AB SLC 5/03 real time clock control

DRThorne

Member
Join Date
Aug 2002
Location
Ontario
Posts
57
I want to start/ stop a motor during certain hours of the day using the clock in a SLC5/03 cpu (1747-L531 OS302)... example: I want the motor to turn on between 0400 and 1600 hours
Do I monitor the S:40 bit in an EQUAL TO/ GREATER THAN instruction or is there a better way to do it?
 
I won't say it's better, but ... if you're not familiar with the LIM (limit) instruction, you might want to take a look at it. The Test value will be the S:40 (real-time clock hour) that you mentioned. Just watch out when entering the value of the High Limit (turn off time) or you might get an unexpected extra hour of run time.

And while you're experimenting with the LIM, pay careful attention to what happens if the value of the High Limit is LESS THAN the value of the Low Limit.
 
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