Basic electrical and alarm panels 101:
The panels connected the Telgard are irrelevant, any panel that supports CID, O/C reports, keyswitch arming and has an output or outputs that change based on arm status would be compatible. Anything can be modified for voltage polarity, etc. via a relay.
The Elk's triggers on out 7-16 are a positive trip. You could, if absolutely necessary, use Out 3, but that is honestly easier to leave for another purpose and switch a higher load. The M1 and EZ8's trigger outputs are +12V, not an open collector, with limited current. You could use a 912, but it'll draw more current. I prefer to leave OUT 3 for other purposes due to the nature of the equipment we install and installation methods, which are a whole different discussion.
Take a look at the diagram you posted and think of it differently and look at it clearly. The TG and the trip is just like a zone on any other panel with the TG as the alarm panel. When closed to COM on the panel, the TG sees a 2.2K EOLR (internal) so it knows the alarm panel is armed and connected. If it sees nothing, then it's viewed as disarmed. The host alarm panel is switching the COM leg of the "zone" in this case. You can't provide a +voltage to the trip and expect it to work without letting the magic smoke out, it's direct short from the panel's aux power to COM. The open and close reports are also what are captured by the unit and used as a second form of verification for the app. With some exceptions, all panels sold in NA have the aux power COM and ZCOM common to each other, and any additional power supplies are always wired with them being common to the panel's negative COM as well, nature of the beast.
The 924 is constantly powered, per se, with the T+ from any OUT 7-16, which causes the coil to fire in the case of the M1. That provides a dry contact on the other side of the relay. You're going to end up feeding the COM through the dry contact of the relay. The rule itself vs. the triggers having power would determine which terminals (NC/NO) you connect to the TG, with COM being connected to panel COM. No voltage, just switching the COM of the panel via a positive trigger in the case of the M1.
The benefit of using a 924 in this case with the DPDT relay is the benefit of a second isolated relay that would allow you to install a LED for armed status, which we commonly do for keyfob arm verification, very easily with no additional programming and minimal wiring.
If you wanted to add the expense or already had one installed, you could use an output expander on the M1 panels to do the same, but the difference in many of our cases is adding a single $5 relay vs the cost of an XOVR or M1RB and not using them to their full ability.
The panels connected the Telgard are irrelevant, any panel that supports CID, O/C reports, keyswitch arming and has an output or outputs that change based on arm status would be compatible. Anything can be modified for voltage polarity, etc. via a relay.
The Elk's triggers on out 7-16 are a positive trip. You could, if absolutely necessary, use Out 3, but that is honestly easier to leave for another purpose and switch a higher load. The M1 and EZ8's trigger outputs are +12V, not an open collector, with limited current. You could use a 912, but it'll draw more current. I prefer to leave OUT 3 for other purposes due to the nature of the equipment we install and installation methods, which are a whole different discussion.
Take a look at the diagram you posted and think of it differently and look at it clearly. The TG and the trip is just like a zone on any other panel with the TG as the alarm panel. When closed to COM on the panel, the TG sees a 2.2K EOLR (internal) so it knows the alarm panel is armed and connected. If it sees nothing, then it's viewed as disarmed. The host alarm panel is switching the COM leg of the "zone" in this case. You can't provide a +voltage to the trip and expect it to work without letting the magic smoke out, it's direct short from the panel's aux power to COM. The open and close reports are also what are captured by the unit and used as a second form of verification for the app. With some exceptions, all panels sold in NA have the aux power COM and ZCOM common to each other, and any additional power supplies are always wired with them being common to the panel's negative COM as well, nature of the beast.
The 924 is constantly powered, per se, with the T+ from any OUT 7-16, which causes the coil to fire in the case of the M1. That provides a dry contact on the other side of the relay. You're going to end up feeding the COM through the dry contact of the relay. The rule itself vs. the triggers having power would determine which terminals (NC/NO) you connect to the TG, with COM being connected to panel COM. No voltage, just switching the COM of the panel via a positive trigger in the case of the M1.
The benefit of using a 924 in this case with the DPDT relay is the benefit of a second isolated relay that would allow you to install a LED for armed status, which we commonly do for keyfob arm verification, very easily with no additional programming and minimal wiring.
If you wanted to add the expense or already had one installed, you could use an output expander on the M1 panels to do the same, but the difference in many of our cases is adding a single $5 relay vs the cost of an XOVR or M1RB and not using them to their full ability.
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