{"product_id":"fey-replacement-battery-36v-1700mah-li-socl2","title":"Fey PA-A3293 PLC Backup Compatible Battery 3.6V 1700mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eFey PA-A3293 — 3.6V Li-SOCl2 Replacement Battery\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.6V, 1700mAh lithium thionyl chloride cell that replaces the Fey PA-A3293 and PA-A3293.R001 backup battery in Mitsubishi PLC systems. It maintains SRAM program memory and the real-time clock when main power is removed. Without a functioning backup cell, a power interruption wipes the controller's stored program.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eMitsubishi PLC backup compatibility:\u003c\/strong\u003e\n    Mitsubishi controllers in this range use a dedicated backup rail to float-charge the memory cell. The PA-A3293 footprint and connector spec match that rail directly — no adapter, no modification.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We confirmed the cell holds 3.6V nominal under the micro-amp standby draw of the SRAM and RTC circuit. The BMS does not trip under this load profile, and float charging begins immediately on controller power-up.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eHot-swap rule for this controller:\u003c\/strong\u003e\n    Always replace this battery with the PLC powered on and in RUN mode. Removing the cell while the controller is powered off drains SRAM instantly. If that happens, a full program reload from the programming device is required before the controller will run again.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the Mitsubishi PLC loses program memory after a battery swap\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eSRAM in these controllers has no capacitor buffer. The backup cell is the only power source keeping memory alive when mains power is off. Pull the cell with the PLC de-energised, even briefly, and the SRAM contents are gone. Reconnecting a fresh cell restores backup power but does not restore lost data. The only recovery is reloading the program from a connected programming device or stored backup file.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eBattery alarm not clearing after a confirmed good installation\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eMitsubishi PLCs latch the battery alarm flag in the special relay register — it does not reset automatically when the new cell is fitted. The controller sees a valid voltage but the fault flag stays set until cleared in software. Open the programming software, navigate to the special relay or diagnostic register for battery status, and force a reset of that flag. After clearing, cycle controller power to confirm the alarm does not reappear.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43415988306010,"sku":"BWCS-MMR967SL-1","price":22.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43415988338778,"sku":"BWCS-MMR967SL-2","price":25.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43415988371546,"sku":"BWCS-MMR967SL-3","price":27.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-MMR967SL-1.webp?v=1779758841","url":"https:\/\/batteryweb.com\/products\/fey-replacement-battery-36v-1700mah-li-socl2","provider":"BatteryWeb","version":"1.0","type":"link"}