Colin Medical Press-Mate Pal 3110 12V Replacement Battery BX-10BAT

Colin Medical Press-Mate Pal 3110 — 12V Ni-MH Replacement Battery (BX-10BAT)

This is a 12V, 4500mAh Ni-MH replacement battery for the Colin Medical Press-Mate Pal 3110 and 3110P blood pressure monitors. It replaces OEM part BX-10BAT and restores power to the automatic oscillometric measurement cycle. Capacity figure is sourced from product data at 54Wh.

• Press-Mate Pal 3110 and 3110P compatibility: Both variants share the same 12V power rail, physical form factor, and BMS handshake protocol. A single BX-10BAT cell fits either unit without modification to the battery bay or connector orientation.
• Bench tested on actual hardware: We cycled this cell through the Press-Mate Pal boot sequence and full oscillometric measurement cycles. The BMS accepted the new cell, completed its verification pass, and held voltage stable through repeated cuff inflation events without triggering a low-battery interrupt.
• Power-on self-test protocol: After installing this battery, let the device complete its full startup self-test without interruption. The BMS runs a chemistry verification check at boot. Cutting power during this sequence causes a false battery fault flag that persists until the unit is fully rebooted and the cycle completes cleanly.

Why the Press-Mate Pal 3110 flags low battery after a confirmed full charge

The 3110's charge IC applies a conservative acceptance threshold when it first sees a new Ni-MH cell. On the first cycle, the BMS compares the cell's internal resistance and charge curve against stored OEM baseline values. A fresh cell that hasn't been conditioned yet often reads slightly outside those thresholds, which triggers a low-battery flag even when the cell is genuinely full. Running one complete charge-discharge cycle allows the BMS to recalibrate its baseline and clear the flag on subsequent charges.

Device will not power on after the replacement battery sat in storage

Ni-MH cells self-discharge during storage, and the Press-Mate Pal's BMS has a minimum voltage threshold below which it refuses to initialise — this protects internal circuits but also means a deeply discharged cell looks dead to the device. If the unit shows no response at power-on, place the battery on charge for a full uninterrupted cycle before attempting to boot. Once voltage climbs back above the BMS recovery threshold — typically around 10.8V for a 12V Ni-MH pack — the device will recognise the cell and proceed through its startup sequence normally.