I'm not sure I'm following DEL's comments... What you're trying to do with the aux. power supplies is exactly what they're intended for to solve the problem you're looking at - power draw on the overall bus (and/or powering accessories).
If you look at the installation guide for the P212S, there are specific installation notes for using the P212S to boost the databus.
Here is an excerpt:
Since you can't access that portion of the site (only available to dealers or owners) I'll PM a copy to you.
Based on that, your downline expanders will be pulling off the auxiliary supply, not the Elk's main supply. You can continue to add more of these power supplies to handle anything you attach to the M1. Of course you want to make sure no single power branch exceeds what its's rated for.
I was referring to the power supply does nothing to extend or boost the 485 bus, which is DATA A and DATA B, which is limited to the 4000'. It only provides additional aux power output to connected loads so they can be shed off the panel, and the supply itself supervised by the panel for trouble conditions via the 485 bus. The power connection is different than the 485 connection, since the 212 only uses 3 wires to connect to the panel, and other boards downstream do the same,
with the exception that their power is drawn off the supply's output on the bottom of the 212.
Wuench- The M1's bus really doesn't provide that much power when you factor in any expansion boards and their draw, so power supplies are quite common and necessary when integrating a decent sized M1 that has expansion boards installed or even a moderate alarm panel by any other manufacturer. The methods he's considering, or at least I'm envisioning using the XOVR and M1RB is no different than what I believe you're proposing using other hardware.It would not be prudent to design the system without considering the current draw of all the peripherals in a full/max draw state, otherwise that is engineering in a failure out of the gate. 30 relays or outputs really isn't unheard of or excessive, depending on what the M1 is being used to control or integrate with.
Here's the facts as I know them:
The LV lights are driven off a few 120V transformers, which he wants to break up into zones/areas and control individually. Switching the 120V here would only do a generic on/off per transformer and not control the loads connected to the transformer, which does not match the "zone/area" that the OP would like to control.
There are sprinkler valves/irrigation controls being desired, which requires a relay per valve/zone
Any other need that may arise to use a relay, such as OHD opener, alarm power reset, LED for arm status, what have you.