Thermo King SGCO 3000, Руководство пользователя

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Electrical Maintenance
81
Air Heater
The air heater heats the intake air to help the
engine start in cold weather. The air heater is
energized when the controller initiates a unit
start-up (unit On/Off switch in the “ON”
position).
The air heater is mounted on the open end of the
intake manifold. Check the resistance of the air
intake heater with an ohmmeter. Place the
ohmmeter leads between the M6 terminal on the
front of the heater and the screw on the back of
the heater (or the heater case). The resistance
should be 0.1 to 0.2 ohms.
Check the current draw of the heater with a
clamp-on ammeter while the engine is cranking.
Connect ammeter at the H wire near the M6
terminal on the front of the heater. The current
draw should be approximately 89 amps at 12.5
volts. The heater is probably defective if the
current draw is less than 60 amps or more than
100 amps.
Engine Low Oil Pressure
Switch
Engine oil pressure should rise immediately on
starting. This causes the oil pressure switch to
open. If the oil pressure drops below 117 ± 21 kPa
(1.17 ± 0.21 bar) (17 ± 3 psi), the switch will
close. This causes the controller to stop the
engine. A continuity tester is needed to check the
oil pressure switch. To check switch continuity
complete the following steps:
1. Remove wire OPS from the switch.
2. Continuity tester should indicate a complete
circuit between the terminal and ground.
3. Start the engine. Tester should show an open
circuit between each terminal and ground.
Repair consists of replacing the switch.
Figure 43: Engine Oil Pressure Switch
1. M6 Terminal
Figure 42: Air Heater
AXA0336