{"product_id":"quest-ac-tester-replacement-battery-108v-2700mah-ni-mh","title":"Quest AC-tester 704080 Replacement Battery 10.8V 2700mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eQuest AC-tester — 10.8V Ni-MH Replacement Battery (704080)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis 10.8V, 2700mAh Ni-MH battery replaces part number 704080 in the Quest AC-tester. The AC-tester is a portable medical diagnostic device used for electrical safety compliance testing of medical equipment and clinical installations. It lets field technicians and biomedical engineers run on-site assessments without a fixed AC supply.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eAC-tester platform fit:\u003c\/strong\u003e\n    The 704080 cell pack uses a specific connector pinout and BMS handshake tied to the AC-tester's charge IC. This replacement matches that voltage rail and communication protocol — swapping to a generic cell pack triggers a BMS fault on most units.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We cycled this battery through the AC-tester's full charge and load sequence. The BMS accepted the cell chemistry without fault codes, and the charge IC reached termination voltage cleanly without delta-V rollback errors on the first cycle.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003ePost-installation self-test cycle:\u003c\/strong\u003e\n    After fitting the battery, let the AC-tester complete its full power-on self-test without interruption. Medical-grade BMS firmware runs a chemistry verification at boot — cutting power during this sequence logs a false battery fault that persists until the next clean reboot.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the AC-tester flags a battery fault after a confirmed full charge\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe AC-tester's BMS holds OEM calibration thresholds from the factory cell pack. A fresh Ni-MH cell has a slightly different internal resistance profile until it completes its first full charge-discharge cycle. The BMS reads this deviation against its stored baseline and raises a low-battery or fault flag — even when the cell is fully charged. Run one complete charge-discharge cycle before clinical use. After that single cycle, the BMS recalibrates and the fault clears.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eAC-tester will not power on after the replacement battery sat in storage\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eNi-MH cells self-discharge at roughly 1–2% per day. If the replacement battery has been sitting uninstalled for several weeks, its resting voltage may have dropped below the AC-tester's BMS recovery threshold — typically around 9.0V for a 10.8V Ni-MH pack. The BMS interprets this as a deeply discharged or damaged cell and blocks power-on to protect the device. Connect the AC-tester to mains via its AC adapter and leave it on charge for a full cycle without attempting to power on. Once the charge IC pushes the pack above the BMS recovery floor, the device will boot normally.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43381371142234,"sku":"BWCS-QCT408MD-1","price":76.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43381371175002,"sku":"BWCS-QCT408MD-2","price":90.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43381371207770,"sku":"BWCS-QCT408MD-3","price":101.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-QCT408MD-1.webp?v=1778900449","url":"https:\/\/batteryweb.com\/products\/quest-ac-tester-replacement-battery-108v-2700mah-ni-mh","provider":"BatteryWeb","version":"1.0","type":"link"}