Operation Manual - Hobart 2400 Compact Power – 120 / 140 / 180 kVA
General Description
Document no. 578.430AB
Page 9 of 75
Output Transformer (T2/T4):
The output transformer ensures galvanic separation between input and output. It also transforms the
voltages from the Inverter Module
into the required aircraft voltage (3 x 200/115 V). The filter choke
for the output AC-filter is an integral part of the transformer.
AC Filter Capacitors (C7-C9 / C10-C12):
The harmonic content of the inverter voltage is further reduced by means of the AC Filter, resulting in a
total voltage distortion of less than 2%. In addition to the filter choke (integrated into the transformer)
and the AC capacitors, the ground power unit is equipped with an RFI-filter that reduces the high
frequency emissions from the ground power unit and from the aircraft.
Output Contactors (Q4/Q5):
The ground power unit is equipped with a 3-phase output contactor per output. The contactors are
engaged at start-up of the corresponding output and are disengaged when the corresponding stop button
is activated or a system error occurs. If the interlock voltage, provided by the aircraft, is not returned to
the ground power unit within the delay settings (refer to chapter 6.3), the corresponding contactor also
disengages.
Interface Board (A2):
The purpose of this board is to interface between the Control Board and the rest of the ground power
unit. The interface module includes the following functions:
•
Interface to the Display Board (CAN Bus, 24 VDC and EPO (External Emergency Stop))
•
Fuse (F1 & F2) of the 24 VDC for I/O connections
•
Fuse (F3) for Display Board (A3) and Operator Keyboard (A4)
•
Fuse (F4) of the 24 VDC for interface
•
Fuse (F5) PWM control (X15) of fans (M1-M2)
•
Fuse (F6) PWM control (X16) of fans (M3-M4)
•
User EPO input (X6)
•
Measuring transformers for supervision of the 400 Hz output 1 voltage (X28)
•
Measuring transformers for supervision of the 400 Hz output 2 voltage (X27)
•
Interface for gate drive situated at the Inverter Module (PM1) via GD1 (X10)
OM2252
Rev 0 December 15 2016
