http://www.atbatt.com/home-alarm-battery.asp
The best ways to replace home alarm battery.

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Oursaibabasays

I have changed my alarm battery, but the problem still persist, triggering the alarm once a while in couple of days, until I just press any random button.. Please help.

Ah = amp-hours, not amps. Short out a 7Ah battery and you’ll get a damned sight more than 7 amps!

Ignoring Peukert’s law for a moment, a 7 Ah battery will put out 7 amps for 1 hour, 1 amp for 7 hours, half an amp for 14 hours, and so on.

When you brink Peukert’s law into play you find the Ah rating is typically based on 20 hours, so it’ll put out about 300mA for 20 hours. The higher the current draw, the lower the capacity (so you’ll get more than 7Ah if you draw less than 300mA, less than 7Ah if you draw more than 300mA).

Also, as zx3zx4 pointed out, the formula is wrong. Using your formula (1.39Ah per hour) results in 1.39×24 = 33.36Ah for 24 hours’ runtime, even though the panel states 17.2Ah will do. The correct multiplier to use in the formula would be 0.717Ah per hour.

Good info to know if (like me) you inherited one of these systems when you bought the house and were not involved in the original purchase or installation. Sure, replacing a battery is not difficult, but it is nice to have the basic info about what to look for easily available.

This is one of the few videos that explains the need to pay attention to the F1 or F2 size clip. Thanks for pointing that out, so I could order the correct replacement.

Beware. Math in this vid is incorrect, as others have noted. Here’s a simple way to do it correctly. The total charge in a battery is in Amp-hours (or Ah for short), not Amps as the presenter keeps saying. It is a current times the time the current is drawn. To get Amps from Amp-hours, divide the charge by time. So .6A drawn from a 17.2Ah battery will last 17.2Ah/0.6A=28.7hours. Pay attention to the units: the Amp in Amp-hours cancels the Amp in the denominator leaving Hours. Another: Want the 17.2Ah battery to last 24h. How many Amps drawn? 17.2Ah/24h. Hours cancel, leaving the Amps; it is 0.72A.

This was a good video on how to determine which replacement battery to purchase, however there are no instructions given for actually replacing the battery. Title is misleading.

I love how a video on “How to replace a home alarm battery” wasn’t actually about that, but about shilling your website’s search tool feature, and some extraneous information that no one actually cares about. You didn’t even actually show “how to replace home alarm battery”. Downvoted.

Oursaibaba says

I have changed my alarm battery, but the problem still persist, triggering the alarm once a while in couple of days, until I just press any random button.. Please help.

Matthew Pavao says

+Oursaibaba

I have this same problem as well.

Matthew Pavao says

+Matthew Pavao

Did you ever solve it?

AintBigAintClever says

Ah = amp-hours, not amps. Short out a 7Ah battery and you’ll get a damned sight more than 7 amps!

Ignoring Peukert’s law for a moment, a 7 Ah battery will put out 7 amps for 1 hour, 1 amp for 7 hours, half an amp for 14 hours, and so on.

When you brink Peukert’s law into play you find the Ah rating is typically based on 20 hours, so it’ll put out about 300mA for 20 hours. The higher the current draw, the lower the capacity (so you’ll get more than 7Ah if you draw less than 300mA, less than 7Ah if you draw more than 300mA).

Also, as zx3zx4 pointed out, the formula is wrong. Using your formula (1.39Ah per hour) results in 1.39×24 = 33.36Ah for 24 hours’ runtime, even though the panel states 17.2Ah will do. The correct multiplier to use in the formula would be 0.717Ah per hour.

Dan Hansen says

Good info to know if (like me) you inherited one of these systems when you bought the house and were not involved in the original purchase or installation. Sure, replacing a battery is not difficult, but it is nice to have the basic info about what to look for easily available.

Ite Laird says

This is one of the few videos that explains the need to pay attention to the F1 or F2 size clip. Thanks for pointing that out, so I could order the correct replacement.

Okaythen001 says

when I change the battery do I need to unplug the power? anything I shoudl watch out for?

Alarm Tech911 says

don’t let the battery terminals touch each other or the metal box. i recommend that u unplug it from the AC first

TGP Fire and Security says

+Okaythen001 Its the safest way but once you unplug the battery with the mains off, it will trigger the external siren.

Rick Baartman says

Beware. Math in this vid is incorrect, as others have noted. Here’s a simple way to do it correctly. The total charge in a battery is in Amp-hours (or Ah for short), not Amps as the presenter keeps saying. It is a current times the time the current is drawn. To get Amps from Amp-hours, divide the charge by time. So .6A drawn from a 17.2Ah battery will last 17.2Ah/0.6A=28.7hours. Pay attention to the units: the Amp in Amp-hours cancels the Amp in the denominator leaving Hours. Another: Want the 17.2Ah battery to last 24h. How many Amps drawn? 17.2Ah/24h. Hours cancel, leaving the Amps; it is 0.72A.

Barbara Harkness says

This was a good video on how to determine which replacement battery to purchase, however there are no instructions given for actually replacing the battery. Title is misleading.

stormsigma says

I love how a video on “How to replace a home alarm battery” wasn’t actually about that, but about shilling your website’s search tool feature, and some extraneous information that no one actually cares about. You didn’t even actually show “how to replace home alarm battery”. Downvoted.