Manual 02007
DSLC Digital Synchronizer and Load Control
Woodward
93
Problem Probable
Cause Action
DSLC control doesn't
load to specified base
load
Either the phase currents or the
phase voltages are improperly
calibrated
Check the phase currents and voltages (Menu 6)
and properly calibrate.
A proportional dc speed error
exists on the speed control unit
(no-load speed not set to match
bus frequency)
Adjust rated speed of speed control unit**, or
change to integrating load control***.
Unit unstable in the
Process control mode
Load control set for integrating
control instead of proportional
as specified by manual
Unload and set unit up for proportional load
control (Menu 2).
Process control dynamics are
improperly set up
Go through the Process Control Adjustment
procedure in Chapter 3.
Unit unstable in the
VAR/PF control mode
VAR/PF control dynamics are
improperly set up
Go through the VAR/PF Control Adjustment
procedure in Chapter 3.
Cross-current compensation
installed on voltage regulators
Remove cross-current compensation from the
voltage regulator circuit.
Unit carries improper
proportion of load
during isochronous
load sharing
Rated load set point (Menu 2) at
wrong value
Set the rated load to proper value for the
generator (see the generator technical manual).
A proportional dc speed error
exists on the speed control unit
(no-load speed not set to match
bus frequency)
Adjust rated speed of speed control unit**, or
change to integrating load control***.
** NOTE 2
—If DSLC control loads the generator to a higher value than specified by the
base load set point (Menu 2), lower the rated speed set point of the speed control unit until
proper loading is obtained. If DSLC control loads the generator to a lower value than
specified by the base load set point, raise the rated speed set point of the speed control
unit until proper loading is obtained.
*** NOTE 3
—Changing load control modes from integrating to proportional or vice-versa
while the generator is loaded may cause temporary instabilities and is not advised.