How would you use Compute (CPT) instruction to select the 2 youngest pump in terms of

piscis

Member
Join Date
May 2003
Posts
241
What the formula will look like? Assuming that all of the 3 Pumps running time (in Minutes) are stored in N7: 1 / N7: 2 and N7: 3. How would you use Compute (CPT) instruction to select the 2 youngest pump in terms of minutes running?

Thanks in advance for all your suggestion.


Andy
 
Why cant I get this post out of my head? WOW theres lots of ways to do this with Math instructions but to do the whole thing with one CPT instruction seems impossible. Maybe to get the one shortest running pump but to get the 2 shortest running pumps seems impossible. But then again, Im no rocket scientest for sure.

Good luck.

Bob
 
bobwithdana:


Thanks anyway I guess my only option is this. Plewase let me know if there is a better way.


thanks


untitled.jpg
 
Pump Test

Here is the basic logic. You will have to add logic to latch on pumps when you get a start condition. I ran it on my SLC so it all checks out.
This was an interesting problem. I myself don't know how to do it other than LES or LEQ blocks.
 
Mark Buskell:


I tested your solution and worked great.

Thanks for the input. This goes to show that there are many ways to achieve the same goal.

Thanks again.
 

Similar Topics

I am trying to add 9 DINT values with the CPT instruction in ControlLogix and I keep getting errors. I am just choosing each tag with an add...
Replies
13
Views
2,318
I am using a legacy Allen Bradley PLC5/40E Series F CPU Having issue with compute instruction syntax with the expression Doing a divide by...
Replies
7
Views
1,762
I've got a print-out of old code (PLC-5/250) that I am trying to decipher. I am hung up on an expression in one of the compute blocks. The block...
Replies
7
Views
3,107
I have written control logic for several situations recently where I have used a compute statement instead of a PID loop. My statement looks...
Replies
11
Views
3,567
PLC: Compact Logic 1100 series b RS Logix 500: version 8.40 Issue: No compute Instruction, it is greyed out and I can't use it. Why? Thanks
Replies
6
Views
2,166
Back
Top Bottom