Thermo King 088669, Руководство пользователя

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Electrical Maintenance (Rev. 04/03)
35
NOTE: A loss of battery voltage to either terminal EXC or
terminal SENSE will cause the alternator to stop
charging.
EXCESSIVE VOLTAGE OUTPUT
12V ALTERNATORS WITH INTERNAL
REGULAR SETTING
When a Thermo King unit is installed on a truck, it is often
connected to a truck battery. When both the Thermo King
unit and the truck engine are running on the truck battery,
the charging system with the higher voltage may automati-
cally turn off the charging system with the lower voltage
output.
If it is determined that the Thermo King regulator setting is
higher than the truck charging system or the batteries are
consuming more water than normal the following solution
may help solve the problem. Remove the wire labeled
SENSE and tape off. Add a jumper wire from 2A to the
SENSE terminal on the back of the alternator. This should
reduce the voltage to the battery by .2 to.3 of a volt.
BATTERY
Inspect and clean the battery terminals during scheduled
maintenance inspections. A dead or low battery can be the
cause of an LED or ammeter (optional) indicating discharge
due to lack of initial excitation of the alternator
NOTE: If the battery was discharged enough that a boost
was needed, the alternator may not recharge the battery
because there may not be adequate current to excite the
alternator field.
UNIT WIRING
Inspect the unit wiring and the wire harnesses during sched-
uled maintenance inspections for loose, chafed or broken
wires to protect against unit malfunctions due to open or
short circuits.
ELECTRICAL CONTACTS
Inspect all relay contacts for pitting or corrosion every
1,000 operating hours, and repair or replace as necessary.
CHARGING SYSTEM (12 VDC)
Immediately after start-up, the voltmeter may show a
discharge condition on systems with brush type alternators.
This is due to a light film build-up on the alternator slip
rings. The film build-up occurs primarily on units that have
been sitting unused for long periods of time. The film
should disappear after a minute or two, and the voltmeter
should show a high charge rate that will continue until the
battery voltage is brought back up to normal. If the
voltmeter shows a discharge after start-up, check the
alternator belt tension and all charging circuit connections
including the battery.
NOTE: On installations where the RD-II unit is connected
to the truck battery and both units are running—it is nor-
mal for the unit to indicate a discharge condition while the
truck engine is running because of the truck’s higher volt-
age charge rate.
PREHEAT BUZZER
The preheat buzzer module on the circuit board is designed
to indicate preheat is in operation.
RPM SENSOR
The rpm sensor is in the engine bell housing adjacent to, but
not touching, the flywheel (backed off 1/2 turn).
The rpm sensor is a device containing an inductance coil
and magnet. When the magnetic field is distorted by the
passing ring gear teeth, the inductance coil generates an ac