{"product_id":"hazet-1979-6-replacement-battery-48v-2500mah-ni-mh","title":"Hazet 1979-6 Compatible Battery 4.8V 2500mAh Ni-MH","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eHazet 1979-6 — 4.8V Ni-MH Replacement Battery (29011)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis 4.8V, 2500mAh Ni-MH pack replaces the OEM 29011 battery in the Hazet 1979-6 diagnostic and testing tool. It fits the 1979-6 directly, matching the original connector, cell count, and BMS communication expected by the instrument. Capacity is rated at 12Wh per cell manufacturer spec.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eHazet 1979-6 fitment:\u003c\/strong\u003e\n    The 1979-6 uses a 4.8V four-cell Ni-MH configuration with a specific contact orientation and charge termination signal. This pack matches that cell arrangement so the instrument's charge management circuit recognises the pack correctly and terminates at the right delta-V threshold.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We ran this pack through the 1979-6's charge cycle and monitored BMS response during probe initialisation. The pack held steady through the initialisation current spike and the charge circuit terminated cleanly without false full-charge flags.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003ePost-installation calibration on the 1979-6:\u003c\/strong\u003e\n    After fitting this pack, run a full calibration cycle through the instrument menu before taking it into the field. The 1979-6 maps battery state during calibration — skipping this step causes premature low-battery warnings during the first measurement session, even with a full 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 1979-6 sat unused in a carry case for months\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eNi-MH cells self-discharge at roughly 1–2% per day at room temperature. After several months in storage, the pack voltage can drop below the instrument's minimum recognition threshold, putting the BMS into a low-voltage lockout state. When this happens, the 1979-6 either shows no battery indicator or refuses to power on even when placed on charge. The fix is to apply a slow trickle charge directly to the pack for 20–30 minutes before attempting a full charge cycle — this brings cell voltage back above the 1.0V-per-cell recovery floor the BMS requires to re-initialise.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eReadings drifting or logging session resetting mid-measurement\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThis happens when sustained sensor load pulls pack voltage below the 1979-6's operating floor during a logging run. Ni-MH voltage under load drops faster than the instrument's indicator suggests, particularly as cells age or after partial discharge cycles. The instrument interprets the voltage dropout as a fault condition and either resets the active session or loses the measurement buffer. If this recurs on a new pack, check that the calibration cycle was completed — an un-calibrated pack causes the instrument to misread state-of-charge and start sessions at an underestimated capacity, triggering a shutdown before the cells are actually depleted.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43360604029018,"sku":"BWCS-HZT197SL-1","price":42.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43360604061786,"sku":"BWCS-HZT197SL-2","price":49.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43360604094554,"sku":"BWCS-HZT197SL-3","price":55.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-HZT197SL-1.webp?v=1778615988","url":"https:\/\/batteryweb.com\/products\/hazet-1979-6-replacement-battery-48v-2500mah-ni-mh","provider":"BatteryWeb","version":"1.0","type":"link"}