picture of 4 different types of CPU batteries

What Happens to my Security System When the Power Goes Out?

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With several summer storms, we’ve received many calls from customers with security system battery issues. We’ll answer some common questions about what happens to your security system when the power goes out.

picture of 4 different types of CPU batteries

1. ls my alarm system functional?

Yes! All alarm systems have a source of back-up power. That back-up power will have at least 4 hours of standby power for the system. In most cases, the back-up power will last 24 hours. Based on recent reports from power outages, some systems have had back-up power last as long as 2 days.

The back-up battery should be changed every 3-5 years. This is due to the fact that the alarm system is always charging the battery. At the 5 year point, the battery will not store a full charge.

2. What happens if I don’t change the battery after 5 years?

When the power goes out in that situation, the system will go on back-up power and possibly last only an hour instead of 24 hours. When the power returns, the battery will recharge.

3. How do I change the battery?

First, locate the battery which is located with the main processor. The terminals just slide off the post. To remember when the battery was changed, we recommend writing the month and year on the battery with a permanent marker.

  • If you have a Simon or Lynx system, the battery is in the main keypad. You need to power down the system then repower with battery first then AC power.
  • If you have a Caddx, Ademco, DSC, or First Alert system, the battery is located in the enclosure and not in the keypad. This enclosure is usually located in a remote room such as a utility closet or mechanical room. Replace the battery red to red and black to black.

The low battery alert should clear in 4-12 hours. If it does not clear, try arming and disarming the system or review the status. If it still hasn’t cleared after 12 hours, call us and speak with a service representative.

4. Where do I get a battery?

There are many battery stores in metropolitan areas. Check your local fleet farm store and in some cases an auto parts store can order a battery for you. Look on the battery for the voltage (V) and the amp hour rating (AH) and give this to the representative looking for your battery. Online stores or Heartland Security can also ship the battery to your door step.

When in doubt, call us for more details about your system. Consider a service call. It might be a good idea for Heartland Security to do a full system test while replacing the battery.

Testing your security system is a valuable exercise. Unplug the power and see if the battery is working. Test the devices in your house that are on the alarm system. A good battery could mean the difference between your house freezing up in the winter, a fire being detected, or a burglary event being notified. Be proactive and change your CPU battery every 5 years or sooner.