Elk and Aprilaire, 483 vs 232

[asteinmetz]

I was under the impression that since there is an RS 485 data bus on the Elk M1G and the Aprilaire stats use the 485 protocol, I would not need the Aprilaire protocol adapter that converts 485 to 232. Now that I have the Elk M1XSP interface I see I may be wrong.

Indeed, the instructions that come with the Elk M1XSP call for putting the RCS thermostats on directly on the 485 bus but the instructions for the Aprilaire that Elk provides call for the Aprilaire 8811 adapter to plug into the RS-232 jack on the M1XSP.

Can't I hook the Aprilaire 8818 distribution panel directly to the 485 terminals on the Elk M1XSP and avoid the extra hardware layer? Thanks.

 

[Spanky]

You will need the M1XSP Serial Port expander which will talk to the Aprilaire RS485 module which talks to the Aprilaire thermostat. Aprilaire has one of the more complex interfaces.

The M1 RS485 data bus is NOT protocol compatible with the Aprilaire directly.