ATR 42 Model : 400/500
GENERAL
HYDRAULIC SYSTEM
P 3
MAY 98
001
1.12
.
10
10.2 CONTROLS
HYD PWR PANEL
Main pumps pbs
Control activation/deactivation of ACW electric motor driven pumps.
ON
(pb pressed in) Pump is energized
OFF
(pb released) Pump is deactivated, OFF It illuminates white.
LO PR The light illuminates amber and the CCAS is activated through the MFC
when the associated pump delivered fluid pressure drops below 1500 PSI
(103,5 bars).
Auxiliary pump pb
Controls operating mode of DC auxiliary pump.
AUTOMATIC (pb pressed in) Pump runs as soon as the following conditions are
met :
- ACW blue pump pressure below 1500 PSI and,
- propeller brake released and,
- gear handle selected DOWN and,
- at least one engine running
OFF
(pb released) Auxiliary pump is deactivated, OFF illuminates white.
LO PR
The light illuminates amber and CCAS is activated when auxiliary
pump outlet pressure is detected lower than 1500 PSI and
functioning conditions are met.
XFEED pb
Controls opening and closure of the crossfeed valve.
OFF (pb released) Crossfeed valve is closed. Both hydraulic circuits are
separated.
ON
(pb pressed in) Crossfeed valve is selected open. Both hydraulic circuits are
connected. ON It illuminates white.
OVHT It
The It illuminates amber and the CCAS is activated when pump case drain line
overheat is detected (T > 121
°
C/250
°
F)
LO LEVEL It
The It illuminates amber and the CCAS is activated when associated tank
compartment fluid quantity drops below 2.5 l (0.67 US gal). The X FEED
automatically closes.
AA
1
2
3
R
4
5
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01/07//2018 REV 1 These notes are not revised after issue For Training Purposes Only
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