RJ150-30 / Operations and Maintenance Manual
Mobile Aircraft Air Conditioner
Trailer Mounted, Cool Mode Only
______________________________________________________________________________
SECTION 2 - 4
JANUARY 20, 2004
PAGE 6
Table 1. Electrical Controls Box
Figure 7
Item No.
Description
Function
1
Blower Motor Starter (MS1)
Thermal Setting: 9-13A
Integral 3-pole disconnect, motor overload and circuit
breaker with trip indication providing 480VAC, 3-phase
to the blower motor contact.
Normal trip setting: 13 A
1A
Blower Motor Contactor (MC1)
Provides 3-phase power to blower motor (M1). This
24VAC contactor is energized when the OFF/GEN
ON/FAN ON selector switch is set to FAN ON and
24VAC control voltage is available.
2
Compressor #1 Motor Starter
(MS2)
Thermal Setting: 14-20A
Integral 3-pole disconnect, motor overload and circuit
breaker with trip indication providing 480VAC, 3-phase
to compressor contactor MC2.
Normal trip setting: 20 A
2A
Compressor #1 Motor
Contactor (MC2)
Provides 3-phase power to compressor motor #1 (M2).
This 24VAC contactor is energized when cool signal is
enabled at cooling temperature control module-2
(ETC2).
3
Condenser Fan Motor Starter
(MS3)
Thermal Setting: 6.3 - 10A
Integral 3-pole disconnect, motor overload and circuit
breaker with trip indication providing 480VAC, 3-phase
to condenser fan motor contactor MC3.
Normal trip setting: 10 A
3A
Condenser Fan Motor
Contactor (MC3)
Provides 3-phase power to condenser fan motor (M3).
This 24VAC contactor is energized when the unit is
turned “ON” and 24VAC control voltage is available.
4
Compressor #2 Motor Starter
(MS4)
Thermal Setting: 14-20A
Integral 3-pole disconnect, motor overload and circuit
breaker with trip indication providing 480VAC, 3-phase
to compressor contactor MC4.
Normal trip setting: 20 A
4A
Compressor #2 Motor
Contactor (MC4)
Provides 3-phase power to compressor motor #1 (M2).
This 24VAC contactor is energized through compressor
#1 contactor (MC2)
5
Power Distribution Block
(DS1)
Receives high power 480 Volt, 3-phase input, for
distribution, from the genset or optional facility power
feature.
6
Discharge Air Temperature
Control Module (ETC1)
Monitors discharge air temperature through discharge air
temperature sensor (RTD1). Provides temperature data
to temperature display module (TDM1).
7
Temperature Display Module
(TDM1)
Displays the discharge air temperature based on sensor
input from RTD1 through control module ETC1.
8
Cooling Temperature Control
Module (ETC2)
Cooling Temperature Control Module ETC2 monitors
ambient temperature (sensed by RTD2) and controls
cooling on/off setpoints. When compressor interlocks
(low/high pressure and thermal) are satisfied,
compressor operation is enabled.
Setpoint Temperature: 50° F (10° C)
Differential: 1° F (.5° C)
