National Flooring Equipment 3397, Service Manual

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7
Troubleshooting Guide
Problem Cause Solution
Reduced or no
performance
Worn blast wheel or control cage Replace worn items
Belt tension Check and adjust belts
Valve does not close properly Close valve, stop motor, re-adjust valve
Too much abrasive admitted Motor must reach max. speed before opening valve
Feed motion too fast Reduce speed
Motor is rotating in the wrong direction Turn off control power; wait for motor to stop, then
turn FWD/REV switch to opposite position
Losing abrasive Bad seals Check base seals; readjust or replace
Elevation adjustment of magnets Check elevation is no higher than 5/16” (8 mm)
Magents lost field Replace magnets
Filter unit Adjust reducing damper
Dumping or
losing abrasive
Poor abrasive quality Use quality abrasives
Worn blast wheel or seals Replace blast wheel or adjust/replace seals
Control cage is not correctly adjusted Align notches to 9:00 and 11:00 position
Magnets at wrong elevation Adjust elevation of magnets
Too much dust or sand in system Check filter
Valve is opening too far and allowing too much
shot into the blast wheel, causing the Amp draw
to be over 25 Amps
Reset the valve opening so the maximum Amp draw
isn’t higher than 20 Amps on the meter
Blast valve is stuck open Inspect and remove debris
Too much dust and other
particles in storage
Insufficient air flow towards filtration unit Check rated performance of the dust collector
Check all seats
Check dust hose
Check differential pressure and replace filter ele
-
ments if pressure is too high
Motor does not start Missing phase Check power supply
Faulty switch or relays Diagnosis and replacement by electrician
Emergency stop Unlock emergency stop button
Motor stops during
operation
Current is too high Disconnect plug
Power supply circuit breaker is disengaged Reset circuit breaker or replace fuse
Motor is damaged Check motor
Inconsistent blast pattern Control cage out of adjustment Inspect and adjust control cage
Blast wheel and/or control cage are worn Replace blast wheel and/or control cage