CJ2 CPU Unit Software User's Manual - CIP ETI

CautionExecute online edit only after confirming that no adverse effects will becaused by extending the cycle time. Otherwise, the input signals may not bereadable.Confirm safety at the destination node before transferring a program, PLCSetup, I/O tables, I/O memory contents, or parameters to another node orchanging contents of the any of these items. Transferring or changing datacan result in unexpected system operation.The CJ2 CPU Units automatically back up the user program and parameterdata to flash memory when these are written to the CPU Unit. I/O memoryincluding the DM, EM, and Holding Areas), however, is not written to flashmemory.The DM, EM, and Holding Areas can be held during power interruptions witha battery. If there is a battery error, the contents of these areas may not beaccurate after a power interruption. If the contents of the DM, EM, and HoldingAreas are used to control external outputs, prevent inappropriate outputsfrom being made whenever the Battery Error Flag (A402.04) is ON.Tighten the terminal screws on the AC Power Supply Unit to the torque specifiedin the operation manual. The loose screws may result in burning or malfunction.Do not touch the Power Supply Unit when power is being supplied or immediatelyafter the power supply is turned OFF. The Power Supply Unit will be hotand you may be burned.When connecting a personal computer or other peripheral device to a PLC towhich a non-insulated Power Supply Unit (CJ1W-PD022) is mounted, eitherground the 0 V side of the external power supply or do not ground the externalpower supply at all ground. A short-circuit will occur in the external powersupply if incorrect grounding methods are used. Never ground the 24 V side,as shown below.Wiring in Which the 24-V Power Supply Will Short24 VNon-insulatedDC power supply0 VPeripheralcable0 VFGPower SupplyUnitCPU UnitPeripheral device (e.g.,personal computer)24 CJ2 CPU Unit Software User’s Manual