Hobart 140GT17P Operation And Maintenance Manual With Illustrated Parts List page 112

OM-2029
TROUBLE, SYMPTOM
AND CONDITION
PROTECTIVE CIRCUIT (CONTINUED)
4. Load contactor
opens during power
delivery. Under-
frequency light ON.
5. Load contactor
opens during power
delivery. Overload
indi cating
light ON.
3-1
Page 24
PROBABLE CAUSE
A. Electric governor
improperly adjusted,
or malfunctioning
(1) Governor improperly
adjusted
(2) Electric governor
system malfunc-
tioning
B. Defective over-under-
frequency sensing
module (K27)
A. There may have been
an overload condition
which caused the
overload device (K4)
to function normally.
B. One of the resistors
(R26, R27, or R28)
across overload
transformers is open
circuited.
C. Overload device
printed circuit board
Trouble Shooting Chart (Sheet 18 of 20)
Figure 4
TEST, CHECK, AND/OR
REMEDY
B. Proceed as follows:
(1) Adjust in accordance
with Sect. 2-3, Para. 3.
(2) Check and adjust or re-
pair in accordance with
ENGINE AND CONTROLS,
Troubles 8 and 9.
B. If overfrequency nuisance
tripping continues after the
governor system is proven to
be good, and an underfre-
quency condition does not
exist, replace over-under-
frequency relay, or complete
protective relay tray.
A. Observe ammeter (4, Fig. 1).
Check for abnormal overload
condition and correct. If
overload device functions to
open the load contactor when
an overload does not exist,
proceed to step B.
B. An open resistor will cause
a higher than normal volt-
age. Check resistors (Sect.
1-1; 1, Fig. 11). Replace if
defective.
C. Check voltage at terminal E,
Fig. 8. If 12-V DC, replace
September 30/89 Revised