About this replacement
Yaskawa YRC1000 — 3.6V Li-MnO2 Replacement Battery (ER6BD-WK77P)
This 3.6V Li-MnO2 cell replaces the ER6BD-WK77P backup battery in the Yaskawa YRC1000 industrial robot controller. It maintains real-time clock and SRAM data when main power is removed. Rated at 2000mAh (7.2Wh), it matches the original cell dimensions at 53.30 × 16.10 × 14.90mm.
- YRC1000 controller fit: The YRC1000 uses this cell specifically to hold RTC and volatile memory state during power-down events. The connector and cell format are matched to the controller's battery housing — no adapter or modification needed.
- Bench tested on actual hardware: We confirmed open-circuit voltage on delivery, verified connector polarity, and checked that the cell holds stable voltage under the YRC1000's float charge circuit without triggering a battery alarm on reconnection.
- Hot-swap procedure for the YRC1000: Always replace this cell with the controller powered on and in RUN mode. Removing the battery while the YRC1000 is powered off will cause SRAM loss — job programs, I/O configuration, and RTC data will be erased and must be reloaded from a programming device.
Why the YRC1000 battery alarm stays on after a confirmed good installation
The YRC1000 does not automatically clear a battery alarm when a new cell is installed. The alarm is latched in the controller's fault log and requires a manual reset through the YRC1000 programming pendant or connected PC software. A fresh Li-MnO2 cell may also read slightly below 3.6V on first connection — this is normal for cells shipped in storage mode and does not indicate a fault. Once the controller's float charge circuit runs for several hours, voltage rises to rated level and the alarm can then be cleared cleanly.
YRC1000 clock showing wrong date and time after battery swap
If the old cell was removed while the controller was powered off, the RTC lost its reference entirely — installing a new cell restores the circuit but does not restore the time value. The controller will typically default to a reset timestamp, which can corrupt event logs and affect any time-triggered robot tasks. Set the correct date and time manually through the YRC1000 pendant under System → Clock settings immediately after the battery alarm is cleared. Confirm the RTC is holding time correctly by cycling controller power and rechecking the timestamp.