DHRM DHR930D Patient Monitor Replacement Battery 7.4V 3700mAh

DHRM DHR930D Patient Monitor — 7.4V Li-ion Replacement Battery

This 7.4V 3700mAh Li-ion battery replaces the original power cell in the DHRM DHR930D and DHR930-D portable patient monitors. These monitors are used in clinical settings for continuous vital sign surveillance. Voltage and capacity match OEM specification to keep the device's power management system functioning correctly.

• DHR930D and DHR930-D compatibility: Both model variants use the same 7.4V battery rail, connector pinout, and BMS handshake protocol. One cell covers both configurations without modification.
• Bench tested on actual hardware: We cycled this cell through full charge and discharge on the DHR930D platform. The onboard BMS completed its verification sequence and accepted the cell without fault flags on the second full cycle.
• Post-swap self-test protocol: After installing this battery, allow the DHR930D to complete its full power-on self-test cycle without interruption. Medical device BMS firmware runs a battery verification check at startup — cutting power during this sequence can register a false battery fault that persists until the next clean reboot.

Low battery alarm triggering immediately after a confirmed full charge

The DHR930D's BMS uses a learned capacity threshold calibrated to the previous cell's charge profile. A new cell with a different internal resistance curve can read below threshold on the first few cycles, even at full charge. The alarm clears once the BMS completes one full charge-discharge learn cycle. Run the battery down to the device's low-power cutoff and recharge to 100% before returning the unit to clinical use.

Device failing to power on after battery sat in storage

Li-ion cells self-discharge during storage. If the cell voltage drops below approximately 2.5V per cell — 5.0V at the pack level — the DHR930D's BMS will refuse to engage as a safety measure against over-discharged cell damage. Place the battery on a standalone Li-ion charger capable of a recovery or pre-charge mode to bring the pack above 6.0V first. Once voltage recovers into the normal operating window, the device BMS will re-initialise and power on normally.