Topcon FC-5000 Replacement Battery 3.7V 13600mAh Li-ion

Topcon FC-5000 — 3.7V Li-ion Replacement Battery (1013591-01)

This 3.7V Li-ion battery replaces part number 1013591-01 in the Topcon FC-5000 field controller. Capacity is 13600mAh (50.32Wh). The FC-5000 is a rugged handheld used on survey and construction sites for data collection and positioning work.

• FC-5000 and FC5000 fit confirmation: Both model designations refer to the same Topcon field controller hardware. The connector pinout, BMS handshake protocol, and 3.7V voltage rail are identical across the production run. This replacement uses the same cell configuration the unit expects.
• Bench tested on actual hardware: We cycled this pack through the FC-5000 charge circuit and monitored the BMS during power-on initialisation, GPS lock, and sustained data logging. The BMS held stable across all three load states with no unexpected cutoff events.
• Post-install calibration on the FC-5000: After fitting this battery, run a full calibration cycle through the FC-5000 instrument menu before your first field deployment. The controller maps battery state during that calibration pass. Skip it and the unit will flag premature low-battery warnings during your first measurement session — even with a full charge.

FC-5000 BMS cutoff when GPS or sensor module initialises

When the FC-5000 powers up its positioning module, there is a brief current spike as the GPS receiver initialises and acquires signal. A degraded or deeply discharged original pack often cannot sustain voltage through that spike, causing the BMS to trip and the unit to shut down immediately after the splash screen. This replacement pack's cell capacity and internal resistance are matched to handle that initialisation draw without triggering cutoff. If the issue persists after fitting, check that the battery contacts on the unit are clean and making full contact.

Readings drifting or session data resetting mid-logging

During a sustained logging session, the FC-5000 draws continuous current across GPS, display, and storage simultaneously. If the pack's voltage sags under that combined load, the controller can experience a momentary dropout — enough to reset the active session or corrupt a measurement string. This is distinct from a full shutdown: the unit may recover and continue, but the logged data from that window is lost. Fitting a pack at full rated capacity and ensuring the calibration cycle has been completed both reduce the likelihood of voltage sag under sustained sensor load.