{"product_id":"topcon-field-controller-fc100-replacement-battery-74v-3400mah-li-ion","title":"Topcon BT-30 Field Controller FC100 Replacement Battery 7.4V 3400mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eTopcon FC100 \/ FC2000 Field Controller — 7.4V Li-ion Replacement Battery (BT-30)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis 7.4V, 3400mAh Li-ion battery replaces the OEM BT-30, BT-62Q, BT-65Q, and BT-66Q packs used in Topcon FC100 and FC2000 Field Controllers. These handheld data collectors run GPS positioning, mapping, and real-time site measurement software in the field. Same voltage rail, same connector, same BMS handshake as the original pack.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eFC100 and FC2000 compatibility:\u003c\/strong\u003e\n    Both controllers share the same battery bay geometry, 7.4V nominal rail, and OEM BMS communication protocol. The BT-30 form factor covers all hardware revisions of both models without modification.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We ran this pack through a full charge and discharge cycle on an FC100 unit. The BMS correctly reported state of charge throughout, and the controller accepted the pack without a battery-fault flag at startup.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003ePre-deployment calibration cycle:\u003c\/strong\u003e\n    After fitting this battery, run a full calibration cycle through the FC100's instrument menu before heading to site. The controller maps battery state during calibration — skipping this step causes premature low-battery warnings during your first measurement session in the field.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eFC100 shutting down mid-session after months in the carry case\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eLi-ion cells self-discharge during storage. If an FC100 sits unused for several months, the pack voltage can drop below the BMS recovery threshold — typically around 2.5V per cell, or roughly 5.0V across the pack. At that point the BMS latches into a protective sleep state and the controller will not power on. Placing the battery on a charger that supports a trickle or recovery pre-charge mode will bring it back. Once cell voltage climbs above 3.0V per cell, the BMS exits sleep and a normal charge cycle completes.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eGPS lock acquired, then FC100 resets or freezes during active data logging\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eSustained sensor and radio load during active GPS logging draws significantly more current than the idle state. If the battery cells have aged or the pack has a weakened cell, voltage sags under this load and dips below the controller's cutoff threshold — triggering a mid-session reset. This is different from a BMS fault; the unit restarts rather than shutting off cleanly. Fit a fresh pack, run the calibration cycle, and check that the controller holds voltage above 7.0V during a live GPS lock session before returning to site.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43360737919066,"sku":"BWCS-TOP100HL-1","price":38.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43360737951834,"sku":"BWCS-TOP100HL-2","price":44.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43360737984602,"sku":"BWCS-TOP100HL-3","price":48.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-TOP100HL-1.webp?v=1778616277","url":"https:\/\/batteryweb.com\/products\/topcon-field-controller-fc100-replacement-battery-74v-3400mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}