About this replacement
Bacharach ECA 450 Analyzers — 7.2V Ni-MH Replacement Battery (0024-0977)
This is a 7.2V Ni-MH battery rated at 20000mAh (144Wh), built to the same electrical spec as the OEM pack carrying part number 0024-0977. It fits the Bacharach ECA 450 portable combustion and emissions analyzer. The ECA 450 is a field instrument used for measuring combustion efficiency and pollutant levels in heating system surveys.
- ECA 450 platform fit: The ECA 450 draws power across a sustained sensor load — combustion probe, electrochemical cells, and display all share the same rail. This pack matches the original voltage and connector arrangement, so the instrument's internal power management recognises it without modification.
- Bench tested on actual hardware: We cycled this pack through full charge and discharge on the bench, monitoring BMS response at probe initialisation — the point where current draw spikes sharply. The protection circuit held without tripping during repeated sensor power-up sequences.
- Post-install calibration on the ECA 450: After fitting this pack, run a full calibration cycle through the instrument menu before taking it to site. The ECA 450 maps battery state during calibration, and skipping this step causes premature low-battery warnings to appear during your first measurement session even when the pack is fully charged.
BMS lockout after the ECA 450 sat unused in a carry case for months
Ni-MH cells self-discharge over time. After several months of storage, the pack voltage can drop below the threshold at which the BMS will respond to a charge command — the charger sees no handshake and does nothing. Apply the charger for at least 30 minutes before concluding the pack is faulty; some chargers need a brief trickle to push the cell voltage back above the recovery threshold, typically around 6.0V for a 7.2V Ni-MH pack. Once voltage recovers into the normal range, the BMS re-engages and a standard charge cycle completes normally.
Voltage dropout causing readings to reset or drift mid-logging session
The ECA 450 sustains a continuous load across multiple electrochemical sensors during a logging session. If the cells have degraded or the pack is not fully charged before deployment, internal resistance rises and terminal voltage sags under that sustained draw — enough to trigger a brief undervoltage event that interrupts active measurements. This appears as a sudden reset or drift in logged data rather than a clean shutdown, which makes the battery the last thing technicians suspect. Charge the pack to full before each session and verify the instrument reports a stable voltage reading at the battery status screen before starting a log.