About this replacement
Afriso DIT 01 / DIT 02 / Unimes E — 3.6V Li-SOCl2 Replacement Battery (68309)
This is a 3.6V 2700mAh lithium thionyl chloride cell for the Afriso DIT 01, DIT 02, DIT 10, and Unimes E digital thermometers. It replaces OEM part numbers 68309 and 50108901. The cell measures 50.00 × 16.00 × 14.60mm and fits the original battery compartment without modification.
- DIT 01, DIT 02, DIT 10, and Unimes E compatibility: All four instruments run from the same 3.6V supply rail and use the same physical cell format. The BMS threshold and connector are identical across the range, so one cell specification covers all models listed.
- Bench tested on actual hardware: We ran this cell under the probe initialisation cycle on a DIT 01. The BMS held through the start-up current spike without tripping, and the instrument completed the self-test sequence cleanly on first power-up.
- Post-install calibration cycle: After fitting this cell, run a full calibration cycle through the instrument menu before deploying to the field. The DIT series maps battery state during calibration. Skipping this step causes premature low-battery warnings to appear during the first measurement session, even with a fresh cell at full capacity.
BMS lockout after the DIT instrument sat unused in a carry case for months
Li-SOCl2 cells have extremely low self-discharge, but the Afriso DIT instruments draw a small standby current even when switched off. Over several months in storage, that draw can pull the cell below the BMS recovery threshold. When this happens, the instrument shows no response on power-up — not a flat battery reading, just nothing. The BMS has entered sleep mode. Apply a brief charge pulse from a compatible 3.6V source across the cell terminals for 10–15 seconds to bring the cell above the 3.0V recovery floor, then refit and power on.
Readings drift or reset mid-session during a long logging run
Sustained sensor load during continuous logging draws more current than single-shot measurements. If the original cell has aged and its internal resistance has risen, the voltage sags under that sustained load even when the resting voltage still reads normal. The instrument interprets this sag as a low-voltage event and either resets the session or drops the probe power momentarily, causing a gap or drift in the logged data. Swap in a fresh cell and confirm resting voltage is at or above 3.6V before starting the logging session.