Z200045-6-200 Ambix Activ Ambulatory Pump Replacement Battery 4.8V

Ambix Activ Ambulatory Pump — 4.8V Ni-MH Replacement Battery (Z200045-6-200)

This is a 4.8V, 1200mAh Ni-MH battery for the Ambix Activ Ambulatory Pump. It replaces OEM part Z200045-6-200. The Activ is a portable infusion pump used in clinical and home care settings to deliver medication or nutrition continuously or intermittently via IV.

• Activ Ambulatory Pump fit: The Activ uses a 4-cell Ni-MH pack at 4.8V nominal. The BMS on this device communicates with the pack during every charge cycle and power-on self-test. A replacement must match cell count, voltage, and connector pinout exactly — this battery does.
• Bench tested on actual hardware: We ran this battery through full charge-discharge cycles and monitored BMS handshake behaviour at startup. The pack passed the device's self-test sequence and held stable voltage under the pump's continuous-draw load profile without triggering a fault alarm.
• First-use cycle on a medical infusion pump: After installing this battery, let the Activ complete its power-on self-test without interruption. The device's BMS runs a verification routine at startup — cutting power during this window causes a persistent false battery fault that won't clear until a full reboot and completed self-test cycle.

Why the Activ Ambulatory Pump alarms low battery immediately after a confirmed full charge

The Activ's charge IC uses a delta-V cutoff to detect full charge on Ni-MH cells. A new replacement cell has a slightly different charge acceptance curve than an aged OEM cell, so the charger may terminate early or the BMS may flag the pack as below threshold on first use. This is a BMS learn-cycle issue, not a faulty battery. Run one complete charge-discharge cycle on the device before clinical deployment. After that first cycle, the BMS recalibrates its threshold and the alarm clears.

Activ Pump not completing boot sequence after battery swap

If the replacement cell sat in storage for several months, self-discharge may have pulled the pack voltage below the Activ's BMS recovery threshold — typically around 3.6V for a 4-cell Ni-MH pack. At that level, the device cannot draw enough power to finish its boot sequence and halts mid-startup. Place the battery in a compatible external Ni-MH charger first and bring it to at least 4.2V before inserting it into the pump. Once voltage is above the recovery floor, the Activ boots normally and the self-test completes.