Ridgid Micro CA-300 Replacement Battery 3.6V 5200mAh

Ridgid Micro CA-300 Inspection Camera — 3.6V Li-ion Replacement Battery (990596)

This is a 3.6V, 5200mAh Li-ion battery replacement for the Ridgid Micro CA-300 Inspection Camera. It fits models 40798 and 37888 and matches OEM part numbers 990596 and 990514. Capacity figure is taken directly from product data — 18.72Wh total.

• CA-300 platform compatibility: The CA-300, 40798, and 37888 all share the same 3.6V single-cell Li-ion architecture and battery connector format. The BMS on each unit expects the same charge profile and cutoff voltage, so one cell fits the whole family without modification.
• Bench tested on actual hardware: We ran this cell on a CA-300 unit under combined display and thermal detector load. The BMS accepted the charge cycle without faults, held voltage through a full inspection simulation, and triggered the low-battery flag at the expected threshold — not earlier.
• Thermal detector warm-up after swap: After fitting a new battery, power the CA-300 on and wait 60 seconds before taking any readings. The thermal detector needs the internal electronics to reach a stable temperature before it can establish an accurate baseline calibration. Starting measurements immediately after power-on will produce drift in the first readings.

Thermal accuracy affected at low battery on the CA-300

The CA-300's thermal detector is voltage-sensitive. As the cell drops toward 3.0V under combined display and detector load, the detector's heating element loses stable current and the temperature readings begin to drift — sometimes by several degrees — before the low-battery indicator even triggers. This is not a lens or software fault. Keeping the cell above 3.2V under load is what keeps readings within spec. Swap the battery when you notice measurement inconsistency, not just when the indicator appears.

CA-300 shutting down mid-inspection despite showing charge

The shutdown is a BMS protection trip, not a battery gauge error. The CA-300 pulls current simultaneously from the backlit display, the thermal detector, and the detector's onboard heating element — this combined draw can spike the instantaneous load enough for the BMS to cut output even when the resting voltage looks fine. A degraded cell with high internal resistance hits that trip threshold faster. Check resting voltage with a multimeter — a cell sitting below 3.5V at rest after a charge has lost enough capacity to cause mid-inspection trips and should be replaced.