About this replacement
Olympus EPOCH LT Ultrasonic Flaw Detector — 6V Ni-MH Replacement Battery (EPLT/BAT)
This is a 6V 2000mAh Ni-MH replacement battery for the Olympus EPOCH LT Ultrasonic Flaw Detector. It slots into the EPOCH LT's battery compartment and restores power to the portable NDT unit. Capacity is 2000mAh (12Wh), matching the original EPLT/BAT specification.
- EPOCH LT platform fit: The EPOCH LT uses a 6V Ni-MH cell with a specific connector and BMS handshake tied to this voltage rail. Swapping to Li-ion or a different voltage pack will trigger an immediate battery fault on the instrument's display — this cell keeps you within the supported chemistry and voltage range the EPOCH LT expects.
- Bench tested on actual hardware: We cycled this cell through the EPOCH LT's charge circuit and monitored BMS communication at each stage. The protection circuit handled charge termination correctly and passed the instrument's internal battery verification without fault codes.
- First-use self-test protocol: After installing this battery, let the EPOCH LT complete its full power-on self-test without interruption. The instrument runs a BMS verification sequence at startup — cutting power during this window can latch a false battery fault that won't clear until the next full reboot cycle.
Why the EPOCH LT shows a battery fault on the first few charge cycles
The EPOCH LT's charge IC applies conservative termination thresholds calibrated to a cell it has already characterised over several cycles. A fresh Ni-MH cell has slightly different internal resistance compared to a broken-in one, so the instrument's BMS may flag a low-capacity warning or fault on cycles one through three. This is a BMS learn-cycle behaviour, not a faulty cell. Run two to three complete charge-discharge cycles on the EPOCH LT before treating any battery warning as a genuine fault. By cycle three, the charge IC will have profiled the cell and termination behaviour normalises.
EPOCH LT not powering on after battery sat in storage
Ni-MH cells self-discharge to roughly 1.0V per cell in long-term storage — on a 5-cell 6V pack, that can drop total pack voltage below the EPOCH LT's BMS recovery threshold, causing the instrument to appear completely dead. The BMS blocks power output to protect downstream circuitry when it reads below this floor. Place the pack on a compatible Ni-MH charger for a trickle pre-charge session before attempting to boot the EPOCH LT. Once pack voltage climbs back above approximately 5.5V, the BMS releases and the instrument will power on normally.