About this replacement
Pentax GPS RTK / G3100-R1 — 7.4V Li-ion Replacement Battery (10002)
This 7.4V, 2200mAh Li-ion battery replaces the OEM 10002 pack in the Pentax GPS RTK and G3100-R1 receivers. These units are used for real-time kinematic surveying and geospatial data collection in the field. The cell dimensions match the original housing at 72.34 × 40.10 × 21.30mm, so the pack seats correctly in the receiver bay.
- GPS RTK and G3100-R1 compatibility: Both models run the same 7.4V power rail and use the same OEM part number 10002. The battery connector, BMS handshake protocol, and physical form factor are identical across the two units, so one pack covers either receiver.
- Bench tested on actual hardware: We cycled this pack through power-up, satellite acquisition, and active logging sequences. The BMS held steady during the current draw at satellite lock-on and did not trip during sustained RTK fix sessions.
- Post-install calibration on the Pentax RTK: After fitting a new pack, run a full calibration cycle through the receiver's instrument menu before heading to site. The Pentax RTK maps battery state during calibration — skipping this step causes premature low-battery warnings during your first measurement session, even when the pack is fully charged.
Why the Pentax GPS RTK shuts down at satellite acquisition
When the receiver locks onto satellites, the RF front-end and processing load spike simultaneously. An aged or partially discharged OEM pack can sag below the BMS cutoff threshold at exactly that moment, tripping a shutdown before a fix is established. This looks like a power fault but is actually a voltage floor event. A fresh pack at full charge holds above 7.2V through the acquisition surge without triggering the cutoff.
Pack not recognised after the receiver sat unused through the off-season
Li-ion packs self-discharge during storage. If the Pentax RTK sat unused for several months, the battery may have dropped below the BMS recovery threshold — typically around 2.5V per cell. At that point the BMS enters sleep mode and the receiver either shows no battery indication or refuses to power on. To recover the pack, connect it to a charger that supports low-voltage recovery mode and let it trickle-charge until cell voltage climbs above 3.0V per cell before attempting a normal charge cycle.