About this replacement
Southern S86 GPS — 7.4V Li-ion Replacement Battery (BA0200006)
This is a 7.4V, 10400mAh (76.96Wh) Li-ion replacement for the Southern S86 GPS receiver. It matches the OEM part number BA0200006 and fits directly into the S86 GPS battery bay. The S86 is a professional land surveying receiver, so this battery needs to hold voltage steadily across full field sessions.
- S86 GPS receiver fit: The S86 platform uses a single high-capacity Li-ion pack to power both the GNSS engine and the internal data logger simultaneously. The BA0200006 form factor and connector match the OEM housing — the BMS handshake with the receiver completes without fault codes.
- Bench tested on actual hardware: We cycled this pack under a combined GNSS-tracking and data-logging load profile. The BMS held the output rail stable through satellite acquisition bursts and did not trip on the inrush current when the receiver's radio module initialised.
- First field deployment prep: After fitting the new pack, run a full instrument calibration cycle through the S86 menu before your first survey session. The receiver maps battery state during calibration — skipping this step causes the low-battery indicator to fire prematurely on the first job, even with a full charge.
BMS cutoff when the S86 radio module powers up at startup
When the S86 initialises, the internal UHF or Bluetooth radio module draws a short inrush current on top of the GNSS engine startup load. On a depleted or deeply discharged pack, this combined spike can push the cell voltage below the BMS protection threshold, triggering an immediate cutoff. The receiver then appears to power on and immediately shut off, which is often misread as a faulty battery. Charge the pack to above 7.0V before attempting startup — at lower states of charge, the inrush headroom is not there.
S86 showing erratic battery percentage after replacing the pack
The S86 tracks battery state against a learned voltage curve from the previous pack. When a new cell is fitted, the receiver's charge indicator recalibrates over the first one or two full discharge-charge cycles, so the percentage display will jump or read low even on a full battery. This is not a fault in the replacement pack. Run two complete field cycles — full charge, full session discharge, full recharge — and the percentage display stabilises. After cycle two, the indicator should track within a few percent of actual capacity.