M1XSP and zone epander

[tunafishhkg]

Does anyone have the diagram on how to wire the M1xsp and a 16 zone expander to the M1 with one home run? I
All three moduals are showing they are enrolled but the serial to my omnistat2 will not work after adding the zone expander but was working before that.
Thank you

 

[Steve]

We may need a little more info on what you have and how its wired, but in general, both ENDS of the RS485 bus need to be terminated, If you have 1 xsp hooked to the M1 then both the panel and the XSP need a terminator. If you have 2 devices (like XSP and expander) homerun to the M1 then each device needs a terminator and no terminator on the panel (each device on the end of 2 homeruns would be considered the ends of the bus with controller in the middle). More than 2 homerun bus connections and you should use a hub. If you had just 1 xsp connected to the panel and it worked then both the panel and xsp are probably terminated. So, if you added a second line (expander) to the controller (2 wires now in RS485 connection)you probably need to add terminator to expander if not there and remove terminator from the panel. Make sense? The other option would be to wire the new expander to the xsp and xsp to panel (existing line). In that case you would terminate the expander and the panel (panel is one end and the furthest device is the second end - no terminator on middle devices). If you are handy and have a multimeter, you can measure resistance between Data A and B on the panels RS485 connector with the power off. It should be around 67 ohms +- 10 or so.

 

[jaysonc]

I think you are looking for this:

Elk Panel <---Terminate the RS485 Bus Here. (JP3 should have a jumper on it)
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M1XSP <--- This component should NOT termination the RS485 Bus (JP1 should NOT have a jumper)
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Zone Expander <--- This component should terminate the RS485 bus (JP1 should have a jumper over pins 2 & 3.)


In general, no matter how many devices you have on your bus only the two devices at the ends of the cable should be terminated.

Two things of note:

1. If your bus continues past your Elk to other components (keypads, etc.) then your Elk would no longer be at the end of the cable, and should not be terminated.

2. If you are using either of the Elk RS485 bus products (M1DBH or M1DBHR), the above diagram is too simplified to be useful. You need to look at the diagrams Elk provides in the M1DBHx instruction manual.

--
Jayson

 

[tmbrown97]

are you using a DBH but only have 1 cat5 back to the panel, and want to connect both to that single home-run cable?

Just an assumption - but if that's the case, it's pretty simple. Wire the Cat5 end as normal, and on the other end - use little jumpers or something so you can wire the two units exactly the same into the one length of cat5 - it should work just fine. Just don't screw with any termination jumpers - let the DBH do that.

 

[tunafishhkg]

Thanks for the replies. I called elk (very helpful) and Brad said I had it wired OK, (only need jumper on jp-1 yes) as it was. The keypad is wired to M1 data along with the xsp. The zone expander is wired into XSP, I believe a parallel connection. Keypad shows modules and I Tried to cycle fan and also reboot but still showing thermostat temp not enabled and I have no control. Since it did work before I added the zone expander, He said to download new firmware for the Omnistat2 and is e-mailing the latest installation diagrams just incase. Lets see after firmware update. Thnks again!

 

[Spanky]

Adding the zone expander should not affect the M1XSP. Just for test, try disconnecting the zone expander and see if the thermostat starts working.

 

[tunafishhkg]

Hi, got the Omnistat2 to work after firmware update but still can not read omnistat2 temp? Keypad says not enabled but at least, I can now set rules and tasks on the M1. I just can not remotely, or from keypad, get the single Omnistat2 to output temp.
Thanks