{"product_id":"doppler-fd390-replacement-battery-96v-700mah-ni-mh","title":"Doppler FD390 Ultrasound Compatible Battery 9.6V 700mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eDoppler FD390 — 9.6V Ni-MH Replacement Battery (6HR-4UC)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 9.6V, 700mAh Ni-MH replacement battery for the Doppler FD390 and FD-390 handheld ultrasound device. It replaces OEM part number 6HR-4UC. The cell pack matches the original voltage rail and connector required by this portable ultrasound system.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eFD390 and FD-390 compatibility:\u003c\/strong\u003e\n    Both model designations use the same 6HR-4UC cell pack, identical connector pinout, and the same BMS handshake protocol. One battery fits both.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We cycled this pack through charge and discharge on the FD390 platform. The BMS completed its verification handshake without fault flags on the first full cycle.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003ePost-installation power-on cycle:\u003c\/strong\u003e\n    After fitting this battery, allow the device to complete its full power-on self-test without interruption. The FD390 runs a BMS verification sequence at startup. Cutting power during that sequence can trigger 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\"\u003eLow battery alarm firing on a fully charged replacement pack\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThe FD390's BMS stores charge profile data calibrated to the original OEM cell. A new Ni-MH cell has a slightly different internal resistance curve, so the BMS may read it as below threshold on the first few cycles. This is not a fault with the replacement pack. Run one complete charge-discharge cycle and the BMS recalibrates its state-of-charge estimate to the new cell's profile. After that cycle, the alarm threshold behaves normally.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eDevice will not power on after battery has been stored unused\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 that has sat in storage for several weeks can drop below the BMS recovery threshold — typically around 8.5V for a 9.6V Ni-MH pack — and the device will not respond to the power button. Place the pack on the charger for a full uninterrupted charge cycle before attempting to power on. If the charger does not begin the charge cycle within five minutes of connection, disconnect, wait 30 seconds, and reconnect to trigger the recovery charge mode.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43381509193818,"sku":"BWCS-LFD390MD-1","price":31.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43381509226586,"sku":"BWCS-LFD390MD-2","price":36.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43381509259354,"sku":"BWCS-LFD390MD-3","price":39.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-LFD390MD-1.webp?v=1778901340","url":"https:\/\/batteryweb.com\/products\/doppler-fd390-replacement-battery-96v-700mah-ni-mh","provider":"BatteryWeb","version":"1.0","type":"link"}