Production Rate through PLC without floating point

[Tim]

Im trying to show the production rate of a machine on a touchscreen. The problem I am having is the Mitsubishi PLC I am currently using does not do floating point math. What I am trying to do is get a sample every 5 minutes on how many parts the machine has produced. Then I take that value and divide it by the amount of parts that it should have produce and then multiply that number by 100 to get my percentage.

My problem is that the PLC I am using does the division, but will not show anything but a whole number. Example... Rate is 3 parts every 5 minutes. If 2 parts are produced, I am taking that value "2" and dividing by 3 which should give .666666 and multiply by 100 to get 66 percent.

It might just be impossible, but I just had to ask if there were any work around solutions.
Thanks
Tim

 

[SimonGoldsworthy]

The most obvious answer is to multiply by 100 first, and then do the division for the sort of numbers you are talking. You may need to do some comparisons to decide which order to the arithmetic in to keep the results as accurate as possible. Is your integer arithmetic limited to 16 bits or is 32 bit available ?

 

[Tim]

Simon,
Hey thanks for the reply. That will work just fine, Monday mornings I need a kick in the butt to get going.

 

[Sliver]

I usually use the HMI to scale if you want to view decimal values

ei. PLC value 952 represents 95.2, HMI does the divide by 10.

Brian.