About this replacement
Olympus 38DL Plus Ultrasonic Thickness Gauge — 10.8V Li-ion Replacement Battery (38-BAT)
This is a 10.8V, 2600mAh Li-ion replacement battery for the Olympus 38DL Plus Ultrasonic Thickness Gauge. It fits the 38DL Plus series using OEM part numbers 38-BAT, CW-38-BAT, and Epoch4. The pack slots into the same battery bay and connects via the original interface without modification.
- 38DL Plus and Epoch4 platform compatibility: These instruments share the same 10.8V battery rail, connector pinout, and BMS handshake protocol. A single pack covers both device families without any adapter or wiring change.
- Bench tested on actual hardware: We ran this pack through the 38DL Plus power-on sequence, probe initialisation, and sustained measurement logging. The BMS held stable across the current spike at transducer power-up and did not trip during continuous scan sessions.
- Calibration cycle after installation: After fitting a new pack, run a full calibration cycle through the instrument menu before field deployment. The 38DL Plus maps battery state during calibration — skipping this step causes premature low-battery warnings to appear during your first measurement session, even with a full charge.
BMS cutoff when the transducer initialises on power-up
The 38DL Plus sends a short high-current pulse to the probe module during initialisation. On a degraded or deeply discharged pack, this spike can trip the BMS overcurrent threshold before the instrument reaches its home screen. The pack is not faulty — the BMS has latched into protection mode. Charge the battery to at least 11.5V before reinserting, then power on without a probe attached first to let the instrument boot fully before connecting the transducer.
Readings resetting or drifting mid-session during continuous logging
During extended logging runs, sustained sensor load can cause a brief voltage dropout if the cell is below 50% capacity. The 38DL Plus interprets this dropout as a power event and resets the active measurement session. This is not a firmware fault — it is a voltage sag issue at the cell level. Keep the pack above 11.1V during long field sessions, or carry a second charged battery and swap at the halfway point rather than running the pack to depletion.