RJ150-30 / Operations and Maintenance Manual
Mobile Aircraft Air Conditioner
Trailer Mounted, Cool Mode Only
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SECTION 1 - 1
JANUARY 20, 2004
PAGE 8
F. Low Fuel Detection/Shutdown (Optional):
Fuel level signals from the Fuel Level Sender (FLS) are routed to the low fuel
level control circuitry, which includes a Fuel Level Switch (FS1), and control
relays CR5 and CR6. When a low fuel level condition (Warning Level) is
detected by the Fuel Level Switch (FLS), the control relay (CR5) energizes a
warning beacon (DS2; BLUE) mounted on the unit top canopy. Upon
detecting Shut-Down Level low fuel condition, the Fuel Level Switch (FLS)
energizes control relay CR6 to remove the genset START circuit and causing
the genset engine to shut-down after a three (3) minute cool-down. The low
fuel detection circuit receives unit battery (24VDC) power and is protected by
a 5-Amperes (5A) fuse (FU9). Control circuitry is located in a junction box
mounted to the unit frame inside the right rear canopy panel. (See Figure 5)
Figure 5. Low Fuel Circuit Junction Box
(Shown with access cover removed)
Fuse 5A (FU9)
Low Fuel
Warning Relay
(CR5)
Low Fuel
Shutdown Relay
(CR6)