Retentive On-delay Timer for S7-300

[Ken M]

GTX

Go to the TI-S7 Converting Blocks folder in the STEP7 Standard Library. There you will find FC80 named TONR just as Daniel Chartier mentioned. Use it instead of T13 and T14. It has exactly the functionality you've described.

I don't have the software here in front of me at present, but I think one parameter that is required is named Delta_T. This timer uses the duration of the previous OB1 cycle time as its time base. If you are using the FC80 directly in OB1, you'll get this value as a TEMP variable in OB1 named OB1_PREV_SCAN. If you want to use FC80 in a nested block you will have to put a single line of code in OB1 to copy that OB1_PREV_SCAN variable to some globally accessible address (MWxxx or DBy.DBWzzz) and then use that as the Delta_T.

It's really simple when you get it.

Regards

Ken M.

 

[PLC_Time]

All...Trying to revisit this issue. Rookie Siemens programmer (AB for many years). I have tried in simulation mode to get this to work based on the tips in this thread. Due to the length of the timer (24hrs) I cant use the S_ODTS. Its a SIemens S300, thus dont seem to have the FC80. I have spent a lot of time on Google and here to find an exact solution for what i need. Also, I cant use Counters because my value is too large for that many ms in a day. I need things to be within a few seconds for the day (thus I cant count off of minutes for example should the machine start and stop a lot). Yes I know the PLC itself could be off that far. Can someone PLEASE provide a code example in SIEMENS?

 

[Lare]

You can use Dint data type and add block with time pulse.
If you incerement every second Dint-variable, thne max time is 2147483647 seconds, that is 68 years.
Even with 100ms pulse it can still count 6,8 years.

 

[Alfons Gessl]

Hallo Eduardo
the 0 voltage retentive you set at the hardware config of the PLC range from T0 - 16 is standard you can change that as you wish up to max of your PLC
all timers are retentive if a logical input is programmed at the R = Reset input of your Timer

Regards
Alfons