- General Electric Computer Accessories User Manual

GEH-6385 Reference and Troubleshooting, 2300 V Drives Chapter 3 Paramters/Functions •
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• 3-45
Flux Curve
The Flux Curve describes the relationship between the induction motor voltage and
current. Specifically, each point of the curve specifies the voltage that is measured at
the motor terminals for a particular excitation current, under no load conditions at the
nameplate frequency.
Function configuration
The Flux Curve consists of five voltage and current points. Two parameters are
associated with each point. The following table lists the parameters that configure the
Flux Curve.
Parameter Description
Flux curve voltage 1 No load voltage for data point 1. RMS volts
Flux curve voltage 2 No load voltage for data point 2. RMS volts
Flux curve voltage 3 No load voltage for data point 3. RMS volts
Flux curve voltage 4 No load voltage for data point 4. RMS volts
Flux curve voltage 5 No load voltage for data point 5. RMS volts
Flux curve amps 1 No load current for data point 1. RMS amps
Flux curve amps 2 No load current for data point 2. RMS amps
Flux curve amps 3 No load current for data point 3. RMS amps
Flux curve amps 4 No load current for data point 4. RMS amps
Flux curve amps 5 No load current for data point 5. RMS amps
The parameters listed above specify the curve if they contain meaningful values. If
all the parameters are set to <No Value>, then the control uses the curve measured
during Motor Control Tuneup.
Function description
Often the motor data sheet contains four or five voltage and current measurements
that specify the Flux Curve. The voltage points are generally labeled "VNL" and the
current points "INL".
If five data points are available on the motor data sheet, they can be entered directly
into the configuration parameters. Flux curve voltage 1 and Flux curve amps 1
represent the smallest voltage and current, and Flux curve voltage 5 and Flux curve
amps 5 represent the largest voltage and current.
If fewer than five data points are available on the motor data sheet, the highest data
points should contain meaningful values and the lowest data points should be set to
<No Value>. To reset one of the parameters to <No Value>, highlight the value and
press the Delete key.
If the curve data is not available, all the configuration parameters should be set to
<No Value>, and the Flux Curve should be determined using the Motor Control
Tuneup.