Struggling_forward
Member
to activate and de-activate function say at 8am every morning?
On a S7-300, how do you use the clock
- Thread starter Struggling_forward
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TurpoUrpo
Lifetime Supporting Member
Look at time of day interrupt OBs (10-17), you can find them on help.
Last edited:
ivo.maenen
Member
- Join Date
- Nov 2003
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Use one of the special OB's. Go to the HW-configuration and activate the OB, think it is called 'time-of-day'. Sorry, but I do not remember the OB-number.
Then program the reaction of the OB. The OB will run automatically, no need to call it in OB1. Send it to the cpu. But watch out the 'time-of-day'-OB is only one cyclus active.
Then program the reaction of the OB. The OB will run automatically, no need to call it in OB1. Send it to the cpu. But watch out the 'time-of-day'-OB is only one cyclus active.
Struggling_forward
Member
OP
Where is the system time word?
You should use system function "READ_CLK" (I dont know number), the output from it is data type DATE&TIME (you can put it to temporary).
After that you have to use "DT_TOD" (it like Date&Time to Time of day converter) so the input is DATE&TIME and output TIME_of_DAY.
After that comprataror IF TIME_of_DAY > TOD#8:0:0.0 (constant of TOD) = deaktivate output !
After that you have to use "DT_TOD" (it like Date&Time to Time of day converter) so the input is DATE&TIME and output TIME_of_DAY.
After that comprataror IF TIME_of_DAY > TOD#8:0:0.0 (constant of TOD) = deaktivate output !
L D[AR2P#0.0]
Lifetime Supporting Member
Here's an example project that allows you set up 16 different TOD's in a DB. As each TOD is reached , a bit in the DB comes on for one scan which you can then use to turn things off/on etc. I've simply used a counter in my example for test purposes.
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