About this replacement
Cavotec M9-1051-3600 EX / MC-3000 Series — 7.4V Li-ion Replacement Battery (M5-1051-3600)
This is a 7.4V 2600mAh Li-ion battery for the Cavotec M9-1051-3600 EX, MC-3, and MC-3000 wireless crane remote controls. These remotes operate overhead cranes and hoists in industrial environments where a dead battery means halted lifts and delayed work. Voltage and capacity match the OEM specification exactly.
- MC-3 and MC-3000 platform fit: The M9-1051-3600 EX, MC-3, and MC-3000 share the same 7.4V two-cell architecture, connector pinout, and BMS handshake protocol — one battery covers all three variants without modification.
- Bench tested on actual hardware: We cycled this battery through full charge and discharge on a Cavotec MC-3000 remote. The BMS initialised cleanly, cell balancing engaged correctly, and the protection circuit held steady under solenoid activation inrush without tripping.
- Monthly charge during idle periods: Crane remotes often sit unused for weeks or months between jobs. Li-ion cells discharged below 2.5V per cell trigger BMS deep-discharge lockout. Connect the charger for at least 30 minutes once a month, even when the remote is not in active use, to keep cells above that threshold.
Solenoid activation causing power dropout on a freshly installed battery
When a crane remote fires a solenoid or relay, the inrush current can spike sharply for 20–50 milliseconds. If the battery's BMS has a low overcurrent threshold — common in cells at partial charge — this spike trips the protection circuit and cuts power to the remote. The dropout looks like the remote restarting or going blank mid-command. Charge the battery fully before first operational use; a cell sitting at storage voltage (around 3.7V per cell) has less headroom to absorb that inrush without tripping the BMS.
Remote showing low battery indicator immediately after new cell install
Replacement Li-ion batteries ship at storage voltage — typically 3.6–3.8V per cell, or roughly 50–60% state of charge. The MC-3000 remote reads cell voltage directly and flags anything below its low-battery threshold as a warning, even on a brand-new pack. This is not a fault with the battery. Connect the battery to the Cavotec charger and run a full charge cycle before use — the low-battery indicator should clear once both cells reach 4.1–4.2V each.