Exit sign batteries
The battery keeps your exit sign lit when the power fails. Here is how to know when it is time to replace it.
Why exit signs have batteries
Illuminated exit signs must stay lit for at least 90 minutes during a power failure. Unless the building has an emergency generator or central battery system serving the signs, each sign carries its own battery that charges from normal power.
How to tell an exit sign battery is failing
- The sign goes dark or dims during the 30-second or 90-minute test
- The fault or battery indicator is on
- The battery is swollen, leaking or corroded
Replacing the battery
- Match the replacement exactly to the label: voltage, capacity, chemistry, connector.
- Disconnect power to the sign safely.
- Replace and reconnect the battery firmly.
- Restore power and allow a full charge.
- Test and record the result.
Replace the battery or the sign?
If the sign is older, uses discontinued parts, or fails tests repeatedly, a new LED sign often costs little more than a battery and labor. A self-testing One Touch exit sign also removes the monthly manual test.
Frequently asked questions
How long does an exit sign battery last?
It varies with chemistry and temperature; many last a few years. The annual 90-minute test is the reliable way to know.
Why is my exit sign beeping or showing a red light?
Many signs signal a battery, charger or lamp fault with an indicator or alarm. Check the manual for the code, then test the battery.