multiple M1XIN in single location


Senior Member
Ok guys, I spoke to Brad Weeks of ELK this afternoon. I asked him about connecting multiple M1XIN board to the M1DBH and that, there is only 1 CAT5 and it's already been used by the first M1XIN board.

What he told me is that, I should daisy chain all the M1XIN boards. The 12v+ from first XIN should be connected to the 12v+ on the second XIN, then another wire from the 12v+ of second XIN to the 12v+ on the third XIN, etc. Then the A & B terminals, same connection as the former.

I would like to know if the attached picture's wiring is correct.



EDIT: He also told me that I should terminate the last XIN board even if I had a terminator on the M1DBH already. Can anyone please confirm?


  • multiple_m1xin.jpg
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That all looks right but I would just want confirmation that you can put four devices in one "series" run. All the schematics in the manual show three and I couldn't find the maximum number spec when I scanned it quickly (and I mean quickly) :D
I will contact him again about the max number of M1XIN boards in series. Also, he mentioned that when testing, turn off system, use a meter to check the ohms. The reading should be between 60-70 ohms when meter is placed on each terminal on both end boards. If it goes beyond 70, or below 60, something is wrong.
Your what about this picture won't work as the buses need to be diasy chained. The M1DBH provides support for a star configuration.

But I'm confused why you are using the m1dbh in the first place, you can run two busses directly from the M1Gold panel. Why not just run the bus directly from the panel to your 4 XIN's that you diasy chain together. So it looks like your first picture, but connected to the M1 instead of the M1DBH.

And you need to terminate the last one on the bus regardless of how it's connected.
So is it ok to have M1DBH and the Daisy chained XIN connected to the M1 directly? RIght now, I only have 1 XIN card and it's connected to DBH. The reason I posted this is because, in my first floor can location, the CAT5 is already used. In the future, if I need to add more XIN, I will just daisy chain it like what is shown in the first drawing I have.

BTW, there's a post somewhere on here where spanky talks about using a multimeter to make sure your RS485 run is properly terminated.

EDIT: Here that's post. look at the 5/11, 7:16 post from spanky.

To make sure, turn the power off on the M1 and measure the resistance across the A and B terminals on the RS-485 data bus. A properly terminated data bus should read about 60 ohms +/- 10 ohms. 30 ohms means too many terminating resistor jumpers in place, 120 ohms means only one terminating resistor jumper in place.