Woodward DSLC, Installation And Operation Manual, Page: 48 / 114

DSLC Digital Synchronizer and Load Control Manual 02007
42 Woodward
Without Load Bank
Use this procedure for droop setting when an artificial load bank is not available.
WARNING—CT/PT PHASING
Operation of the engine/generator set with incorrect CT and PT phasing
could cause serious injury or damage to equipment. If the load on the unit
increases rapidly when you close the breaker, immediately open the breaker
and shut the unit down. Check the phasing of the CTs and PTs. DO NOT
permit the unit to continue to pick up load or to operate the system without
correcting this condition.
1. Select Menu 2 and the Load Droop set point. Set to the desired value or use
5.0%.
NOTE
The load droop setting is approximate as it depends on actual gain of the
input circuits of the engine speed control.
2. Open the isoch/droop switch in series with the CB Aux contact input to
terminal 47 of the DSLC control. If such a switch is not installed, temporarily
remove the connection to terminal 47.
3. Calculate the engine speed required to pick up 50% and 100% of rated
load.
Example: Rated frequency = 60.0 Hz
Desired droop = 5% (0.05) or 3.0 Hz
Desired test frequency = 60.0 Hz + %Load x 3.0 Hz
(at 50% [0.5] load) = 60.0 + 0.5 x 3.0 = 61.5 Hz
(at 100% [1.0] load) = 60.0 + 1.0 x 3.0 = 63.0 Hz
4. Use the raise and lower load inputs to set the desired speed with the
generator circuit breaker open. Record the speed bias output percentage at
the engine speed required to pick up 50% and 100% load.
5. Use the Load Raise and Load Lower inputs (terminals 53 and 54) to both
manually synchronize to the bus and increase the engine load to 10%.
6. Verify correct load sensor operation by observing for correct voltage,
current, and power readings on Menu 7. If incorrect load sensor operation is
observed, verify configuration values on Menu 6, phasing, and other wiring
connections to the DSLC control.
7. Increase the engine speed setting to increase load. When the speed bias
output reaches the value required for 50% load as measured in step 4, trim
the Load Droop set point for 50% load.
8. Increase the engine speed setting to the speed bias output value required
for 100% load as measured in step 4. Trim the Load Droop set point to get
100% load.