something like Manchester encoding, google that one, it's so that a clock signal can be sent over the wires along with the data.