Operation Manual – ITW GSE 6400 Tier 3
i) Battery Disconnect Switch
If the unit is not going to be used for a long period of time, open the battery disconnect switch to remove
24 VDC power to the control board and Cummins ECM controller.
DO NOT
open the battery disconnect
switch while the engine is running or within two minutes after the engine has shut down.
3) Starting the 28.5 VDC Generator Set
CAUTION
The unit can deliver up to 2000 amps of current during the starting of an aircraft
engine. This much current will shear the propeller shaft of some aircraft. Therefore,
make sure that the current limit is correctly set for the aircraft that is being powered.
a) Default setup values
28 V Voltage (V):
28.5 VDC
28 V Compensation (V/600A): 0.0 (Set if GPU supplied with cable)
28 V Current Limit (A):
800 A
Output
Mode:
Simultaneous
Fan
Control:
Normal
Plug Temperature:
Normally Open
b) Adjusting the Current Limit
1) The unit remembers the last current limit that was selected. This value will be used whenever
the 28VDC output is turned on. (If the current limit is set too high, the aircraft engine could snap
the propeller shaft. If the current limit is set too low, the engine will take longer to start and
could trip one of the overload limits. See Chapter 1-1 Section 4.d for limits)
2) If the current limit needs changed, use the following procedure:
3) With the unit’s engine running and the 28 VDC power is off, the up or down arrows in the
current limit section can be used to change the current limit value. The step size used for
changing the current limit is set in the Current Limit Step Size setup menu screen.
4) Once the correct value is selected, use the below procedure to start the unit.
OM2254 Rev A
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