Mahmood sends his apologies, but he couldn't post at the weekend, and he has three days in the UK this week.

Anyway, I like the uLAN idea for say, a REAL 3000 room building or whatever, but surely where it IS practical to run 6000 wires, the LAN is going to be truly over the top , especially since the customer appears to be penny pinching ?

It would be a very poor engineer who attempts to shoehorn his favourite solution onto a problem rather than the best solution !

Solutions involving CAN buses, multiple processors, redundant comms protocols etc. seem to me to ignore the fact this is a MODEL of a building, basically to look pretty, not a prototype for some kind of HVAC system.

Steve