Operational Tests - Hobart Jet-Ex 5D Operation And Maintenance Manual

OM-2094 / Operation and Maintenance Manual
Jet-Ex 5D / Series 500285 / Generator Set
b. Operational Tests (Figure 1)
(1) Start the engine as described in 1-3; Para. 2, and let it warm at idle speed.
(2) Inspect for oil, fuel, and coolant leaks.
(3) Check the engine VOLTMETER (19) for proper voltage. Check OIL PRESSURE gauge (17). It
should read 35 to 60 psi (241 to 414 kPa). Check WATER TEMPERATURE gauge (15). It
should read 180 to 200º F (82 to 93º C.) when engine is hot.
(4) Observe engine RPM on the TACHOMETER (1), idle speed should be 1000 RPM ± 50 RPM.
(5) Place the SPEED CONTROL switch (10) in the RATED RPM position. Check engine RPM's at
operating speed: 2500 RPM ±50
(6) Check for 28.5 output voltage on generator VOLTMETER (3) to assure automatic voltage
buildup.
(7) Set CURRENT LIMITING CONTROL potentiometer (9) to maximum, full clockwise, position.
(8) Adjust the load bank for a load of 550 amperes.
(9) Place the CONTACTOR CONTROL toggle switch (7) in the CLOSE position. The CONTACTOR
CLOSED lamp (8) will glow as the contactor will close. Release the CONTACTOR CONTROL
toggle switch to the center ON position. The TACHOMETER (1) will indicate 2200 ± 25 RPM.
(10) Disconnect the load bank and check the overvoltage protection by adjusting voltage regulator
potentiometer R46 (1, Fig. 2) to increase the voltage. The overvoltage relay will trip and open the
load contactor between 32 to 34 volts.
(11) Readjust the voltage to 28.5 volts, connect the load bank, set it at 550 amperes, and close the
contactor.
(12) Remove load bank and check voltage regulation at no load. Voltage will be 28.5 volts.
Reconnect load bank and check voltage regulation with load bank set at 137, 275, 413, 550, and
660 amperes and check voltage at each setting. Voltage will be 28.5 ± 1 volts at each different
load.
(13) With CURRENT LIMITING CONTROL potentiometer (9) set to 2000, apply 600 to 700 amperes
load to the generator and then set the CURRENT LIMITING CONTROL potentiometer to 400.
Current displayed on AMMETER (4) will be 400 ± 40 amperes.
NOTE: Voltage will not drop below 14 volts.
(14) Set CURRENT LIMITING CONTROL potentiometer (9) to 2000 and apply 1200 amperes load.
Then set the CURRENT LIMITING CONTROL potentiometer to1000. Current displayed on
AMMETER (4) will then be 1000 ± 100 amperes and voltage will not drop
(15) Remove load. Set engine to idle. Run for 3 minuets at idle
(16) Stop and restart the engine, check the instruments as directed in step (3), and check the entire
generator set for unusual vibration and noises.
November 1, 2000
Revised 07/01
Chapter 2-3
Page 3