{"product_id":"ge-mac-12-replacement-battery-36v-1100mah-ni-mh","title":"GE MAC 12 ECG Replacement Battery 3.6V 1100mAh Ni-MH","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eGE MAC 12 \/ MAC 15 — 3.6V Ni-MH Replacement Battery (401086-002D)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.6V, 1100mAh Ni-MH replacement battery for the GE MAC 12 and MAC 15 electrocardiograph machines. It restores portable operation when the original cell degrades and the unit can no longer run without AC power. Both the MAC 12 and MAC 15 share the same battery compartment, connector, and BMS handshake, so one SKU covers both platforms.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eMAC 12 and MAC 15 shared platform:\u003c\/strong\u003e\n    GE built both ECG units on the same power rail and battery management architecture. The connector pinout, cell voltage requirements, and BMS communication protocol are identical across both models, which is why OEM part 401086-002D covers the full range.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We cycled this cell through charge and discharge on the MAC platform and confirmed the BMS accepted the new cell without flagging a chemistry mismatch or triggering a persistent fault code.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003ePost-swap self-test protocol:\u003c\/strong\u003e\n    After fitting this battery, let the MAC complete its full power-on self-test without interruption. The device runs a BMS verification sequence at startup — cutting power during this window causes a false battery fault that latches 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 MAC 12 alarms low battery immediately after a confirmed full charge\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThe MAC's BMS holds a learned capacity threshold calibrated to the previous cell's charge history. A fresh Ni-MH cell starts with no cycle data, so the BMS compares the new cell's internal resistance profile against its stored baseline and flags a mismatch. This usually presents as a low-battery alarm within the first minute of use, even though the cell is at full voltage. Running one complete charge-discharge cycle gives the BMS enough data to update its learned threshold and clear the alarm.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eMAC 12 will not power on after the battery has been sitting unused\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eNi-MH cells self-discharge at roughly 1–2% per day. A battery stored in a drawer for several months can drop below the MAC's BMS recovery threshold — typically around 3.0V — at which point the BMS locks out the cell to prevent damage. The device will show no response at all: no boot screen, no alarm. Connect to AC power first, confirm the charger indicator activates, and leave the unit on charge for a full cycle before attempting battery-only operation.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43381491269722,"sku":"BWCS-GMC120MD-1","price":29.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43381491302490,"sku":"BWCS-GMC120MD-2","price":33.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43381491335258,"sku":"BWCS-GMC120MD-3","price":36.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-GMC120MD-1.webp?v=1778901266","url":"https:\/\/batteryweb.com\/products\/ge-mac-12-replacement-battery-36v-1100mah-ni-mh","provider":"BatteryWeb","version":"1.0","type":"link"}