About this replacement
Ikusi TM61 Transmitters — 7.2V Ni-MH Replacement Battery (BT06)
This is a 7.2V, 600mAh Ni-MH replacement battery for Ikusi crane remote control transmitters. It fits the TM60, TM61, TM62, and related transmitter models used on industrial cranes and lifting equipment. Sourced to match the original BT06 specification, including connector and cell count.
- TM60 / TM61 / TM62 transmitter compatibility: These models share a common 7.2V battery bay, connector pinout, and BMS handshake protocol. A six-cell Ni-MH pack at this voltage slots directly into the same charge circuit across the range without firmware changes.
- Bench tested on actual hardware: We cycled this pack through charge, standby, and solenoid-activation load tests. The BMS held steady through the inrush current spike at relay engagement — no dropout, no fault codes.
- Monthly charge during idle periods: Crane remotes can sit unused for weeks. Ni-MH cells lose charge in storage and can drop below a recoverable threshold. Run a charge cycle at least once a month during any idle period to keep the pack above that floor.
Why the TM61 loses power the moment a solenoid or relay fires
Solenoid activation draws a sharp inrush current — often three to five times the steady-state load — lasting only milliseconds. A battery with degraded cells or low state of charge can't sustain the voltage rail through that spike. The transmitter's internal voltage monitor sees a sag below its cutoff threshold and drops the output. This isn't a transmitter fault; it's a pack capacity issue. A fully charged, healthy cell set handles the surge without a dropout.
Remote shows low battery indicator immediately after fitting a new pack
New Ni-MH cells ship at storage voltage — typically 1.0V to 1.1V per cell, well below the 1.2V nominal. At six cells, that puts the pack below the transmitter's "low battery" threshold from the first power-on. The fix is straightforward: place the transmitter on charge before first use and run a full charge cycle. Once cells reach nominal voltage, the indicator clears. Do not judge the pack's capacity until it has completed at least one full charge from storage.