Fluke 932645 Thermal Imager Replacement Battery 10.8V 3600mAh

Fluke 932645 — 10.8V Ni-MH Replacement Battery (255112)

This is a 10.8V, 3600mAh Ni-MH battery for the Fluke 932645 thermal imager. It replaces OEM part number 255112 and fits directly into the 932645 battery bay. This imager is used for building envelope surveys, electrical panel inspections, and HVAC diagnostics where field uptime matters.

• Fluke 932645 compatibility: The 932645 draws a stabilised 10.8V rail to power both the IR sensor array and the onboard image processor simultaneously. This pack matches that rail exactly — voltage, connector, and BMS communication handshake all align with what the instrument expects at power-on.
• Bench tested on actual hardware: We ran this pack through the 932645's full power-on sequence, including IR sensor initialisation and a live imaging session. The BMS held stable through the current spike at sensor warm-up and did not trip during sustained imaging load.
• First-use calibration step: After installing this pack, run a full calibration cycle through the instrument menu before deploying to the field. The 932645 maps battery state during calibration — skipping it causes premature low-battery warnings during your first measurement session.

BMS cutoff during IR sensor initialisation on the 932645

The 932645's IR sensor array draws a sharp current spike during the first two seconds of warm-up. An aged or deeply discharged Ni-MH pack may sag below the BMS protection threshold during this spike, causing an immediate shutdown before imaging begins. This is a BMS trip, not a failed battery — the pack voltage recovers but the instrument has already cut power. To clear it, let the pack sit on charge for a full cycle, then power the imager on with the lens cap on so the sensor initialises at minimal load before switching to live view.

932645 displaying inconsistent battery percentage after reboot

When a new Ni-MH pack replaces an old one, the 932645's battery indicator recalibrates its voltage-threshold map over the first few discharge cycles. During this period, the percentage readout may jump or reset on reboot — this is the instrument re-learning the new pack's discharge curve, not a fault. Ni-MH cells also have a flatter discharge curve than Li-ion, which makes voltage-based percentage estimates less precise until the threshold map settles. Run two to three full charge-discharge cycles through the instrument and the readout will stabilise.