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How to Replace your Alarm Batteries

How to Replace your Alarm Batteries

You’re doing the right thing by protecting your prized possessions including your loved ones with an alarm system. Having proven to have prevented many burglaries and home invasions through the years, that extra peace of mind you get by having a security system is worth its weight.

Some alarm systems are hard-wired to the house with a backup alarm battery in case the power goes out (or is cut) while others run strictly off battery power. Alarm companies generally do a great job setting up and responding in case there is an incident but something out of their typical wheelhouse is ongoing maintenance. We’ve heard of alarms going off spontaneously or sometimes not even working due to a bad battery, a drained battery or an old backup battery. False alarm can be more than a nuisance but a non-working battery can be downright dangerous.

What can you do to ensure better alarm battery system performance?

Replace the battery regularly or have a backup on standby

Should You Do it Yourself or go through the Alarm Company?

Depending on your alarm company, asking them to come out and check or replace your batteries can incur a fee. Not only could the visit cost you but the battery itself can cost upward of $120 for a battery we sell for $15.

How Often Should You Replace your Alarm System Battery?

To be on the safe side, we suggest updating every 3 to 5 years. Even though battery technology continues to evolve, given the importance of having a working alarm system the cost is minimal and the risk vs. cost isn’t worth it.

How Do You Know What Battery to Get?

Your current alarm battery most likely has a model number plus some additional information that could be useful. Check on the battery for a number. Our example shows a CA1240

Battery model number CA1240

It also includes some additional information which may be useful: 12V (you’ll want to match this, it represents the number of volts). 4AH means 4 amperes which is the total amount of charge a battery can deliver in an hour. General rule here is that there is minimal difference between 4Ah and 5Ah but the size and dimensions will remain the same so it will easily fit in the casing.

So to look for our battery that matches, we head to and do a search for “CA1240”. The top results also match the brand of our old one:

BatteryClerk search

At $13.29 you’re looking at a quarter of the price from most alarm companies and half that of the manufacturer.

How Do You Switch the Batteries?

Obviously the method for switching batteries varies from service to service but generally it’s pretty straightforward.

1. Most alarm system will have a test mode or similar which will prevent any false alarms. You can typically do this through the control panel.

2. Locate your system panel (often in the basement or closet)

alarm system control panel

3. Open up the panel door and locate the current battery. Make a note of where the current cables are attached to the terminals.

4. Switch the cables from the current battery to the new battery and place carefully back in the system panel.

Alarm battery wiring

alarm battery connection

Now you can turn off test mode and that’s pretty much all that needs to be done to ensure your peace of mind and to maintain the security of your home. Browse our current selection of replacement alarm batteries at BatteryClerk to find your match.

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