About this replacement
Trismed Cardipia 400 Series — 19.2V Ni-MH Replacement Battery (16HR-406NH)
This is a 19.2V, 2000mAh Ni-MH battery that replaces part number 16HR-406NH in the Trismed Cardipia 400, 400H, 406NH, and 406RH portable cardiac monitors. These devices run continuous ECG and vital sign monitoring in clinical wards and home care environments. The battery slots into the monitor's internal bay and powers the unit during unplugged patient sessions.
- Cardipia 400 series fit: The 400, 400H, 406NH, and 406RH share the same 19.2V battery bay and connector pinout. The BMS on each model communicates over the same handshake protocol, so one cell pack serves the full line without modification.
- Bench tested on actual hardware: We cycled this battery through charge and discharge on the Cardipia platform. The BMS accepted the cell, cleared startup self-test, and held voltage within spec across the full load profile of the monitor.
- Post-swap startup protocol: After installing this battery, allow the Cardipia to complete its full power-on self-test without interruption. The device runs a BMS verification sequence at boot — cutting power during this window triggers a false battery fault that persists until the next clean reboot.
Cardipia 400 not completing its boot sequence after a battery swap
The Cardipia 400 runs a multi-stage power-on self-test that includes a BMS verification check. If the battery voltage sits at the low end of the accepted range — common after shipping or shelf storage — the monitor may stall mid-boot or return a battery error and refuse to proceed. The fix is to charge the replacement battery fully before inserting it, then power on the device while it remains connected to mains. Once the self-test completes cleanly on mains power, the monitor will recognise the battery and resume normal operation. Target a resting cell voltage of at least 20.4V before attempting a standalone boot.
Charge indicator not reaching 100% on the first charge cycle
On first charge, the Cardipia's charge IC applies a conservative current limit to an unfamiliar cell, which can cause the indicator to plateau at 85–95% and stop climbing. This is a charge algorithm behaviour, not a faulty battery. Run one complete charge-to-discharge-to-charge cycle and the IC recalibrates its capacity estimate. After that first conditioning cycle, the indicator will reach 100% and the reported capacity will align with the 2000mAh rating.