Lincoln LT-7 Troubleshooting Manual page 26

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Troubleshooting Guide –
components. See Wiring Diagrams for troubleshooting of specific circuits.
PROBLEMS
(SYMPTOMS)
The travel motor does not run in
either the "manual" or "automatic"
position.
If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely, contact the Lincoln
Electric Service Department for electrical technical troubleshooting assistance before you proceed.Call 216-383-2531 or 1-800-
833-9353
TROUBLESHOOTING AND REPAIR
See Wiring Diagrams for location of specified
FIELD
COURSE OF ACTION
TRAVEL PROBLEMS
1. Make sure the circuit breaker is
NOT tripped.
2. Set the travel switch in "manual"
mode. Check the voltage at the
travel board #531 to #632 at the
circuit breaker. Normal is 105
to 130VAC. If the correct volt-
age is NOT present check the
circuit breaker, the R5 resistor,
the travel switch and the associ-
ated wiring. See wiring dia-
gram.
3. If the correct AC voltage IS pre-
sent at leads #531 to #632 then
check the DC voltage at the
travel direction switch (S7).
(Leads #561 to #559). Normal
is 85VDC. with the travel speed
set at maximum. If the correct
DC voltage is NOT present at
leads #561 to #559 the travel
board may be faulty. Also check
the travel speed control (R6)
and the associated wiring. See
wiring diagram
LT-7 TRACTOR
RECOMMENDED SHOP
COURSE OF ACTION
1. Check the DC armature voltage
2. If the armature voltage is NOT
3. If the correct armature voltage
CAUTION
Observe Safety Guidelines
detailed in the beginning of this manual.
being applied to the travel
motor. Leads #595 to #594.
Normal is 0 to 85VDC. depend-
ing upon the travel speed set-
ting.
(Note: In older units the travel
motor may be a shunt wound
field motor. Normal field volt-
age is 90 to 110VDC. This
may be measured at leads
#656 to #657. If field voltage is
missing check field fuse F401
on travel board).
present at leads #595 to #594
check the travel direction switch
and associated wiring. See
wiring diagram.
(and field voltage in older units)
IS present perform the Travel
Motor Test .
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