{"product_id":"fukuda-multiline-laser-replacement-battery-37v-3600mah-li-ion","title":"Fukuda FLE-444R Multiline Laser Replacement Battery 3.7V 3600mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eFukuda Multiline Laser Series — 3.7V Li-ion Replacement Battery (FLE-444R)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.7V, 3600mAh Li-ion replacement battery for Fukuda multiline laser devices. It fits the FLE-444R, EK-189, EK-289, and related models used in construction leveling and surveying. Voltage and cell chemistry match the original pack specification.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eFLE-444R, EK-189, EK-289 platform fit:\u003c\/strong\u003e\n    These models share the same 3.7V single-cell architecture, connector pinout, and BMS handshake protocol. One replacement pack covers the full group 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 power-on initialisation and line-projection cycles. The BMS held stable across repeated sensor activation events and showed no nuisance cutoffs during sustained laser output.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFirst-use calibration on Fukuda multiline lasers:\u003c\/strong\u003e\n    After installing this pack, run a full calibration cycle through the instrument menu before taking it to site. The laser maps battery state during calibration. Skip this step and the unit will flag premature low-battery warnings during your first alignment session, even with a full charge.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eBMS lockout after a Fukuda laser sat unused in a carry case for months\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eLi-ion cells self-discharge during storage. If a Fukuda multiline laser sits unused long enough, the cell voltage can drop below the BMS's minimum recovery threshold — typically around 2.5V. At that point the BMS enters a protective sleep state and the instrument will not power on or accept a charge. To recover the pack, apply a trickle charge via a compatible Li-ion charger set to recovery mode and hold it there until the cell climbs above 2.8V. Once past that threshold the BMS re-initialises and normal charging resumes.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eReadings drifting or resetting mid-session on the FLE-444R\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eUnder sustained laser output, the draw on the cell is steady but non-trivial. If the cell has degraded or is partially discharged, voltage can sag enough mid-session for the instrument's processor to register an undervoltage event and reset — dropping your reference lines without warning. This is not a firmware fault. Check resting cell voltage before deployment: a healthy pack at full charge should read between 4.15V and 4.20V at the terminals. Anything below 4.0V at rest after a full charge indicates cell capacity loss and the pack should be replaced.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43360731005018,"sku":"BWCS-FKD440SL-1","price":41.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43360731037786,"sku":"BWCS-FKD440SL-2","price":48.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43360731070554,"sku":"BWCS-FKD440SL-3","price":53.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-FKD440SL-1.webp?v=1778616209","url":"https:\/\/batteryweb.com\/products\/fukuda-multiline-laser-replacement-battery-37v-3600mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}