Omron CQM1H PLC Holding Relay

[kabir]

Hello folks,

Recently I've encountered as failed obsolete HMI connected to an Omron CQM1H PLC, so decided to give advanced hmi a shot at replacing It. Since both PLC and original HMI programs are available no programming changes were required in the PLC. The advanced HMi displays were created with controls and mapped to required PLC addresses.

The application works and communicates perfectly except that I have not been able to write to the holding relays HRXX.XX. Folks can you offer some assistance here.

I should say that even though I have been doing PLC development for many years Omron is not the brand that I usually interact with.

Seeking some expert advice here.

[Archie]

Try it with just "Hxx.xx" and not "HR"

[kabir]

I tried HRXX.XX and HXX.XX, with HRXX.XX I get an error string format incorrect, with HXX.XX I don't get any error but the write is not working. I have tried reading the status of HXX.XX to a text display and it works well the problem looks to be in writing to the PLC. I have even tried using code like Me.OMRONHOSTLINKDRIVERNAME.Write("HXX.XX",1) but still no effect.

[kabir]

I doubt that nobody has attempted this before.. Omron folks where are you?

[Archie]

Can you run a serial port sniffer to see what reply is coming from the PLC when you try to write?

[kabir]

I can try with a serial port sniffer to see what were getting back from the PLC next time I visit this site. I write to multiple 'D' resisters without error as well as I can read HRXX.XX but not write to it so I am thinking it maybe driver related. I would have loved to hear that this was successfully done by someone already to know that it is not actually an advanced HMI driver issue.

[Archie]

I just tried this out with version 3.99x and a CP1H processor.

I added a BasicLabel to the form and set PLCAddressValue and PLCAddressKeypad both to H0.0

I then ran the application, clicked the BasicLabel, typed a 1 on the keypad and it changed the value in the PLC.

I then added a second BasicLabel pointing to H0.1 and did the same test. It worked as expected also.

[kabir]

Ah yes Archie got it working so there is hope yet, back to the drawing board.

What driver are you using?

[Archie]

Used the OmronSerialFINSCom driver. I can try it with the HostLink driver and see if it also works.

[Archie]

Maybe the attached excerpt from the manual is a clue. It says you cannot write to the H area with C-Mode commands while in run mode.

Try changing the PLC to Monitor mode to see if that makes a difference.

[Archie]

This has been confirmed that the H bits cannot be written to in Run Mode using Host Link. The End Code returned from the PLC is 01 which is "Not executable in run mode"

This is only  limitation of Host Link and not of FINS.