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General => Technical support => Topic started by: tobor0216 on May 31, 2010, 10:44:37 AM

Title: Counter
Post by: tobor0216 on May 31, 2010, 10:44:37 AM

I am trying to sense to many time per day my air conditioner runs. I installed a switch in the duct work that has a paddle in it. When the fan turen on the switch is made. The switch is made until the fan turns off.

I want to increment the counter by 1 when the switch is made. The reset the trigger (Input 1) and wait for the next time the switch is mad to increment the counter.

Any Ideas?

I tried the code below


If testbit(Input[1],1)then
C = C+1
Endif

Title: Re:Counter
Post by: support on May 31, 2010, 11:15:02 AM

Is the switch connected to Input1? Or is there a separate "reset trigger" input?

Assuming your fan sensor switch is connected to an input named: fanSwitch:

(http://fanSwitch1.jpg)
Within the custom function FanSWCnt you can put your statement:

C = C+1

which will increment the counter.

If you have a separate reset switch to reset the counter then you can connect the reset switch to another custom function and then within that CF you run the statement:

  C = 0

to reset it.

Title: Re:Counter
Post by: support on May 31, 2010, 11:17:38 AM

The program of course can also be constructed purely out of ladder logic using the [UpCtr] counter. The maximum range in this case is 1 to 9999. You can cascade multiple counters to expand the range. i.e. when first counter reaches 9999 and roll over to 0 it increments another counter. The range therefore increased to 1-99999999 counts.