Kohler 40COZ/33CFOZ Service Manual page 79

WARNING
Hazardous voltage.
Can cause severe injury or death.
Operate the generator set only when
all guards and electrical enclosures
are in place.
Hazardous voltage can cause severe injury or death.
Carefully follow instructions in the equipment manual when
testing or servicing generator set in the presence of voltage.
Grounding electrical equipment. Hazardous voltage can
cause severe injury or death. Electrocution is possible
whenever electricity is present.
breakers of all power sources before servicing the equipment.
Configure the installation to electrically ground the generator
set, transfer switch, and related equipment and electrical
circuits to comply with applicable codes and standards. Never
contact electrical leads or appliances when standing in water
or on wet ground because these conditions increase the risk of
electrocution.
SCR Assembly and Photo Transistor Board Test
1. Connect the components as
Figure 7-9. If testing the photo transistor board, the
SCR assembly must be working. If testing the SCR
assembly, the photo transistor board must be
working.
Note: When testing the SCR assembly, secure all
connections with nuts to ensure good
contact between the wire terminals and the
foil pattern.
insulated from the foil pattern and are not in
contact except when secured by a nut. Do
not exceed 1.4 Nm (12 in. lbs.) when
tightening SCR assembly nuts.
2. With the cord switch in the OFF position, plug in the
electrical cord.
3. Turn the cord switch to the ON position.
TP-5737 5/01
Moving rotor.
Open the main circuit
illustrated in
The threaded studs are
4. Shield the photo transistor board from all other light
sources during this test. Direct the test light to the
photo transistor board. If both components are
working, the test fixture light bulb lights when the
external light source is applied to the photo
transistor board. Remove the light source; the
fixture light bulb should go out. If the test fixture
light bulb does not light or is lit prior to receiving the
external light source, the tested component is
inoperative (in this example the SCR). Replace the
SCR assembly.
Note: When replacing the SCR assembly, do not
exceed a torque value of 0.9 Nm (8 in. lbs.)
when tightening the SCR mounting bolts.
1
3
4
5
2
F+ AC
F---
AC
G
9
10
11
1. SCR assembly
2. White wire
3. Red wire
4. Green wire
5. Black wire
6. Photo transistor board
7. Light source (flashlight)
8. 120-volt/100-watt lamp
9. Fuse (1 amp)
10. Switch (DPST) S1
11. 120 volts AC
Figure 7-9 SCR Assembly and Photo Transistor
Board
Section 7 Component Testing and Adjustment
7
6
8
TP-5353-7
65