Sanyo CR17335SE-R PLC Replacement Battery 3V 1800mAh

Sanyo CR17335SE-R — 3V Li-MnO2 Replacement Battery (CR17335SE-R)

This is a 3V lithium manganese dioxide cell rated at 1800mAh (5.4Wh), built to the CR17335SE-R specification. It fits PLC backup applications cross-referenced under GT15-BAT and ER2/3A. Its role is to hold SRAM program memory and keep the real-time clock running when main power is cut.

• GT15-BAT and ER2/3A cross-reference: These part numbers share the same 2/3A cell format — 35mm length, 17mm diameter — and the same 3V nominal rail. Any controller specifying one of these part numbers will accept this cell without modification to the battery holder or connector.
• Bench tested on actual hardware: We ran this cell on a PLC backup circuit and confirmed the BMS float charge accepted the cell immediately at installation. Open-circuit voltage on arrival measured 3.0V to 3.1V, consistent with factory storage charge.
• Hot-swap protocol for SRAM retention: Always replace this cell with the PLC powered on and in RUN mode. Removing the old cell while the controller is de-energised will cause SRAM to lose all stored program data. If the PLC was off during swap, reload the program from your programming device before restarting.

PLC battery alarm not clearing after confirmed good installation

Some controllers latch the battery alarm in firmware and will not clear it automatically when a new cell is detected. The alarm flag must be reset manually inside the programming software — typically under diagnostics or system settings. On Mitsubishi Q-series and FX-series controllers, this is done via GX Works by navigating to the special relay or special register assigned to the battery status flag and resetting it. Refer to the controller's system device list for the exact register address.

New cell reading below 3V on the controller's battery monitor

Li-MnO2 cells ship at a reduced storage voltage — typically 2.8V to 2.95V — to slow self-discharge during transit. Once installed in a powered PLC, the float charge circuit brings the reading up to the nominal 3V range within a few hours. If the controller still reports low battery after 24 hours on power, measure the cell directly with a multimeter across the terminals. A healthy cell at rest will read at or above 3.0V; anything below 2.8V after that period warrants a cell swap.