HP M1758A PageWriter 12V Replacement Battery 4500mAh

HP M1758A PageWriter ECG — 12V Sealed Lead Acid Replacement Battery (B10782)

This 12V 4500mAh sealed lead acid battery fits the HP PageWriter M1758A, M1722A, M1722B, M1723A, and related electrocardiograph models used in clinical cardiac diagnostics. It replaces OEM part numbers B10782, MLA1758, and OM10782. Voltage and chemistry match the original specification exactly — no modifications required at installation.

• PageWriter M1758A and M1722 series compatibility: These ECG models share the same 12V sealed lead acid power architecture, connector footprint, and BMS communication protocol. A battery meeting the original voltage and chemistry spec slots into any unit in this family without adapter or firmware change.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the M1758A platform. The BMS accepted the battery, completed its internal verification sequence, and held voltage above the low-battery threshold through repeated test loads replicating a clinical ECG acquisition session.
• Post-installation self-test protocol: After fitting this battery, allow the PageWriter to complete its full power-on self-test without interruption. The device BMS runs a chemistry verification at startup — cutting power mid-sequence stores a false battery fault that persists until the next complete reboot cycle.

Why the PageWriter M1758A alarms low battery immediately after a confirmed full charge

The M1758A BMS compares the incoming cell's voltage response against a threshold calibrated to a fully cycled OEM cell. A new sealed lead acid cell has a slightly different internal resistance profile in its first few cycles, which causes the BMS to read capacity as lower than actual. This is not a fault with the battery — it is the BMS applying a conservative threshold to an unconditioned cell. Run one complete charge-discharge cycle through the device before treating any low-battery alarm as valid.

PageWriter ECG will not power on after the replacement battery sat in storage

Sealed lead acid cells self-discharge during storage. If the cell drops below approximately 10.5V, the M1758A BMS enters a protection state and blocks startup to prevent drawing the cell into deep discharge damage. Connect the device to mains power and leave it on charge for a minimum of 12 hours before attempting to power on. If the device still does not start, check terminal voltage at the battery contacts — a reading below 10V indicates the cell requires a recovery charge from a compatible SLA charger before the onboard charger will engage.