Operation Manual - Hobart 2400 Compact Power – 120 / 140 / 180 kVA
General Description
Document no. 578.430AB
Page 14 of 75
Aircraft Connector Insertion:
This feature verifies that the 90% switch / split “F” pin in the 400 Hz plug is activated. If not activated,
the respective output cannot be engaged. This also includes a potential free output showing whether the
Aircraft Connector is inserted or not. The feature is valid for ground power units with one or two outputs.
How to bypass/activate the function please refer to section 6.3
For detailed information/connection please refer to section 4.9
Neutral Voltage Supervision (NVS):
The unit is delivered with a jumper wire between the 400 Hz neutral and earth/ground. If the jumper
wire for any reason (eg. Local regulation) is removed, the unit monitors the voltage between the 400 Hz
neutral and earth. If this voltage exceeds 42 V (factory setting), the unit shuts down and reports “NVS
failure”. For change of setting please refer to section 6.3.
Neutral Voltage Displacement Supervision (NVD):
The combination of a grounded converter and an un-grounded aircraft might lead to an energized
aircraft chassis. The reason is the neutral voltage displacement caused by an unbalanced load. In case
the aircraft frame is or will be grounded during operation, a broken neutral might result in sparks as well
as burned ground wires. The neutral voltage displacement of the aircraft chassis is measured as an AC
voltage imposed on the EF interlock signal.
For change of setting please refer to section 6.3.
Earth Leakage Supervision (ELS)
In systems where the 400 Hz neutral is grounded and there is a break of the cable’s 400 Hz neutral, the
ELS system monitors the residual current in the internal neutral /earth connection. The supervision will
shut down the unit in case the residual current reaches the pre-set level.
For change of setting please refer to section 6.3.
OM2252
Rev 0 December 15 2016
