Omron CJ2M - DATE function

[Jothiswarup]

Hello all,

I am trying to set PLC clock using DATE function.
When DATE function is enabled, I can see A351 to A354 change to the register value (D100 to D103).
But when the rung is false, A351 to A354 reverts to PLC clock time.

What am I doing wrong?

 

[IO_Rack]

All the Date settings are in BCD. You are writing them in Decimal. The instruction is probably failing due to "out of range", therefore reverting to the old time/date. You can check for that using P_ER immediately after the DATE function.

You'll need to monitor in HEX to view them in BCD. They'll be preceded with "#" instead of "&".

 

[Jothiswarup]

All the Date settings are in BCD. You are writing them in Decimal. The instruction is probably failing due to "out of range", therefore reverting to the old time/date. You can check for that using P_ER immediately after the DATE function.

You'll need to monitor in HEX to view them in BCD. They'll be preceded with "#" instead of "&".

Is this what you are referring to? If so, it is still the same.
Also to clarify, I am simulating this. Not sure if that makes a difference.

 

[IO_Rack]

Yes that's what I was referring to. Sorry, it actually shows "Hex" in the monitoring window. If you input values either by the watch window or in ladder, you'll need to precede the value with "#". But you already learned that.

I'm going to say the Date function cannot be simulated for a couple of reasons. It is a function that is stored and retained on the PLC. Simulation is working with an imaginary PLC so it's using your computer's time to view the clock. Notice when you double click the PLC Clock, they are identical. << I probably didn't explain that well but I think you get it. I know there are other limitations to simulation like PID and high speed outputs for similar reasons.

I also tested this on a real PLC here on my bench. What you show in your pics works fine in Hex (BCD). I then tested in the simulator and got the same results you did.