Which Elk battery and how long should it last?

[johnnynine]

I currently have an ELK-1208J2 12V-0.8Ah(?) elk 8Ah battery powering an Elk M1 system with 40 zones, 2 input cards, the ethernet module, serial hub card, and a relay card.

The battery has lasted about 3 years and I am now getting a Low Battery message on my keypads, is this a normal lifespan?

I see Elk has several other batteries, am I using the appropriate battery?

Thanks,
Johnny

 

[Digger]

There is a menu item that allows you to measure your standby current on the keypad. See what that is and multiply that by 24 if you have any fire devices (you can go less if you want but that is what the NFPA specifies). That will tell you how many amp/hours you need and round up to the next size battery. The M1 can charge up to 18 aH of battery although I have a 26 aH on mine with no problems (might take a little longer than it should to recharge).

 

[Sandpiper]

I currently have an ELK-1208J2 12V-0.8Ah battery powering an Elk M1 system with 40 zones, 2 input cards, the ethernet module, serial hub card, and a relay card.

The battery has lasted about 3 years and I am now getting a Low Battery message on my keypads, is this a normal lifespan?

I see Elk has several other batteries, am I using the appropriate battery?

Thanks,
Johnny

At first I thought the 0.8 was a typo, and that you meant an 8.0 AH battery. But I looked up the battery model and indeed you have a 0.8 AH battery. The "standard" battery size for a vanilla alarm system is 4.0 AH, and the standard for an M1 is an 8 AH. I think you should upgrade to at least an 8 AH. I have two 8 AH in parallel, but as Digger pointed out, if you have smokes, you should 24 hours of standby time. The NBFAA recommends a minimum of 4 hours of standby time for a burglar alarm system.

Digger, thanks for pointing out the current measurement on the ELK keypad (menu item 8-6-2). That is pretty handy.

As for battery life: a well maintained sealed lead-acid battery should last anywhere from 3 to 5 years. But an undersized battery will probably end up on the short end of this- namely about 3 years.

 

[johnnynine]

You are right, it is a 8Ah battery... The only battery I saw on AO with an "8" in it was the 0.8 amp so I assumed that was it... since I can't find a model number on my battery.

Sorry for the typo.

The elk reads 13.8v, .065ma. .065 * 24 = 15.6, but I don't have any fire devices on the system.

Johnny

 

[Digger]

You are right, it is a 8Ah battery... The only battery I saw on AO with an "8" in it was the 0.8 amp so I assumed that was it... since I can't find a model number on my battery.

Sorry for the typo.

The elk reads 13.8v, .065ma. .065 * 24 = 15.6, but I don't have any fire devices on the system.

Johnny

I think it may read 0.65A

Personally I would go with two 8 aH batteries (in parallel) which will give you the 24 hours of battery backup up (it will go down in a few years) even if you dont have any fire devices. Just now the storm is knocking out power here on Long Island. My sister in law lost power a little while ago and the power company estimates maybe another 5 hours before it is back on.

 

[Sandpiper]

You are right, it is a 8Ah battery... The only battery I saw on AO with an "8" in it was the 0.8 amp so I assumed that was it... since I can't find a model number on my battery.

Sorry for the typo.

The elk reads 13.8v, .065ma. .065 * 24 = 15.6, but I don't have any fire devices on the system.

Johnny

Not another typo??? It has got to be 0.65 A. (With a similar system, my system draws about 0.55 A) Assuming this is the case, an 8AH battery will give you approximately 12 hours of standby time. (8 AmpHours / 0.65 Amp = 12.3 Hours)

Putting a second battery in parallel adds an additional complexity which may not be worth it in your case. (Some wire splicing, fusing concerns, etc). One 8AH battery fits nicely in the M1 cabinet, where two require additional complexity.

 

[Digger]

You are right, it is a 8Ah battery... The only battery I saw on AO with an "8" in it was the 0.8 amp so I assumed that was it... since I can't find a model number on my battery.

Sorry for the typo.

The elk reads 13.8v, .065ma. .065 * 24 = 15.6, but I don't have any fire devices on the system.

Johnny

Not another typo??? It has got to be 0.65 A. (With a similar system, my system draws about 0.55 A) Assuming this is the case, an 8AH battery will give you approximately 12 hours of standby time. (8 AmpHours / 0.65 Amp = 12.3 Hours)

Putting a second battery in parallel adds an additional complexity which may not be worth it in your case. (Some wire splicing, fusing concerns, etc). One 8AH battery fits nicely in the M1 cabinet, where two require additional complexity.

Two batteries fit side by side in the 14" enclosures of the M1. Fusing is not required if in the same cabinet etc (but someone can if they want).

Adding a second battery for 24 hours of battery backup has its advantages. It will be that much longer before a low battery occurs, it will keep the system running longer, and allow for future expansion.

Its a personal choice when there are no fire devices on the system.