Elk M1 setup, power question

[chrisexv6]

I have my M1 setup almost ready go to. Quick summary: Uplink 2500, M1G, 4 motions, 4 glassbreaks, internet module, zone expander, DBH and a fire system (6 2WTA-B alarms, RRSMOD and 2W-MOD2)

Obviously this setup calls for more power, the Uplink 2500 needs its own supply basically (since they say to make sure you can feed it 2.5A)

Since everything except the M1 itself can run on 12V, I was thinking about picking up a 12V power supply capable of 13A (Cosel....good stuff!) BUT the only wrinkle I see is that all of the boards that Elk sells with the master power cutoff switch/low battery disconnect/battery charger built in only take 16.5V in (check the board in their P412 power supply)

Is the power supply in the P412 can actually 16.5V? That one is only 4A and if I wanted to use it to power all of the accessories (internet module, fire system and Uplink) it barely clears the max amount of all of those items. Obviously 13A would be overkill, but at least I could have one central supply for everything minus the M1.

Has anyone done anything like this before?

 

[Linwood]

The M1G can be driven entirely on 12V, there is a jumper you set to allow it to start without AC. Of course you need to worry whether the (only) 12V supply then is supervised properly since if it quits you get nothing.

 

[chrisexv6]

Thanks, didnt know that....my bigger question still remains though, how do you take a 12V power supply (ive seen a bunch of recommendations for an Altronix unit that is 12V) and have it charge a battery while providing power to the Elk/accessories?

 

[apostolakisl]

A UPS powering your 12v supply would be necessary. However, Elk will not be able to test the UPS as it does its own battery. So you would need a UPS that self tests and has a relay or something to report to the Elk that it is failing.

But, I would highly recommend you use the standard power supply/backup battery for the Elk main board, smokes, and the zone expanders. You can use your aux 12 source to power everything else. If the aux power supply dies the system will still function, at least from the standpoint of a local alarm.

 

[chrisexv6]

A UPS powering your 12v supply would be necessary. However, Elk will not be able to test the UPS as it does its own battery. So you would need a UPS that self tests and has a relay or something to report to the Elk that it is failing.

But, I would highly recommend you use the standard power supply/backup battery for the Elk main board, smokes, and the zone expanders. You can use your aux 12 source to power everything else. If the aux power supply dies the system will still function, at least from the standpoint of a local alarm.

This is true, I was thinking I will move the 12V to things like the glassbreaks and motions. BUT it doesnt really save me much. With the fire setup needing about 1A, the Uplink needing about 2.5A.....I obviously cant connect all of that to the Elk.

What would be your suggestion to keep the bare minimum running *and supervised*?

 

[apostolakisl]

Personally, I use an aux power supply with a 12 and 5v output on it. It powers everything that is 12 or 5v except for the main board, zones, and smokes. I have a hai c3 unit for my cellular connection, it is also on the aux supply but it has a built in battery backup. Things like glass breaks and motions use so little power that I would not bother, plus they are part of the true security system. I have no glass breaks but motions are still on the Elk's power.

Things like relay boards can be taken off of Elk's main power since you are probably not useing them for any security purpose. Relays can eat a significant amount of juice if you start turning a bunch of them on at once.

My xep, relays, RF transmitters, modem, router, switches, cameras, rf receivers (keyfob) are all on the aux power (and probably more stuff that I just am not thinking of right now). I was able to elliminate about 15 wall warts. Side bonus, the aux power supply makes much cleaner power (meaning my router doesn't need reboots anymore).

 

[chrisexv6]

How much draw do your smokes take when on alarm? Since Im looking at smokes with sounders built in, its adding up to about 920mA in full alarm.

Thats too much to come off the main board of the Elk as it is.....are your smokes taking much less current than that?

 

[Del91574]

You can, although I wouldn't recommend it, use a secondary power supply to run the M1 itself and fake out the charging circuit of the M1, but that would negate a lot of what the M1 has going for it.

I would install a second supply (larger) and loadshed all but what is essential on the M1 to it and size a battery appropriately. The one item you need to watch with an M1 and an aux supply is any bus devices powered off the supply need to have 12V as a minimum otherwise bad things happen. Many separate power supplies (some Altronix included) lose a volt in transition when their AC is removed and running on battery only, so a normal 13V battery float current is already at the threshold.

I'd recommend staying away from a secondary UPS based setup and get an appropriate supply and then worry about the LB cutoff aspect of the supply.

Once you get into the larger supplies, you're looking at either installing a plug in whip or hardwiring to a branch circuit.

I'd recommend something like a SMP10PMC12X or an SMP7PMC12X and LBD for what you're looking at, from Altronix, and then install appropriately sized batteries. If you shed all but the basic loads from the M1, your backup size there is less. Supervision would be done via a zone on the M1 (power supervision ZT) and AC can be supervised if truly desired, however I wouldn't worry about it.

 

[apostolakisl]

How much draw do your smokes take when on alarm? Since Im looking at smokes with sounders built in, its adding up to about 920mA in full alarm.

Thats too much to come off the main board of the Elk as it is.....are your smokes taking much less current than that?

I'm using 4 wire smokes (GE 449 cst plus one 449 cste). They consume 10ma (33ma for the cste) in reverse polarity mode and practically nothing in standby (70 micro amps and 33ma respectively). I have 10 of them so 123ma total in alarm and 82ma in standby.

 

[Linwood]

I suspect if you want extra power you would find the P212S a much more integrated solution. Full supervision, automatic battery tests, etc. I just added one to mine, and it was a bit pricy but it all works and plays very nicely together.

 

[chrisexv6]

Thanks everyone.

I went with the SMP7PMC12X (12V, 6A supervised)

I know the P212S is a more integrated solution, I just didnt like the fact that Id need to buy at least 2 of them for it to complete the system.

6A is plenty for the Uplink, smokes and ethernet module. I have at least one zone expander so I can afford the zone to supervise the power supply.

EDIT: my bad, I didnt realize there is much less power draw with the alarms in reverse polarity mode. Looks like I can power all of the alarms off the mainboard. Would still need some other supervised power supply. The 212 might have been a valid solution after all if I dropped the requirement to supervise power to the Uplink as well.

 

[Del91574]

Since the power calc was wrong, what you can do is loadshed the entire system, per se, to the supply and increase the standby time of the panel itself, provided a valid calc is done for the items moving from the panel to the supply.