Kohler 11RMY, Service Manual

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TP-5867 11/02 26 Section 4 Controller Troubleshooting
4.2.1 Starting Sequence
Placing the generator set master switch in the RUN
position closes the contact between wires N and 47,
starting the generator set locally. With the generator set
master switch in the AUTO position, closing contacts 3
and 4 starts the generator set remotely.
The start/run relay energizes, supplying power to the
relay board and control power relay K25.
The
crank/flash relay energizes and the hourmeter receives
power.
The crank/flash relay supplies field flash current to the
rotor and energizes cyclic crank relay CCR to provide
the on/off crank cycle. The CCR relay energizes starter
relay SR, which supplies power to the starter.
The K25 control power relay energizes the ignition
module, coil, governor, and gas valve.
When the engine comes up to speed, the low oil
pressure switch contacts open.
Note: The controller circuit board prevents fault
shutdowns
during startup until the crank
disconnect relay energizes.
4.2.2 Running Sequence
When generator winding 1-2 produces AC output or the
engine speed reaches 1100 rpm, the crank disconnect
relay energizes to disconnect the field flash current. The
crank/flash relay deenergizes on crank disconnect,
deenergizing the starter relay and the starter. The crank
disconnect relay energizes the fault shutdown circuit
after a 5-second delay.
Note: The generator set shuts down on overcrank fault
if the controller does not obtain AC output within
30 seconds.
4.2.3 Stopping Sequence
Place the generator master switch in the OFF/RESET
position.
The start/run relay deenergizes the relay
board and the control power relay, deenergizing engine
components. The generator set stops.
4.2.4 Fault Shutdown
Under the fault conditions listed below, the fault
shutdown relay energizes and the corresponding LED
lights. The relay’s normally open contacts close. The
normally closed relay contacts open to deenergize the
K25 relay. The K25 relay normally open contacts open
to deenergize engine components. The generator set
shuts down. To restart the generator set, first move the
generator master switch to the OFF/RESET position to
reset the controlller.
Low Oil Pressure (LOP) Shutdown
Five to eight seconds after engine lube oil pressure falls
below a safe level and the LOP switch closes, fault
shutdown occurs.
Overspeed Shutdown
When the frequency exceeds 72 Hz (or 62 Hz for 50 Hz
models), overspeed shutdown occurs.
Overcrank Shutdown
If the generator set does not start after three crank
cycles (crank/rest, crank/rest, crank), fault shutdwon
occurs.
Note: If the generator set stops from lack of fuel, the
generator set cranks in the cyclic crank
procedure for 30 seconds before shutting down
on overcrank. The generator set attempts restart
whenever speed sensor detects no rotor rotation
or AC disconnect circuit detects no AC.
4.3 Controller Circuit Board
Accidental starting.
Can cause severe injury or death.
Disconnect the battery cables before
working
on the generator set.
Remove the negative (--) lead first
when
disconnecting the battery.
Reconnect the negative (--) lead last
when reconnecting the battery.
WARNING
Disabling the generator set. Accidental starting can
cause severe injury or death. Before working on the
generator set or connected equipment, disable the generator
set as follows: (1) Move the generator set master switch to the
OFF position. (2) Disconnect the power to the battery charger.
(3) Remove the battery cables, negative (--) lead first.
Reconnect the negative (--) lead last when reconnecting the
battery. Follow these precautions to prevent starting of the
generator set by an automatic transfer switch, remote
start/stop switch, or engine start command from a remote
computer.