been adjusted for proper running speed, turn Mode Selector switch OFF.
(e)All lights on the back of the MC-900 should go off and the engine stop. If engine does not stop, check run solenoid to be sure it has returned to the stop position.
4-4.3Overspeed Switch Setting; To set the speed switch, proceed as follows:
(a)Turn Mode Selector switch to the START position.
(b)Engine should crank and start. Return switch to RUN position.
(c)With engine running, adjust governor to bring engine speed to normal RPM.
(d)Depress and hold the Overspeed Test pushbutton.
(e)Slowly turn the Overspeed Set adjustment counter- clockwise until the “Overspeed” and “Overspeed Relay” lights on the MC-900 come on and the engine shuts down.
(f)Release pushbutton; check “Overspeed” light on front panel to be sure it is on.
(g)Turn Mode Selector switch OFF to reset shutdown circuits.
(h)Restart engine, when engine starts, increase governor speed setting slowly until engine shuts down on overspeed. This should occur about 10% above governor speed.
(i)Turn Mode Selector switch OFF.
4-4.4Overcrank setting; to test the time before system shuts down on overcrank;
(a)Disconnect the run solenoid wire from terminal 6 of the Relay Module.
(b)Check time set on the “Crank Time” switch on MC-900 back panel. It is factory set at 15.
(c)Turn Mode Selector switch to START.
1.Engine will crank for 15 seconds.
2.After 15 seconds the “Overcrank” light on the MC- 900 will come on and engine will stop cranking.
(d)Turn Mode Selector switch OFF.
(e)Reconnect the run solenoid wire at terminal 6 of the Relay Module.
4-4.5Oil Pressure; to test oil pressure shutdown circuit:
(a)Turn Mode Selector switch to START. When engine starts, wait 30 seconds then,
(b)Use a jumper wire and short from terminal 28 to 4.
(c)”Oil Pressure” light will come on and engine will stop.
(d)Turn Mode Selector switch OFF.
4-4.6Water Temperature; to test the water temperature shutdown circuit:
(a)Turn Mode Selector switch to START. When engine starts, wait 30 seconds then,
(b)Use a jumper wire and short from terminal 29 to 4.
(c)“Water Temperature” light will come on and engine will stop.
(d)Turn Mode Selector switch OFF.
4-4.7All other Shutdowns; all other shutdowns would be tested in the same manner.
(a)For shutdown circuits which are locked out by the Shutdown Time Delay Bypass, you must wait 30 seconds before running the test.
(b)Circuits that are not locked out may be tested as soon as the engine is running or may be tested without starting
the engine by turning the Mode Selector switch to RUN position.
(c)To test other shutdowns, a jumper wire can be used to short the input terminal for that circuit, to ground, terminal 4.
Section 5: Operation
5-1 Operator Controls.
5-1.1Mode Selector Switch; allows the operator to start the engine (START), run the engine (RUN), or stop the engine (OFF).
5-1.2The OFF position on the mode selector also provides a reset function for the shutdown circuits. If the engine is shut down by the automatic control, the operator must turn selector off and back on to reactivate the system.
5-1.3Push to Test Lamps; this pushbutton tests the shutdown indicator lights.
5-2 Operating Modes.
5-2.1The MC-900 Generator Engine Control has only one operating mode: manual start and automatic shutdown on a sensed failure of one of the monitored inputs.
5-2.2Manual electric start is provided for operation of the generator set.
5-2.2.1To initiate Manual start, place the Mode Selector switch in the START position. This provides a start signal to the engine starter.
5-2.2.2When engine starts, return selector switch to RUN. This removes start signal and the engine will run.
5-2.3OFF or Not Operating; to prevent operation of the engine, turn selector switch OFF.
5-2.3.1The OFF position is used as a reset for any automatic shutdown that occurs.
Section 6: Routine Maintenance and Operational Tests
6-1 Routine Maintenance.
6-1.1Due to the design and types of components used, very little maintenance is required to the MC-900 Control.
6-1.2Visual inspection of the internal wiring of the control panel, along with checking wire connections for tightness, should be done on a semiannual schedule for stand- by systems or quarterly for prime power. Check wire bundles for chafing and wear to the insulation of the wires where they contact the panel or engine.
6-1.4Shutdown Circuits should be tested on a monthly basis for prime power and quarterly for stand-by sets. The same tests run during pre-operation check out, Section 4-4, should be included.
6-2 Operational Tests.
6-2.1No special operational tests are required. The routine operational tests for the generator set will exercise the control.
Section 7: Troubleshooting and Repair
7-1 Tools Required.
7-1.1Some of the tools necessary for troubleshooting are built into the MC-900 Series controls.
7-1.1.1By observing the lights on the front and rear of the control panel, clues to a problem and the possible source can be seen.
