About this replacement
Hetronic ERGO-S — 3.7V Li-ion Replacement Battery (68303700)
This is a 3.7V, 3400mAh Li-ion battery for the Hetronic ERGO-S wireless crane and hoist remote control system. It replaces OEM part number 68303700. The ERGO-S is a handheld industrial remote used to operate overhead cranes and hoists from a safe distance on the work floor.
- ERGO-S platform fit: The ERGO-S uses a single-cell 3.7V Li-ion pack with a dedicated BMS that manages cutoff thresholds for the radio module and relay outputs. This replacement cell matches the same voltage rail and connector orientation, so the remote's onboard BMS communicates correctly without false low-battery flags.
- Bench tested on actual hardware: We ran this cell through the ERGO-S power-on sequence and confirmed BMS handshake, radio link acquisition, and relay activation without voltage dropout. Cell voltage held stable under the brief inrush current spike that solenoid outputs produce.
- Idle-period charge discipline: Crane remotes sit unused for weeks or months between jobs. Charge this battery once a month during idle periods — Li-ion cells discharged below 2.5V enter deep-discharge BMS lockout and will not respond to a charger even when connected.
Solenoid activation causing power dropout on a fresh battery
When an ERGO-S remote fires a crane relay or solenoid output, the inrush current spike is brief but sharp. A cell at storage voltage — typically around 3.6V — can sag enough under that load for the BMS to trigger an undervoltage cutoff, dropping the remote mid-command. This is not a fault with the battery or the remote. Fully charge the replacement cell before the first use. A cell at 4.1–4.2V handles the inrush without sagging past the BMS threshold.
Remote showing low battery immediately after a cell swap
A newly installed cell shipped at storage voltage — roughly 3.5–3.6V — reads as low battery on the ERGO-S display because the remote's charge indicator maps to resting cell voltage. The cell is not faulty; it simply has not been charged since leaving the warehouse. Connect the remote to its charger and bring the cell to full charge before dismissing this as a battery defect. Once the cell reaches 4.1V or higher, the low-battery indicator will clear.