Others 687 Transformer Rectifier Unit
EUROPE (Western and Northern)
Transformer Rectifier Unit
designed for the starting and servicing of civil and military aircraft with 28 volt
DC systems. The unit is suitable for hanger or apron use and is trolley mounted.
The unit operates from a 50 or 60 cycle, 3-phase main supply.
The bridge rectifier consists of silicon diodes mounted on extruded aluminium
heat sinks. Cooling is provided by an electrical operated fan.
Class ‘B’ insulated is used throughout the transformer windings.
The rectifier d.c. is smoothed before passing to the output contactor.
Push buttons operate the output contactor to supply 28 volt d.c. to the output
An interlock relay, which operates via sensing leads in the output cable, prevents
the contactor from being closed if the cable is not connected to that aircraft.
Input: 380 to 440 volts, 3 phase 50 or 60Hz
Output: Continuous at 28 volts d.c. Continuous: 400 Amps
Intermittent output for 15 seconds at 24 volts d.c. four times in two minutes.
OVERALL DIMENSIONS (approx) – Trolley Mounted
Length: 1.68m (66ins) Width: 0.94m (37ins) Height: 1.19m (47ins) Weight: 444kg