BOMBARDIER BD-100-1A10, Operating Manual

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HYDRAULICS
Volume 2 Flight Crew Operating Manual May 06/2005
13-01-04
CSP 100-6
REV 2
LEFT AND RIGHT HYDRAULIC SYSTEM (Cont)
The visual quantity indicator is a gauge that shows the hydraulic fluid level in the reservoir. The gauge has marks from zero
to 100% in increments of 10%. The indicator senses the position of the low-pressure piston as a measure of the remaining
fluid volume. The quantity indicator also sends an electrical output signal to the Remote Data Concentrator (RDC), which
shows fluid quantity on the hydraulic synoptic page, and on the copilot’s MFD hydraulic summary page.
The suction shutoff valve is installed in the pump suction port of the reservoir. This shutoff valve is closed by the reservoir
piston when the fluid level is almost empty. This prevents fuel from being pumped into the hydraulic system if there is a
break in a hydraulic line inside the fuel tank.
ECOLOGY BOTTLE
The left and right hydraulic systems each contain an ecology bottle installed in the lower part of the rear fuselage. The ecol-
ogy bottles collect hydraulic fluid leakage from the DCMP shaft seals, PTU seal drain port, and the reservoir bleed/relief
valves. The bottles are transparent in order to see the level of the hydraulic fluid inside.
UNLOADING OF HYDRAULIC PUMP FOR INFLIGHT AIRSTARTS
The engine driven pump incorporates a depressurization circuit to unload the pump and reduce the input torque required
during engine relights. Also when the reservoir fluid temperature reaches 275
°
F, the PSEU will command the FADEC to
depressurize the engine driven pump. The DCMP will also automatically continue providing hydraulic pressure to other
systems after the EDP stops functioning. No action is required of the flight crew, as the above procedures are automatic.
LEFT AND RIGHT HYDRAULIC SYSTEM COOLING
The left and right hydraulic systems require cooling due to heat generated by the EDPs and other heat sources within the
engine nacelle. The left and right hydraulic systems have a fuel/hydraulic heat exchanger in each wing tank.
A thermostatically controlled bypass valve is installed between the heat exchanger inlet and outlet line on each hydraulic
system. The valve controls the flow of pump case drain fluid to the heat exchanger as a function of fluid temperature. It
also acts as a thermal bypass valve if pressure drop through the heat exchanger becomes excessive.
At fluid temperatures above 125
°
F the valve is in the full open mode and routes all incoming fluid through the heat ex-
changer to provide cooling. Below 125
°
F the valve is in the bypass mode and routes all incoming fluid around the heat
exchanger and directly to the reservoir. If 275
°
F is detected for more than 3 seconds, the SOV will close and a L (R) HYD
TEMP HIGH (C) CAS message will be illuminated.
HYDRAULIC RESERVOIR QUANTITY PERCENTAGES
The hydraulic reservoir quantity percentages are displayed in 2% increments on the Summary page and Hydraulic Synoptic
page. When the quantity levels are within normal range (as shown in the table below), the quantity percentages will be dis-
played in green. When the hydraulic systems levels are above or below normal, the percentages will be displayed in white.
Approximately 25% of the fluid is in the landing gear hydraulic lines and actuators when the gear is down, so quantity per-
centages will show lower but usually stay in the normal range. When the gear is retracted, the fluid level percentages will
climb but still stay in the normal range. If the system percentage is less than the normal lower level, it will display the per-
centage in white and it should be serviced prior to flight. If the left system has been over serviced, it may port excess fluid
through the left system reservoir relief valve when the landing gear is retracted. There are no CAS messages associated
with percentages that are above or below normal levels.
LEFT
SYSTEM
RIGHT
SYSTEM
AUXILIARY
SYSTEM
NORMAL
UPPER LEVEL 85% 85% 85%
PERCENTAGES
NORMAL
LOWER LEVEL 30% 40% 20%
PERCENTAGES
V 2