Cycles Per Minute Logic

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Thread Starter

C. Nelson

I am trying to display cycles per minute of machine, I am using DL-260 from automation direct. I would like to show ??.? on the display. I would like to update the value every 10 sec. or so.
 
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Steve Bailey

You could count the number of cycles in ten seconds and multiply that number by 6.

Or you could measure the time (t) required to complete x cycles. Then cycles per minute would be (x * 60)/t
 
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Curt Wuollet

Think about that for a second.
XX.X cycles per minute with a 10 second update which is 6 per minute. Allowing 10 seconds, even if you are talking about 10's of cycles per
minute, you can't directly get 3 place accuracy. What you may need to do is a running average over 10 minutes or some such chicanery. I would like to see that fractional part/minute with sample time of less than a minute.:^)

Regards

cww
 
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Michael Griffin

On January 16, 2003 02:11 pm, C. Nelson wrote: <clip>
> > I am trying to display cycles per minute of machine, I am using DL-260
> > from automation direct. I would like to show ??.? on the display. I
> > would like to update the value every 10 sec. or so.
<clip>>

Some people like to see machine cycle time (rate technically) in parts per hour. This however is just determined by measuring the time to process a single part and converting seconds per part to parts per hour. Parts per minute could be calculated similarly:

60 / (seconds per part) = (parts per minute)

If you rescale this as 6000 / (10th's of a second per part), then you can do the calculation as an integer and just insert the decimal in the correct spot in the display field. This is especially easy if your timer happens to have a 100 msec time base, since you can use the accumulated time value directly.

For example, if the cycle time for one part was 6.5 seconds, and the timer time base was 100 msec. then 6000 / 65 = 92 . The display could then insert a decimal place to show this as 9.2 parts per minute.

If you follow this approach, then you would simply update the display after each part.

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Michael Griffin
London, Ont. Canada
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