Dorma Kaba 79 Replacement Battery 2.4V 2700mAh

Dorma Kaba 79 / Kaba 790 Locks — 2.4V Ni-MH Replacement Battery (PA000497)

This is a 2.4V, 2700mAh Ni-MH rechargeable battery for the Dorma Kaba 79 and Kaba 790 cylindrical electronic door locks. These locks are common in commercial and institutional access control installations. The PA000497 replaces the original internal power cell that drives the locking mechanism and electronics.

• Kaba 79 and Kaba 790 compatibility: Both lock families share the same 2.4V internal power architecture, connector footprint, and BMS handshake requirements — a single cell format covers both platforms without modification.
• Bench tested on actual hardware: We cycled this battery through charge and discharge on a Kaba-platform test rig. The BMS accepted the cell without fault codes, and the lock motor engaged cleanly at rated voltage throughout the cycle.
• Post-swap access verification: After fitting this battery, test every enrolled credential — keycard, PIN, or fob — before closing the door. Kaba 79-series locks sometimes require a brief firmware handshake after power interruption before all access methods are fully active again.

Why the Kaba 79 lock motor feels sluggish or slow after a battery replacement

A freshly installed Ni-MH cell can sit at storage voltage — typically around 2.2V or lower — rather than its nominal 2.4V. The Kaba 79 motor draws a short high-current burst to retract the bolt, and an undercharged cell sags under that load. The result is a slow or incomplete throw that feels mechanical but is actually electrical. Put the lock on charge immediately after installation and allow a full charge cycle before relying on the lock for access control duties.

Low-battery warning persists immediately after fitting a new PA000497

The Kaba 79 reads cell voltage on power-up and flags anything below its low-battery threshold — usually around 2.1V. A Ni-MH cell shipped in storage state can read below that threshold before its first charge. This is not a faulty battery. Connect the lock to its charging source, allow the cell to reach full charge, then perform a hard power cycle by removing and reinserting the battery. The warning should clear once the lock reads a resting voltage at or above 2.4V.