- General Electric Computer Accessories User Manual

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• Chapter 3 Paramters/Functions Innovation Series Medium Voltage GP Type - G Drives GEH-6385
Function outputs
Variable Description
Full flux request A request to enable the bridge and pre-flux the drive. This
signal is the output of Full flux req sel and Full flux req, lan.
Full flux
command
Internal sequencer command to enable the bridge and pre-
flux the drive. This output requires that the Ready to run
permissive string be satisfied. The details of the logic which
forms this signal is shown in the sequencer diagrams.
Standby
command
Internal sequencer command to enable the bridge, pre-flux
the drive and enter an adaptive full flux standby mode. This
output requires that the Ready to run permissive string be
satisfied.
This command is generated only when the drive is using a
Tachless motor control and Enb adaptv full flx is set to Yes or
Flying restart is set to Locked shaft restart. The standby mode
is used to measure the value of motor parameters that are
critical to Tachless motor control operation. The details of the
logic which forms this signal is shown on the sequencer
diagrams.
Function configuration
Parameter Description
Enb adaptv
full flx
This parameter is specific to the Tachless motor control algorithm
and is associated with Full flux request mode operation. If this
parameter is set to Yes, the drive control will track motor
resistance continuously during Full flux request mode. This will
ensure optimal low speed control performance and optimal torque
per ampere capability when the Tachless control drive resumes
normal running condition.
The Vector Tachless drive cannot keep the motor energized at
zero speed in (Full flux request mode) for an extended period of
time (measured in 10’s of seconds) without malfunction unless the
parameter Enb adaptv full flx is set to Yes (see caution below).
Otherwise, the drive must be stopped and restarted when it is
desired to move.
When the Tachless drive is stopped, there is a requirement to wait
for the motor flux to decay (1 to 20 seconds, depending on motor
rotor circuit time constant) before restarting the drive. Otherwise,
a Run cmd w high flux alarm will occur and the drive will be
blocked from starting until the flux has decayed to a lower level
(2% rated).
When parameter Enb adaptv full flx is set to Yes, any externally
induced shaft motion (even very slight motion) will cause the
drive to malfunction. Please do not activate this function if the
motor shaft can be rotated by its load while in Full Flux mode.
Please see also other cautions on applying Tachless Control
drives as specified under the parameter, Motor ctrl alg sel.
Related diagrams
• General Sequencing #3 (GenSeq_3)