About this replacement
Deviser S30 — 7.4V Li-Polymer Replacement Battery (BAT-S30)
This 7.4V 1800mAh Li-Polymer battery replaces the BAT-S30 pack in the Deviser S30 surveying instrument. It fits the S30 used in construction and land surveying applications where field uptime matters. Voltage, connector, and BMS communication match the original pack exactly.
- S30 platform fit: The S30 uses a dedicated Li-Polymer form factor at 64.00 × 50.60 × 8.80mm with a BMS handshake tied to the instrument's power rail. Swapping to this pack preserves that handshake so the instrument reads charge state correctly from first boot.
- Bench tested on actual hardware: We cycled this pack through the S30's full power sequence, including sensor initialisation and sustained logging load. The BMS held voltage within spec across the draw curve and did not trip during probe power-up spikes.
- Pre-deployment calibration cycle: After installing this pack, run a full calibration cycle through the S30's instrument menu before taking it into the field. The instrument maps battery state during calibration — skipping this step causes premature low-battery warnings during your first measurement session.
BMS lockout after the S30 sat unused in a carry case for months
Li-Polymer cells self-discharge slowly in storage. If the S30 sits unused long enough, cell voltage drops below the BMS recovery threshold — typically around 2.5V per cell — and the pack enters a protective lockout state. Placing the pack on charge at this point may show no response on the charger, because the BMS is blocking the charge path until it receives a wake signal. Connect the instrument to its original charger and hold the power button for 10 seconds to trigger the BMS re-initialisation sequence, then allow a full uninterrupted charge cycle before powering on the instrument.
S30 display shows inconsistent battery percentage after every reboot
The S30 reads battery state by mapping cell voltage to a threshold table stored in firmware. A new pack has a slightly different discharge curve than a worn original, so the instrument's percentage indicator can jump or reset until the firmware re-maps to the new cell's curve. This is not a fault with the pack — it resolves after two to three full charge and discharge cycles. Run the instrument through those cycles with the calibration menu active and the percentage readout will stabilise at 3.7V per cell resting voltage.