Tronair 112850D0000, Operation & Service Manual

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28.5 VDC Ground Power Unit
Models 112850S0000 112850S0100 112850S0200
112850D0000 112850D0100/AV 112850D0100-A5 112850D0200
112860S0000 112860S0100 112860S0100-A4 112860S0100-A6 112860S0200
112860D0000 112860D0100 112860SD100-A5 112860D0200 112860SD200-A5
06/2013 | Rev. 03 Page | 6
3.0 SYSTEM DESCRIPTION (continued)
3.8 CONTROL PANEL
There is a local Control Panel on the cubicle door of the converter which contains a light emitting diode (LED) indications, E-
Stop, and meters
The LED’s on the control panel are red, green and yellow. They are also bi-functional, able to display as steady state or
flashing. With combinations it is possible to display healthy state, non-operational, abnormal and fault conditions.
Green steady state .......................... Running or switched on
Yellow flashing ................................ Warning
Red flashing .................................... Hardware fault (circuit breaker, contactor, etc.)
Red steady state ............................. Abnormal condition (e.g. mains fault, overload, etc)
The Red indicating LED is for fault conditions that are recoverable, such as overload. These faults are displayed as a Steady
Red light. Faults requiring maintenance attention, such as CB open, are displayed as a Flashing Red light.
3.8.1
Operator Controls
Push buttons “ON” and “OFF” control the converter operations.
3.8.2
Emergency Stop
In an emergency, to immediately open the unit’s input and output contactors, the large red button on the Control Panel must
be pressed.
IMPORTANT
Bear in mind, however, that the mains in feed is still “live”. The converter can only be isolated by using suitable
external means such as padlocking the supply breakers of the incoming distribution board.
3.9
OVERVIEW OF 28V DC GPU COMPONENTS
The modules and components of the individual sizes of the 28V DC GPU are shown in the outline drawings in this section. The
sizes and arrangement of the modules and components shown vary slightly according to the power rating and version of the
28V DC GPU sets.
Abbreviation Description of Component
MOD 1 Rectifier SCR
PCB 2 Firing board
Interface board
K-1 28V Relay
K-2 28V Relay
T2 Power supply transformer
T2 Power supply transformer
T3 Power supply transformer
PAN 1 Control panel
CAPS Filtering capacitors
FAN 1 Cooling Fan
R 1 Load resistor
CB 1 Input circuit breaker
CB 2-6 Protective circuit-breaker control voltage
SW 5 Current limit POT
T 1 Isolated 3 phase input transformer
AUX 1 Transformer auxiliary voltage
AUX 2 Transformer auxiliary voltage
CONT 1 DC output contactor
CONT 2 DC output contactor