Hello,

Possible solution:

1 step: After PLC restart (in OB100) you save the last value of couner into variable:

LAST_VAL := Countervalu_IVERT

2. step: You initialize the FM450 counter module with that LAST_VAL

3. step: Now counter starts count from that preserved value. Done.

PS: changing FC to FB was not necessary in my opinion. 

Hello,

Have you seen this link:

How can you retain the counter value of counter modules (6ES7350-1AH03-0AE0, 6ES7350-2AH00-0AE0, 6ES7450-1AP00-0AE0) after a STOP to RUN transition of the CPU?

Best regards,

Wizard

Hello ZHK,

Thank you for answering.

That is somewhat similar to what I also was planning to try when I get access to the machine tomorrow.

Please see a screenshot from added logic in OB100.

The initializing (Network 1 ) has been there all the time but I have added NW 2 and NW3. The plan is to delete NW3 if NW2 does the trick.

Should the value be moved into the register before or after the initializing? 

Which remanent value could be moved into the FM450 DB if the "last value" is not stored in a instance DB?

ZHK

Hello,

Possible solution:

1 step: After PLC restart (in OB100) you save the last value of counter into variable:

LAST_VAL := Countervalu_IVERT

2. step: You initialize the FM450 counter module with that LAST_VAL

3. step: Now counter starts count from that preserved value. Done.

PS: changing FC to FB was not necessary in my opinion. 

Hello,

Have you seen this link:

How can the counter values of compact CPUs and of the FM 350/FM450 counter module be made available again after a power failure?

Best regards,

Wizard

xmnj

Please see a screenshot from added logic in OB100.

The initializing (Network 1 ) has been there all the time but I have added NW 2 and NW3. The plan is to delete NW3 if NW2 does the trick. 

Hi,

I strongly reccomend you to follow Wizard's solution. That is really straigtforward.

Answering your question - counter module initialization does not work that way. First you have to prepare LOAD_VAL, then you trigger the command for initialization.

Hello Wizard,

Thank you for answering.

Please see the screenshot.

I am not sure exactly how to use the function - please correct my thinking:

In OB100 where the FM450-1 is already initialized today I need to send the retained counter value to the card DB (on the card parameter LOAD_VAL which is a DINT).

But do I need to have the network with the move block before or after the (already existing) initialization?

Do I need to activate a (boolean) trigger to load the retained value into the counter card DB so it will start counting from this value?

The initialization (since it is only done when restating) is in OB100 while the control counter module (CNT_CTRL) is in FB12 which is running continuously. The L_DIRECT pin is on the CNT_CTRL module and this is used to reset the counter (to zero) by pushing a button.

Wizard

Hello,

Have you seen this link:

How can the counter values of compact CPUs and of the FM 350/FM450 counter module be made available again after a power failure?

Best regards,

Wizard

Hello,

Use the function in OB100.

You put retained value in Load_val and with trigger, you can transfer it to card.

It can be behind initialization.

Best regards,

Wizard