mrtweaver
Member
I was wondering, what would be considered the best rule of thumb when it comes to PLC scan time versus input speed time?
An example would be measurement wheel, the measurement wheel provides 12 pulses per revolution, this translates to 1 pulse = 1 inch, the machine runs 243 feet per min, when all the math is dont it equates to about 1 pulse per 20mS. So if the PLC scan time is 20mS that would be bad because it would most likely miss pulses. So what would be the optimum speed at which the PLC should scan in order to keep up with the input?
Thanks and have a great day.
An example would be measurement wheel, the measurement wheel provides 12 pulses per revolution, this translates to 1 pulse = 1 inch, the machine runs 243 feet per min, when all the math is dont it equates to about 1 pulse per 20mS. So if the PLC scan time is 20mS that would be bad because it would most likely miss pulses. So what would be the optimum speed at which the PLC should scan in order to keep up with the input?
Thanks and have a great day.