Hard wired sensor state input

[AutomatedOutlet]

Thanks Digger. I knew someone on this board would know the exact specs!

 

[Digger]

I have one of those monster motorcycle-battery sized Elk batteries for my 2ndary panel that has most of my sensors, the regular one running just the mainboard and a few sensors.

I haven't timed it, but the #s insinuate well over 24 hours.

If you go to Costco they have an 85 aH deep discharge battery for under $90 if I remember correctly. One of these days I am going to pick up a few for my system. I would like to get to 48 hrs of battery backup. The problem would be that the ELK would not be able to recharge them once they are discharged (the ELK should maintain one of them on a trickle charge).

I have a bunch of 1 A and 2 A automotive battery chargers I can use and a larger one for a deep discharged battery.

 

[IVB]

85 amp-hour? Jesus; my huge one is the Elk 26aH.

How much stuff do you have that 85aH only gets you 48 hours? And you want a few of them?

 

[Digger]

85 amp-hour? Jesus; my huge one is the Elk 26aH.

How much stuff do you have that 85aH only gets you 48 hours? And you want a few of them?

About 3 amp load all together. It adds up fast.

1 control unit approx. 150 ma
4 keypads approx 800 ma
3 zone expanders approx 200 ma
2 relay boards approx 150 ma
2 serial expanders approx 150 ma
1 ethernet adaptor approx 300 ma
1 rf receiver approx 100 ma
5 motions approx 200 ma
7 smokes approx 150 ma (with 7 EOLR)
5 CO Detectors approx 120 ma (with 5 EOLR)

and some misc things such as the ABN, router etc needed for communication to the CS

So about 75 ah a day would need 2 batteries for 48 hours.

 

[IVB]

crap. I better go recount all my stuff. The sensor list has been growing lately. I thought I had plenty of headroom, but I may have eaten into that...

 

[Photon]

I've used an Accumate battery charger/maintainer on my Miata AGM battery all winter when it stays in the garage. It's in its 8th year, and still cranks like a champ. Battery Tender is a more popular microprocessor-controlled charger/maintainer. If I eventually need a huge battery for my Elk system's accessory boards and sensors, I'll probably get an AGM Deep-Cycle battery and another one of these computer-controlled charger/maintainers for it.

 

[Digger]

crap. I better go recount all my stuff. The sensor list has been growing lately. I thought I had plenty of headroom, but I may have eaten into that...

24 hours is typical standby. 48 is not necessary unless you feel you are in an area where a prolonged outage is a real possiblity.

I figure that within 2 days of a power outage I could fire up the generator long enough to recharge the batteries enough to get through another day etc.

BTW I have a few wireless smokes that act as standalone units if the panel is down. That is also a redundant feature of the system. I put one on every level of the house.

 

[IVB]

Well, it was a good reminder anyhow. I put a 3rd expander, 3rd keypad, wireless receiver, and output relay on the bus after I had done my backup calculations.

I realized that at this point i've got 7 hours of backup on the mainboard (8aH battery), but 65 on the 2ndary panel(26aH) as I just remembered I wired the M1DBR to power off the mainboard. Given that it's easy to add a 3rd battery, your post made me decide to run the M1DBHR and all bus devices off a 3rd power supply/battery. I only have .7A on the bus, so I could shuffle things around to get at least 24 hours everywhere.

Thanks again for the prod.

 

[Digger]

Well, it was a good reminder anyhow. I put a 3rd expander, 3rd keypad, wireless receiver, and output relay on the bus after I had done my backup calculations.

I realized that at this point i've got 7 hours of backup on the mainboard (8aH battery), but 65 on the 2ndary panel(26aH) as I just remembered I wired the M1DBR to power off the mainboard. Given that it's easy to add a 3rd battery, your post made me decide to run the M1DBHR and all bus devices off a 3rd power supply/battery. I only have .7A on the bus, so I could shuffle things around to get at least 24 hours everywhere.

Thanks again for the prod.

I am sure you would have realized it once the power went out

Trust me I dont have enough battery backup at the moment myself. Thats why I want to get the large batteries. Much more economical.