Woodward 2301E-ST, Installation And Operation Manual

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Manual 26694 2301E-ST
Woodward 98
Symptom Cause Solution
Prime mover overspeeds
after operating at rated
speed for some time
(continued).
2301E-ST control. Control the prime mover manually at
rated speed. If the Turbine Speed
reading in the Display Menu does not
match external indicators, the control is
not configured properly. When the
turbine speed value is greater than the
speed reference value, the output
voltage should be zero. If speed range is
correct for the application, replace the
control.
Prime mover will not
stabilize at rated no load
speed. The instability may
occur at no load or it may
vary with load Control may
be erratic.
2301E-ST control. Adjust PROP GAIN, INTEGRAL GAIN
and DERIVATIVE RATIO as described
in “Adjust for Stable Operation” and
“Dynamic Adjustment” in Chapter 3.
Speed reference controls. Check display menu. The speed
reference value should be constant. If
speed reference is erratic, check remote
input (if used), intermittent raise/lower
contact inputs. The speed bias sum at
no load should be constant.
Improper linkage adjustment. Make sure that actuator moves
approximately 2/3 of its travel from no
load to full load. Be sure linkage is linear
on turbine, diesel and steam-injected
prime movers. Be sure linkage is non-
linear on carbureted prime movers.
Refer to actuator manual for proper
installation.
Necessary external wires not properly
shielded.
Electrical noise, caused by wiring
carrying an ac voltage, stray magnetic
fields from transformers, etc., can be
picked up by improperly shielded wire.
Noise will cause instability if picked up
by lines associated with the amplifier
summing point such as external speed
trim, paralleling lines, droop contact,
magnetic pickup lines and synchronizer
input. The following tests will isolate noise and
interference.
Do not perform these tests in other
than single-unit operating
configuration.
Verify that the switchgear frame,
governor chassis and prime mover have
a common ground connection.
Temporarily remove the battery charger
cables from the control battery system.
If the prime mover operation is
significantly improved by these
modifications, replace the wiring one at
a time to locate the source of the
trouble.
External wiring may require additional
shielding or rerouting from high-current
lines or components.
If the problem cannot be resolved by
these checks, it will be necessary to
remove the 2301E-ST from the
switchgear. Temporarily mount it next to
the prime mover and connect only a
battery, magnetic pickup and actuator to
the control (use a separate battery
placed next to the prime mover).
Released