OM-2245 / Operation and Maintenance Manual
ITW GSE 4400 / 400 Hz. Generator Set
March 15, 2015
Chapter 1-3
Page 5
3) Active Rectifier Unit (ARU) – 28.5 VDC Power Supply
CAUTION
The ARU can deliver up to 2,000 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.
1) Setting the Current Limit
a) The Setup menu is used to change the default current limit value. This value will be used
whenever the 28VDC output is turned on.
i)
Refer to section 4.0.2 for instruction in how to get into the Setup Menu. Use the up or down
arrow buttons to scroll to the 28V Current Limit menu item and press
Ɣ
twice.
ii)
Use the up or down arrow buttons to change the default value to the desired current limit for
the aircraft being powered.
iii) Press
Ɣ
to accept the changed value as the new default value.
b) If the current limit only needs to be changed for a one time use, use the following procedure:
i)
With the unit’s engine running and the 28 VDC power is off, the right or left arrows can be
used to change the default current limit value. (400, 600, 900, 1200, 1500, 1800, & 2000)
ii)
Once the correct value is selected, use the below procedure to start the unit.
Note: To ensure hassle-free starting of the aircraft engine, the current limit function is delayed 0.7 seconds.
With the engine running and DC
power OFF, press the
“Right
arrow”
to temporarily increase the
DC current limit.
With the engine running and DC
power OFF, press the
“Left arrow”
to temporarily decrease the DC
current limit.
