Hobart 60CU20 Operation And Maintenance Manual With Illustrated Parts List page 88

OM-2226 / Operation and Maintenance Manual
60CU20 / Series 500062 / 400 Hz. Generator Set
(5) Place the No. 1 EF bypass switch to "BYPASS / OFF" position. The No. 1 load contactor should
open at once and the yellow indicating light within the No. 1 load contactor push button switch
should go off and the fault code display should also read "EF 1", indicating a EF warning. The
corresponding LED should also indicate the EF present mode. Reset the fault by pressing the
"TEST/RESET" push button.
(6) Proceed to step 12.
(Steps 8 - 11 are only required if EF interlock system is not available on a load bank.)
(7) Connect a source of 24 V-DC power (two twelve-volt batteries connected in series) to terminals
N, F (or E) at the output terminal panel. Connection polarity is important. Connect plus (+) to
terminals E or F, and minus (-) to terminal N.
(8) Verify that when the EF Bypass switch is in the "BYPASS / ON" position or the "BYPASS / OFF"
position that the appropriate LED indication on the control panel display is correct during the
following steps 9 and 10.
(9) Place the No. 1 EF bypass switch to "BYPASS / OFF" position. Press the No. 1 contactor
operating push button switch. The No. 1 contactor power on indicating light, within the push
button switch, should glow and remain on when the push button switch is released. This indicates
that the load contactor is closed and the plug interlock circuit is functioning properly.
(10) Disconnect the 24 V-DC power source and the No. 1 load contactor should open immediately,
and the indicating light within the push button switch should go OFF. The fault code display
should also read "EF 1", indicating an EF warning. This is because the interlock circuit of the
control PC board is not receiving 28.5 VDC signal from an outside source. It indicates that the
No. 1 interlock circuit is OPEN, as it should be when the interlock circuit is not receiving a 28 VDC
signal. Reset the fault by pressing the "TEST/RESET" push button.
May 2, 2013
Figure 4: EF Bypass Indication
EF Bypass Indication
Chapter 2-3
Page 6