TROUBLE SHOOTING CHART--MOTOR
NOTE: Motors used on wood-working tools
are particularly susceptible to the accumula-
tion of sawdust and wood chips and should
be blown out or "vacuumed" frequently
to prevent interference with normal motor
ventilation.
TROUBLE
Motor will not run.
Motor will not run and
fuses "BLOW."
Motor fails to develop
full power. (Power output
of motor decreases rapidly
with decrease in voltage
at motor terminals.) For
example: a reduction of
10% in voltage causes a
reduction of 19% in
maximum power output of
which the motor iscapable,
while a reduction of 20%
in voltage causes a reduc-
tion of 36% in maximum
power output.
Motor starts slowly or fails
to come up to full speed.
Motor overheats.
Starting relay in motor
will not operate.
Motor stalls resulting in
blown fusesor tripped
circuit breakers.
Frequent opening of fuses
or circuit breakers.
1.
2.
1.
2.
1.
2.
3.
4.
1.
2.
1.
2.
PROBABLE CAUSE
Protector open; circuit
broken.
Low voltage.
Short circuit in line cord or
plug.
Short circuit in motor terminal
box or loose connections.
Power line overloaded with
lights, appliances and other
motors.
Undersize wires or circuit too
long.
General overloading of power
company's facilities. (In many
sections of the country, demand
for electrical power exceeds
the capacity of existing gen-
erating and distribution
systems.)
Incorrect fuses in power line.
Low voltage--will not trip
relay.
Starting relay not operating.
Motor overloaded.
Improper cooling. (Air circula-
tion restricted through motor
due to sawdust, etc.)
1. Burned relay contacts (due to
extended hold-in periods
caused by low line voltage,
etc.)
2. Open relay coil.
3. Loose or broken connections
in motor terminal box.
1. Starting relay not operating.
2. Voltage too low to permit
motor to reach operating
speed.
3. Fuses or circuit breakers do
not have sufficient capacity.
1. Motor overloaded.
2. Fuses or circuit breakers do
not have sufficient capacity.
3. Starting relay not operating
/motor does not reach normal
speed.)
1.
2.
1.
2.
REMEDY
Reset protector by pushing in on red button, located
on top of motor junction box (indicated by audible
click).
Check power line for proper voltage.
Inspect line cord and plug for damaged insulation
and shorted wires.
Inspect all terminals in motor terminal box for loose
or shorted terminals.
1. Reduce line load.
2. Increase wire sizes, or reduce length of wiring.
3. Request a voltage check from the power company.
4. Install correct fuses.
1. Correct low voltage condition.
2. Replace relay.
1. Correct overload condition.
2. Clean out sawdust to provide normal air circulation
through motor.
1. Replace relay and check line voltage.
2. Replace relay.
3. Check and repair wiring.
1. Replace relay.
2. Correct the low line voltage condition.
3. Replace fuses or circuit breakers with proper capacity
units.
1. Reduce motor load.
2. Replace fuses or circuit breakers.
3. Replace relay.
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