POWER DISTRIBUTION PANEL (PDP)
Two PDP (PDP1 and PDP2) are installed in the forward area of the cabin
roof.
PDP’s are cabinets that contain the power contactors and the control circuits
used to:
• connect the aircraft electrical power sources (generators and batteries)
to the LH and RH distribution bus bars via the MAIN LOAD BUS 1 and
MAIN LOAD BUS 2, respectively
• check and connect the external power source to the aircraft distribution
bus bars
• control the Main bus tying (BUS TIE Contactor)
SHUNT
Four shunts are used to pick up a signal proportional to the current flowing
to/from electrical power sources (main and auxiliary batteries, startergenerators
1 and 2) to display the relevant electrical load on indicators.
DC CURRENT TRANSFORMER (CT)
Four current transformers are used to detect the differential changes in DC
current feeding lines, routing a signal to the GCU which de-energizes the
line contactor when an overcurrent or a short-circuit is detected.