About this replacement
Fresenius Injectomat 500 Series — 6V Ni-MH Replacement Battery (125-00-455100032)
This is a 6V, 2000mAh Ni-MH replacement battery for the Fresenius Injectomat 500 and Injectomat 500D infusion pumps, as well as the MCM Agilia 500 and MCM Agilia 500D. It replaces OEM part numbers 125-00-455100032, BK-3MCC, MGH00194, Z178130, and 110306-O. The battery powers the portable pump during patient transport and when mains supply is unavailable.
- Injectomat 500 and MCM Agilia 500 platform fit: Both the Injectomat and MCM Agilia 500 series share the same 6V battery compartment, connector pinout, and BMS handshake protocol — one cell pack covers all variants in this family.
- Bench tested on actual hardware: We ran this cell through charge acceptance and load draw testing. The BMS completed full charge handshake, and the protection circuit responded correctly to simulated over-discharge conditions without tripping a hard fault.
- Post-installation self-test protocol: After fitting this battery, allow the Injectomat to complete its full power-on self-test cycle without interruption. The device runs a BMS verification sequence at startup — cutting power during this window flags a persistent battery fault that won't clear until the next complete reboot.
Self-test failure after battery swap on the Injectomat 500
The Injectomat 500 runs a BMS learn cycle on first installation to characterise the new cell's internal resistance and charge acceptance curve. A fresh Ni-MH cell straight from packaging has not yet completed this cycle, so the device may flag a battery fault even when the cell is fully charged. One complete charge-discharge cycle lets the BMS calibrate its thresholds to the new cell. Until that cycle completes, do not use the pump in an unmonitored clinical setting.
Charge indicator stalling below 100% on the first charge
The Injectomat's charge IC applies a conservative current limit when it detects elevated internal resistance on a new or storage-aged Ni-MH cell. This causes the charge indicator to plateau well below full and can trigger a premature charge-complete signal. The fix is to run one full charge cycle, allow the pump to discharge normally in use, then recharge to 100%. After this conditioning cycle, the charge IC recalibrates and the indicator reads accurately. Confirm the cell has reached at least 6.0V open-circuit before returning the pump to service.