30
TK 61555-2-MM-EN
Figure 7.
Thermo King Alternator Terminal and Component Locations
1.
B+ Terminal (Positive Output - 2A Wire)
5.
F2 Terminal (Do Not Ground)
2.
B- Terminal (Negative Ground - CH Wire)
6.
Voltage Regulator and Brush Assembly
3.
S Terminal (Regulator Sense - 2 Wire)
7.
W Terminal (AC Output)
4.
L Terminal (Regulator Excite - 7K/EXC Wire)
Base Controller Fuse F4
The base controller has a 300 ohm resistor and a resistor bypass fuse (F4) in the alternator
excitation circuit. The fuse and resistor are connected in parallel and are located on the base
controller. Removing the resistor bypass fuse places the 300 ohm resistor in the excitation circuit
as required for Thermo King alternators (and Australian Bosch alternators). Installing the resistor
bypass fuse removes the 300 ohm resistor from the excitation circuit as required for Prestolite
alternators. See the specific unit wiring diagram for exact details.
N
No
otte
e:: The F4 fuse must be removed from the base controller on units equipped with Thermo
King alternators. The voltage regulator on the Thermo King alternators will be damaged if
the unit is turned On with the F4 fuse in place on the base controller.
Test Equipment for Checking Voltage and Current
Always use accurate test equipment such as the Fluke 23 Digital Multi-Meter and the Fluke
Clamp-On Ammeter accessory when checking alternator circuit voltage and amperage. See the
table below for Thermo King service part numbers. Verify voltages are measured from the
designated terminal to the alternator chassis ground. All voltages are DC voltages unless
otherwise noted.
Meter
Service Part Number
Fluke 23 Digital Multi-Meter
204-1079
Clamp-On Ammeter for above Meter
204-947
