Hobart 120CU20, Руководство по эксплуатации и техническому обслуживанию с иллюстрированным списком запасных частей

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OM-2228 / Operation and Maintenance Manual
120CU20 / Series 500120 / 400 Hz. Generator Set
October 15, 2013 Chapter 2-3
Page 10
(8) Check over-frequency circuit and fault code display.
At some frequency value 420 Hz to 440 Hz, after 5 seconds, the over frequency sensing circuit
should signal the over-frequency circuit protective monitor to OPEN the load contactor and
display “
70.22 ” on fault code display.
At any frequency value exceeding 440 Hz, the over-frequency circuit should immediately signal
the protective monitor to OPEN the load contactor and display “
70.22 ” on fault code display..
To check the under frequency protective components, proceed as follows:
a While the unit is operating normally under load, set the frequency adjust switch to “ TEST ”.
Use the frequency-adjust potentiometer to adjust frequency to 400 HZ.
b Increase frequency in steps of 1 Hz, with a time delay of 5-7 seconds between steps.
c If the protective circuit opens the load contactor and displays fault “ 70.22 ” on the fault code
after 5 seconds at 426 Hz, all components of the system are functioning properly.
d If the load contactor is not opened at 426 Hz after 5 seconds, refer to Troubleshooting Chart
in Chapter 2, Section 4.
e Return unit to normal operating condition by setting the frequency adjust switch to
“
NORMAL ” and pressing “ TEST/RESET ” button switch to clear fault code.
NOTE: If the generator is operating under load at this point, open the contactors. There will be no
further need for the load bank in the following checks.
f) Testing for engine ECM faults.
(1) Set the starter enable/disable switch (Figure 7) to “ DISABLE ”. “ DISABLE ” will prevent the
engine from starting, but will still supplying 12 VDC to the control system, while checking the ECM
faults.
(2) Press the green “ ENGINE START ” push button switch. Although the engine is not running, the
green light in the “ ENGINE START ” switch will flash to indicate that power is available to the
engine ECM.
(3) If no active codes are recorded, both the “Engine Stop” and “Check Engine” (Figure 5) lamps will
come on and stay on.
If active codes are recorded, both lamps will come on momentarily, then begin to flash one code
of the recorded faults.