Unitronics Samba plc
I am working on a system that uses the High Speed input on a plc to calculate the rpm of a shaft. It is having issues with accuracy and I am reaching out for advice to see if there is a better way to do it.
The machine is a shavings mill. A conveyor feeds chunks of wood and lumber into the mill. The mill is engine driven, but the conveyor has a motor with a VFD so we can vary the speed. The goal is to get maximum product so it is set up so that the speed of the conveyor will adjust according to the speed of the mill. So it will automatically slow down the feed if the mill is getting overloaded or slowing down for any reason.
But the issue if the accuracy of the RPM. Due to the application, we need constant live rpm readout so the conveyor can quickly respond.
There is a prox sensor detecting targets on the mill shaft.
Currently the High Speed Input is set up as Frequency Measurement and returns a value of pulses per second. The pulses per second is multiplied by 60 and that number is divided by the number of targets on the shaft, which results in RPM, but it tends to jump around alot and is not consistent.
Is that the best way to calculate RPM of a high speed input or would you recommend a better method for this application?
I am working on a system that uses the High Speed input on a plc to calculate the rpm of a shaft. It is having issues with accuracy and I am reaching out for advice to see if there is a better way to do it.
The machine is a shavings mill. A conveyor feeds chunks of wood and lumber into the mill. The mill is engine driven, but the conveyor has a motor with a VFD so we can vary the speed. The goal is to get maximum product so it is set up so that the speed of the conveyor will adjust according to the speed of the mill. So it will automatically slow down the feed if the mill is getting overloaded or slowing down for any reason.
But the issue if the accuracy of the RPM. Due to the application, we need constant live rpm readout so the conveyor can quickly respond.
There is a prox sensor detecting targets on the mill shaft.
Currently the High Speed Input is set up as Frequency Measurement and returns a value of pulses per second. The pulses per second is multiplied by 60 and that number is divided by the number of targets on the shaft, which results in RPM, but it tends to jump around alot and is not consistent.
Is that the best way to calculate RPM of a high speed input or would you recommend a better method for this application?