Connecting a Caddx Solution 2000 to an ELK M1 Gold


Active Member
Greetings from Colombia

I had Homecontrols design my alarm system and bought all the devices from them.

They spec'ed a 4-wire connection to the glass break sensor, which we duly installed.

Come to find out, the sensor has a pwr/gnd, N-NC, Tamper and Reset pairs. Obviously this should have been wired with more than 4 wires...

Now, I'm looking for a way around this:

One pair goes to pwr/gnd

The tamper contacts lead to a micro-switch (NC, when cover installed). I was thinking of connecting one contact to GND and pulling the other to PWR with a resistor and using one of the remaining wires to connect to an ELK input. If it gets tampered with, and the contact opens, the ELK senses the input going up to PWR.

Will this work?

Likewise, on the actual glass break sensor, I would connect C to GND. As before, NC gets pulled to PWR. When triggered, NC pulls high and the remaining wires triggers the ELK...

Will this work?

Any additional hints (how to program the ELK input, what resistor to use, use SAUX to reset? etc) are, as always, highly appreciated!



Senior Member
Normally, you would wire the tamper switch is series with the sensor contact.  If either one becomes open, it will trigger an alarm. If it was a sensor trip, the alarm LED will be latched on.  If it was the tamper switch, the LED won't be lit.
The M1 puts out a voltage on the zone loop.  You don't want to connect it to +12V through a pullup resistor. 
If you want the tamper contact on it's own zone, you could do the following:
M1 +VAUX to sensor PWR
M1 NEG to sensor contact  COM terminal, and to tamper COM, and to sensor GND.
M1 zone A input to sensor NC
M1 zone B input to tamper NC
The above assumes you have no EOL resistors.  If you do have EOL resistors, place them on the sensor contact wire that goes to the zone input.  Best practices says the EOLs should be on the NEG side of the contact, but since you are sharing that one wire for power and two zones, you can't place it there.
If you want to use the reset function, you'll need another wire, or will have to combine the tamper and sensor contact into a single zone.  SAUX would not be the right place to connect the reset to - it's meant for smoke detectors and would only reset when you issue a Smoke Reset via the keypad.   A better choice would be to use a M1 voltage output, and write a rule to turn the output on when the alarm system arms.


Active Member
Thank you yet again RAL!

I'll use your suggested standard configuration with Tamper and sensor in series along with the EOL. And use an M1 Output to drive the resets.



Active Member
Hello RAL.

I ended up with your suggestion:

1- common ground, tamper and sensor in series, with EOL on one of the remaining leads and

2- using an output to pull the reset negative with a rule.

Works like a charm!