Hetronic CS 434 Crane Remote Replacement Battery 3.6V 2500mAh

Hetronic CS 434 / ERGO Series — 3.6V Ni-MH Replacement Battery (900)

This is a 3.6V, 2500mAh Ni-MH replacement battery for Hetronic crane remote controls. It fits the CS 434, ERGO, ERGO-F, EURO, and over a dozen additional Hetronic handheld transmitters used on overhead cranes and material handling equipment. Voltage and capacity match OEM specs (Part No. 900 / 68300520).

• CS 434 and ERGO platform fit: These remotes share a common battery bay geometry, connector pin-out, and BMS handshake protocol across the ERGO, ERGO-F, and EURO variants. One cell format covers the full range without modification.
• Bench tested on actual hardware: We cycled this cell through simulated solenoid activation sequences on the ERGO platform. The BMS held steady through repeated inrush events without triggering a protection cutoff at rated capacity.
• Monthly charge during idle periods: Hetronic remotes on seasonal or infrequent crane duty often sit uncharged for months. Ni-MH cells self-discharge at roughly 1–2% per day. Charge this battery once a month during storage to prevent the cell from dropping to a voltage level where the remote's protection circuit will refuse to accept a charge cycle.

Solenoid activation causing power dropout on a freshly installed battery

When a crane operator triggers a hoist or travel function, the remote's radio module and output relay fire simultaneously. That combined inrush current spike can trip a battery's internal protection circuit if the cell is not at full charge. A partially charged Ni-MH cell has higher internal resistance, which amplifies the voltage sag under load. The BMS reads this sag as an unsafe discharge event and cuts output. Charge the battery to full on the Hetronic cradle charger before field use — a full cell keeps internal resistance low enough to absorb the inrush without dropout.

Remote shows low battery immediately after new cell install

Ni-MH cells ship and store at roughly 40–60% of rated voltage — this is intentional to slow self-discharge during transit. When the remote reads this storage voltage on first boot, it correctly flags it as a low-battery condition. The cell is not faulty. Connect the battery to the Hetronic charger before inserting it into the remote. Charge until the charger indicator confirms a full cycle, then install — the low-battery warning will not appear at 3.6V nominal.