Hobart 60PL20 Operation And Maintenance Manual page 96

OM-2053
TROUBLE, SYMPTOM
AND CONDITION
PROTECTIVE CIRCUIT (CONTINUED)
2. Load contactor
opens during power
delivery. Under-
voltage indicating
light ON.
3. Load contactor opens
during power delivery.
Overfrequency indicating
light (DS40) ON
3-1
Page 18
PROBABLE CAUSE
A. An undervoltage con-
dition caused the
over-undervoltage
sensing module (K26)
to function normally.
B. Defective over-under-
voltage module (K26)
C. Defective protective
monitor module (K14)
A. Electric governor
improperly adjusted,
or malfunctioning
(1) Governor improp-
erly adjusted
(2) Electric governor
system malfunc-
tioning
B. Defective over-under-
frequency sensing
module (K27)
TEST, CHECK, AND/OR
REMEDY
A. Observe generator voltage on
voltmeter and adjust to normal
115 V AC with voltage
regulator potentiometer (27,
Fig. 1). Resume normal oper-
ation. If the load contactor
opens again and an under-
voltage condition is indi-
cated by UV indicating
light, proceed to step B.
B. Use potentiometer (27, Fig.
1) to reduce voltage to 104
V. The undervoltage indi-
cating light should NOT come
on during a time delay of 4
to 12 seconds. If the light
comes on before a delay of 4
to 12 seconds, the under-
voltage relay is defective.
Replace the module (K26).
C. With unit running normally,
use potentiometer (27, Fig.
1) to reduce voltage quickly
to 90 V. If the undervoltage
indicating light (DS38) is
turned ON immediately, the
protective monitor circuitry
is defective. Replace
protective monitor (K14).
A. Proceed as follows:
(1) Adjust in accordance with
Sect. 2-3, Para. 3, E, (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 overfrequency con-
dition does not exist, replace the
toverunder frequency module (K27).
December 31/91 Revised