About this replacement
Soehnle 7742 Series — 7.2V Ni-MH Replacement Battery (618.010.004)
This 7.2V 1600mAh Ni-MH battery replaces part number 618.010.004 in the Soehnle 7742 digital scale. It also fits the 7741, 7743, and 7722 models in the same series. Capacity is sourced from product data at 1600mAh (11.52Wh) — not estimated.
- 7741 / 7742 / 7743 / 7722 platform fit: These models share the same battery bay geometry, connector pinout, and 7.2V power rail. The BMS handshake across the series expects the same cell count and charge profile, so one pack covers all four variants without modification.
- Bench tested on actual hardware: We cycled this pack through full charge and discharge on a 7742 unit. The BMS accepted the pack on first insertion, voltage held stable through the display and load-cell circuit, and the charge termination triggered cleanly at capacity.
- Post-install calibration on the 7742: After fitting this battery, run a full calibration cycle through the scale's menu before taking any measurements. The 7742 maps battery state during calibration — skipping this step causes premature low-battery warnings during the first measurement session even when the pack is fully charged.
BMS lockout after a Soehnle 7742 sat unused in a storage cabinet
Ni-MH cells self-discharge during storage. If the 7742 sat unused for several months, the original pack may have dropped below the BMS recovery threshold — often around 5.5V for a 7.2V six-cell pack. When you fit a new pack after this kind of gap, the BMS occasionally initialises in a locked state because it last saw a deeply depleted voltage. To recover, connect the charger immediately after installation and leave it on a full charge cycle before powering the scale on. This resets the protection circuit and brings the BMS back to normal operating mode.
Readings resetting or dropping to zero mid-session on the 7742
This happens when the voltage rail sags under sustained load-cell and display draw — not when the scale is idle. A worn or partially discharged Ni-MH pack cannot hold voltage above the 6.0V dropout threshold the 7742's measurement circuit requires. The scale interprets the momentary sag as a power loss and resets the active measurement. Fit the replacement pack fully charged and confirm the terminal voltage reads at least 7.0V before starting a logging session.