62-10848
2-10
2.7
Safety Devices
System components are protected from damage caused by unsafe operating conditions by automatically shutting
down the unit when such conditions occur. This is accomplished by the following fuses and safety devices.
(a) On road/standby unit only (b) This fuse is located close to the vehicle battery (12 v).
Table 2–7 Safety Devices
Unsafe Conditions
Safety Device
Automatic
restart with
fault cleared
Device Setting
Excessive drop in pressure
Automatic reset of low
pressure switch (LP)
YES
Cutout: -13.23 in HG
(- 0.45 bar)
Timer 5 min
Excessive current draw on all
microprocessor outputs (evaporator
and condenser fan)
Electronic relay
YES
Self-protected opening
Excessive current draw control circuit Fuse on electronic board
NO
Self-protected opening
Excessive current draw motor
compressor
230 = Overload relay
115/1/60 = Circuit Breaker
YES/NO
NO
Depending on Selection
See electrical wiring
diagram
Excessive current draw evaporator
and condenser fan motors
Electronic relay
YES
Self-protected opening
Excessive compressor discharge
pressure
Automatic reset of High
pressure switch (HP1)
YES
Cutout: 355 psig (24.5 bar)
Excessive current draw standby
clutch
Fuse F3 (a)
NO
Opens at 5 A (12 V)
Excessive current draw unit in
standby operation
Standby fuse F2 (a)
NO
Opens at 30 A (12 V)
Excessive current draw unit in road
operation
Fuse F1 (b)
NO
Opens at 30 A (12 V)
Connection error on primary
transformer
Fuse F4 and/or F5 (a)
NO
Opens at 4 A
Excessive temperature on standby
motor bearing
Internal Motor Thermostat
(PT0)
YES
Self-protected opening
Clutch malfunction - road (excessive
current draw)
Electronic relay
YES
Self-protected opening
Opens 311° F (155° C)
Clutch malfunction - road (insufficient
current draw)
Electronic relay
YES
Detection of min. threshold
at 750 mA
Double power supply (road + standby) Microprocessor
YES
Display on Cab Command
until one of the 2 power
supplies have been
disconnected.
Low battery voltage
Microprocessor
YES
Cutout/cut-in at 10 V
Excessive current draw on ignition
circuit (Neiman)
Fuse FI
NO
Opens at 1 A