About this replacement
Fukuda Cardisuny C120 — 9.6V Ni-MH Replacement Battery (HHR-16A8W1)
This is a 9.6V, 2000mAh Ni-MH replacement battery for the Fukuda Cardisuny C120 portable ECG machine. It fits the ECG Cardisuny C120 and ME Cardisuny C120 variants. OEM part number is HHR-16A8W1.
- C120 platform compatibility: The ECG and ME Cardisuny C120 variants share the same 9.6V battery rail, connector housing, and BMS handshake protocol — one battery covers both units without modification.
- Bench tested on actual hardware: We cycled this battery through the C120's charge and discharge sequence. The BMS accepted the cell, completed its verification handshake, and held voltage within the expected operating window across all test cycles.
- Post-installation self-test requirement: After fitting this battery, let the C120 complete its full power-on self-test without interruption. The device runs a BMS verification routine at startup — cutting power during this sequence triggers a false battery fault that sticks until the next clean reboot.
C120 not completing boot sequence after battery swap
The Cardisuny C120 runs a multi-stage BMS verification during boot. A new Ni-MH cell fresh from storage may sit at a resting voltage slightly below the threshold the BMS expects to see at the start of that sequence. The device interprets this as a fault and halts before the ECG interface loads. Charge the battery fully on the C120 charger first, then power on — this brings resting voltage to the level the boot routine requires.
Low battery alarm triggers immediately after a confirmed full charge
This happens on the first one to three cycles with a new Ni-MH cell. The C120's BMS compares internal resistance and voltage recovery against a stored OEM chemistry profile. A new cell hasn't been conditioned yet, so its recovery curve doesn't match the profile threshold — the alarm fires even though capacity is present. Run one complete charge and discharge cycle before clinical use. After that cycle, the BMS re-evaluates the cell and the alarm clears at normal charge levels.