20
SPIN TEST
Before doing this procedure, follow the
Pressure
Relief Procedure Warning
on page 22 to reduce
the risk of a fluid injection injury , splashing in the
eyes or on the skin, injury from moving parts, or
electric shock.
Unplug the sprayer!
WARNING
For checking armature, motor winding and brush electri-
cal continuity.
Setup
Remove the drive housing. Refer to page 31.
Remove the pressure control cover . Remove the motor
shield (23). Remove the fan cover (A) and the inspection
covers (B).
Refer to Fig 20–1.
Disconnect the two leads from the motor to the bridge
(308).
Refer to Fig 20–2.
Armature Short Circuit Test
Quickly turn the motor fan by hand. If there are no shorts,
the motor will coast two or three revolutions before coming
to a complete stop. If the motor does not spin freely, the
armature is shorted and the motor must be replaced. Re-
fer to page 32.
Armature, Brushes, and Motor Wiring Open
Circuit Test (Continuity)
Connect the two black motor leads together with a test
lead. Turn the motor fan by hand at about two revolutions
per second.
If there is uneven or no turning resistance, check the fol-
lowing: broken brush springs, brush leads, motor leads;
loose brush terminal screws, motor lead terminals; worn
brushes. Repair parts as needed. Refer to page 23.
If there is still uneven or no turning resistance, replace the
motor. Refer to page 32.
B A
308
303
30
9
302
79
23
Fig 20-1
Fig 20-2
