RPM Measure OF Urea

We measure RPM of Urea Bucket with two ways one from VFD and other
from Inductive sensor. Inductive sensor give less reading than VFD.
What is possible reason behind this?
Plz guide

Thanx

The Output of the VFD is frequency not RPM, it doesn't allow for the slip between magnetic field and the rotor or motor and drive pulleys.

To give a better answer we need a lot more information.
What is the expected speed?

>The Output of the VFD is frequency not RPM, it doesn't
>allow for the slip between magnetic field and the rotor or
>motor and drive pulleys.
>
>To give a better answer we need a lot more information.
>What is the expected speed?

If VFD Measure 200 and Inductive sensor measure 180 almost. Rate RPM are 220.

"it doesn't allow for the slip between magnetic field and the rotor or
motor and drive pulleys."What does it mean?

>"it doesn't allow for the slip between magnetic field and the rotor or
> motor and drive pulleys." What does it mean?

The magnetic field rotates at synchronous speed 3600, 1800, 1200, 900 or slower (assuming you have a 60 Hz supply) depending upon how many pairs of poles are in the motor.

The Rotor will turn just a little bit slower depending on how greatly it is loaded, the difference is called slip.

Hi yo'all!

The meter READING 220 RPM needs to be calibrated (0 -100%) to the same SPAN as the sensor and the VFD. From the data given, the RPM Meter which read 220 needs the calibration.The appropriate span (range) would be 0 to 500rpm.

Happy troubleshooting !

PETER MACALUA
PORT ARTHUR TEXAS