Hobart Jet-Ex 5D Operation And Maintenance Manual page 68

OM-2094 / Operation and Maintenance Manual
Jet-Ex 5D / Series 500285 / Generator Set
Generator and Controls (continued)
See section 2-4 for all figures referenced in this section.
Trouble, Symptom and Condition
7. Output current cannot be
limited by CURRENT LIMITING
CONTROL potentiometer R402
(9, Figure 4)
Chapter 2-5
Page 8
Probable Cause
a. Defective CURRENT
LIMITING CONTROL
potentiometer
b. Defective voltage regulator
VR402.
Test, Check, and Remedy
Shut down engine and check
potentiometer with an
ohmmeter. To do this,
disconnect the plug (P404) from
the regulator board (2, Figure 5)
and take resistance
measurements from pin 2 to pin
9 and then from pin 2 to pin 10
on the plug. For each
measurement, slowly turn
CURRENT LIMITING CONTROL
potentiometer through its entire
range, while observing the
ohmmeter readings. Resistance
should be from 0-10 k ohms.
Replace if necessary.
Replace voltage regulator with
one known to be good, and then
operate the generator set under
sufficient load to observe
current limiting. If CURRENT
LIMITING CONTROL
potentiometer now controls
current properly, send old
voltage regulator to factory for
service.
November 1, 2000
Revised 03/01