{"product_id":"acutrac-22-pro-replacement-battery-84v-700mah-ni-mh","title":"Acutrac NB-1X7 Survey Battery 8.4V 700mAh Ni-MH","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eAcutrac 22 Pro \/ Digisat Pro Series — 8.4V Ni-MH Replacement Battery (NB-1X7)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is an 8.4V 700mAh Ni-MH replacement battery for the Acutrac 22 Pro surveying instrument. It also fits the Digisat Pro, Digiair, and MKII satellite signal meter. Voltage and connector match the original NB-1X7 specification exactly.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003e22 Pro and Digisat Pro platform fit:\u003c\/strong\u003e\n    These models share the same 8.4V power rail and NB-1X7 footprint. The connector orientation, cell count, and BMS handshake requirements are identical across the family, so one battery covers all listed variants 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 charge and discharge cycles on the 22 Pro. The BMS accepted the charge profile without fault flags, and the instrument's power management circuit read cell state correctly throughout each cycle.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eField calibration before first deployment:\u003c\/strong\u003e\n    After installing this battery, run a full calibration cycle through the instrument menu before heading into the field. The 22 Pro maps battery state during calibration — skipping this step causes premature low-battery warnings on the first measurement session, even with a fully charged pack.\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 the Acutrac sat unused in a carry case for months\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eNi-MH cells self-discharge at roughly 1–2% per day at room temperature. A pack left unused for several months can drop below the BMS recovery threshold — typically around 6.0V for an 8.4V Ni-MH pack — causing the protection circuit to latch open. When this happens, the instrument shows no sign of life even after placing it on charge. The fix is a slow trickle charge at low current (around 50mA) directly across the cell terminals using a bench charger until the pack reaches 7.0V, at which point the BMS will re-initialise and accept a normal charge cycle.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eReadings drifting or resetting mid-session during continuous logging\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eDuring sustained sensor load — continuous GPS or signal logging with backlight active — current draw climbs steadily and can cause brief voltage dropouts across the pack. The 22 Pro's processor interprets these dropouts as a low-voltage event and either resets or interrupts the active logging session. This is not a faulty battery; it is a cell-voltage sag issue common to Ni-MH chemistry under sustained draw. To reduce dropout risk, dim the backlight and close unused instrument functions during long logging sessions, keeping continuous draw below the threshold where cell voltage sags past 7.2V under load.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43360574767194,"sku":"BWCS-ACT220SL-1","price":26.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43360574799962,"sku":"BWCS-ACT220SL-2","price":29.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43360574832730,"sku":"BWCS-ACT220SL-3","price":32.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-ACT220SL-1.webp?v=1778615988","url":"https:\/\/batteryweb.com\/products\/acutrac-22-pro-replacement-battery-84v-700mah-ni-mh","provider":"BatteryWeb","version":"1.0","type":"link"}