POWER CONTROL MODULE – GENERAL
Each one of the two Power Control Module (PCM) consists of the following
main components:
• a reservoir inside which the hydraulic fluid is separated from the air
• three fluid level microswitches
• a visual hydraulic fluid level indicator located on the back side of
reservoir
• one Pressure and one Return filter assemblies which provide filtration
of the hydraulic fluid. Only the Return filter is provided with a by-pass
valve to allow hydraulic fluid recirculation in case of filter clogging. Both
Pressure and Return Filters are provided with a differential switch
which activates when filter is clogged. Pressure and/or Return Filter
clogged condition is shown on the hydraulic synoptic
• one filter clogged visual indicator for each filter. The mechanical
indicator (RED POP-OUT) once actuated remains extended until reset
manually (position hidden from view)
• the Flight Controls (FC) circuit shut-off valves (identify as SOV1 and
SOV2 on the hydraulic synoptic) permit to isolate the flight controls
from the hydraulic circuit in case of system overheating
• the utility circuit shut-off valves (identify as UTIL SOV1 and UTIL SOV2
on the hydraulic synoptic) permit to isolate the utilities from the
hydraulic circuit in case of leakage. These valves are automatically
controlled by the fluid level microswitches inside the reservoir
• pressure sensors and pressure switches
• pump suction, pressure and drain lines ports
• flight controls pressure and return circuit lines connection ports
• pressure and return ground equipment connection ports
PCM1 supplies hydraulic pressure to the system 1 while the PCM2 supplies
pressure to the system 2.