CONTREX MLP-Drive - Manual (Page 79)

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Offset Mode Analog Setpoint Example
The following example demonstrates Offset mode scaling using analog setpoint:
The lead nip motor on a web has a maximum operating speed of 1800
RPM and is equipped with a 60 tooth ring kit sensor. The follower motor
on the same web matches the line web speed when it is rotating at
1800 RPM. It also is equipped with a 60 tooth ring kit sensor. The
following setpoint is entered as the ratio of the follower web speed to
lead web speed. A dancer pot is placed on a web take-up between the
lead and follower nip rolls. When the potentiometer is in its desired
neutral position, the analog voltage level is 6.0 volts or 60.0% of the
10.0 volt analog full scale. Web operation is optimized by subtracting
15.0% of full scale feedback from the scaled reference when the analog
input is at full scale (10.0 volts).