- General Electric Computer Accessories User Manual

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• Chapter 3 Paramters/Functions Innovation Series Medium Voltage GP Type - G Drives GEH-6385
The table below lists how the parameters define the center speeds of each of the
speed avoidance zones.
Speed Avoidance Zone Center Speed
Positive zone 1 Critical speed 1
Positive zone 2 Critical speed 2
Positive zone 3 Critical speed 3
Negative zone 1 -1 x Critical speed 1
Negative zone 2 -1 x Critical speed 2
Negative zone 3 -1 x Critical speed 3
The hysteresis is the same for all of the speed avoidance zones. For each of the speed
avoidance zones, the Critical Speed Avoidance function prohibits the speed reference
from taking on values between [Center speed - Critical speed hys] and [Center speed
+ Critical speed hys], where Center speed is defined by the table above. The total
width of each of the speed avoidance zones is 2 times Critical speed hys.
Related diagrams
• Critical Speed Avoidance (CrSpdAvd)
Local Speed Reference
The Local Speed Reference forms a speed reference signal from the local source (the
DDI/keypad).
Function inputs
The following table specifies the input variables to the Local Speed Reference
function.
Variable Description
Local inc command Signal that is True when the DDI speed increment button
is pressed.
Local dec command Signal that is True when the DDI speed decrement button
is pressed.
Jog request Sequencer request to jog the drive.
Function outputs
The output of the Local Speed Reference function is a local speed reference. This
becomes the speed reference used by the Speed Reference Generation function if
Local mode active is True.
Function configuration
The following table specifies the configuration parameters for the Local Speed
Reference function.
Parameter Description
Local speed Initial value of local speed reference. RPM
Local jog speed
Jog speed that becomes the local speed reference when Jog
request is True. RPM
Local Inc/Dec
rate
Rate of change of the local speed reference. RPM/second