RJ150-30 / Operations and Maintenance Manual
Mobile Aircraft Air Conditioner
Trailer Mounted, Cool Mode Only
______________________________________________________________________________
JANUARY 20, 2004
SECTION 2 - 4
PAGE 7
Figure 7
Item No.
Description
Function
9
Cooling Temperature Display
Module (TDM2)
Displays ambient air temperature sensed by the ambient
air Remote Temperature Detector (RTD-2) sensor
probe. Pressing push button on unit will display ETC2
setpoint.
10
Cooling Mode Position
Reference Potentiometer (P1)
Airflow control. Sets the position of the airflow damper as
a percentage of open (maximum flow).
Factory setting: 70% open.
11
Fuse (FU4)
Protection for damper motor actuator circuitry.
Rating: 1 A
12
Time Delay Relay (TDR1) -
Defrost Timer
Provides timing control for compressor defrost cycle.
Upper timer sets defrost cycle frequency. Normally set to
one (1) hour.
Lower timer sets defrost timer duration. Normally set to
1.5 minutes.
13
Voltage-Phase Monitor (PM1)
When configured for use, provides generator output
surveillance for voltage and phase loss. Integral contact
(s) close when acceptable voltage and phase rotation
are established.
14
Fuse (FU3)
Over load protection for phase monitor (PM1).
Rating: 10 A
15
Fuses (FU1, FU2)
Over current protection for control transformer (T1).
Rating: 2 A
16
Control Transformer (T1)
Steps down genset power from 460-480VAC to 24 VAC
(control voltage) to energize motor starters, contactors
and relays.
A. Cooling System Settings & Adjustments:
(1) Cooling Temperature Control Module ETC2.
This module is an on/off electronic temperature control with a single-pole,
double-throw relay output and light emitting diode (LED) ON indicator.
Temperature setpoint may be manually set from -30 to 130
°
F (-34 to
54.4
°
C) and controls the minimum ambient air temperature at which the
air conditioning system is initially enabled. An adjustable temperature
differential may be varied from 0-30
°
F (or 0-17
°
C) and controls the
ambient air temperature at which the air conditioning system is disabled.
Ambient air temperature is sensed via remote temperature sensor (RTD2)
mounted near the inlet air filter. (Refer to Section 2-4, Adjustments and
Tests)
(a) Factory Settings:
•
Temperature Setpoint: 50
°
F (10
°
C)
•
Differential: 1
°
F (or .5
°
C)
