About this replacement
Hetronic ERGO-120 — 3.7V Li-Polymer Replacement Battery (68303650)
This is a 3.7V 3000mAh Li-Polymer replacement battery for the Hetronic ERGO-120 industrial crane and hoist remote control. It matches OEM part number 68303650 and fits directly into the ERGO-120 transmitter housing. Capacity is rated at 11.1Wh from the product specification.
- ERGO-120 transmitter fit: The ERGO-120 uses a single-cell Li-Polymer pack at 3.7V nominal. The BMS in this unit monitors cell voltage and cuts output if the pack drops below threshold during active crane operation. This replacement matches that voltage rail and connector orientation so the transmitter BMS accepts the pack without error codes.
- Bench tested on actual hardware: We cycled this battery through full charge and discharge on a load bench simulating ERGO-120 draw patterns. The BMS engaged correctly at low-voltage cutoff, and charge acceptance was normal across multiple cycles with no cell swelling.
- Monthly charge during idle storage: Crane remotes often sit unused for weeks between jobs. Connect this battery to a charger for at least 30 minutes once a month during idle periods — Li-Polymer cells discharged below 2.5V enter deep-discharge BMS lockout and will not recover even when a charger is plugged in.
Power dropout on the ERGO-120 during solenoid or relay activation
When a crane solenoid fires, the inrush current spike can briefly exceed what a degraded or partially charged battery pack can sustain. The ERGO-120 BMS interprets this voltage sag as an undervoltage condition and trips the output to protect the cell. This dropout causes the remote to lose signal mid-operation, which can trigger an unintended E-stop on the crane. Starting each shift with a fully charged pack at 4.2V keeps the cell voltage above the BMS trip threshold during those inrush spikes.
ERGO-120 showing low battery warning immediately after installing a new cell
A new Li-Polymer cell ships at storage voltage — typically around 3.6–3.8V — not at full charge. The ERGO-120 firmware reads cell voltage at startup and flags anything below its low-battery threshold as a warning. This is not a fault with the replacement pack. Connect the battery to the charger and bring it to 4.2V before the first use, and the warning will clear.