About this replacement
Indexa RZ03 — 12V Ni-MH Replacement Battery (AKKU-RZ03A)
This is a 12V 700mAh Ni-MH battery for the Indexa RZ03 automatic door opener. It slots into the door controller and provides backup power to the control system when mains supply is interrupted. Without a functional backup battery, the automatic door mechanism loses power and the controller may lose its programmed settings.
- RZ03 controller fit: The RZ03 backup circuit runs on a dedicated 12V Ni-MH rail. This battery matches that rail and connects through the OEM-spec connector, so the BMS handshake completes and the controller accepts it as a valid power source.
- Bench tested on actual hardware: We ran this battery through a simulated mains-failure cutover on the RZ03 controller. The BMS handed over cleanly, the door completed a full open-and-close cycle, and the controller retained its programmed settings throughout.
- Post-install load test: After installing the backup battery, manually trigger a power-fail test during a low-traffic period. The RZ03 backup battery must be tested under actual load at installation — a full door cycle draw is the only way to confirm the battery is functional before you need it.
Door controller losing stored programming after a power outage
The RZ03 stores its door timing, force, and access settings in volatile RAM. That RAM is held by the backup battery when mains power drops. A depleted or failed backup battery cannot sustain the RAM, so all programmed parameters reset to factory defaults the moment mains power is lost. After swapping the battery, allow a full 24-hour charge before the next expected power interruption to ensure the battery can sustain the RAM under real outage conditions.
Automatic door not completing the full open cycle on battery backup
If the door stalls or reverses mid-cycle during a mains failure, the backup battery is likely voltage-sagging under motor-start load. Ni-MH cells at partial charge drop sharply when the door motor draws its startup current, which triggers the BMS low-voltage cutoff before the cycle finishes. A fully charged battery should hold above 10.8V through the motor-start surge on the RZ03. Charge the replacement for 24 hours before testing, then verify the door completes a full unassisted cycle.