Motor Diagnostics; Control Board Diagnostics - Magnum XR Series Service Instructions Manual

Check for electrical continuity in the motor armature, windings, and brush as follows:
See Electric Shock Hazard on
page 7.
See
Pressure Relief
Procedure
Setup
1. Unplug electrical cord, and relieve pressure.
2. Remove right enclosure, and disconnect motor
harness from control board.
3. Remove fan brace.
4. Remove the four cover screws and front cover.
5. Remove yoke and guide rods, and remove gear.
Check for a damaged control board or pressure control switch as follows:
See Electric Shock Hazard on
page 7.
See
Pressure Relief
Procedure
1. Unplug electrical cord, and relieve pressure.
2. Remove the four cover screws and front cover.
3. Remove yoke and guide rods, and remove gear.
4. Remove pressure control harness from control
board. Using fingernail or tip of small, flat-
blade screwdriver, press tab on right side
connector to release.
16 309044

Motor Diagnostics

See Service Drawing on page 18.
on page 6.

Control Board Diagnostics

See Service Drawing on page 18.
on page 6.
Armature Short Circuit Test (Spin Test)
Quickly turn motor fan by hand. If there are no electri-
cal shorts, fan coasts two or three revolutions before
stopping. If fan does not spin freely, armature is
shorted. Replace motor. See Motor Kit on page 18.
Armature, Brushes, and Motor Wiring Open
Circuit Test (Continuity)
1. Connect red and black motor leads together with
test lead. Turn motor fan by hand at about two
revolutions per second.
2. If there is uneven resistance or no resistance,
replace motor. See Motor Kit on page 18.
5. Attach to the control board a harness from a
pressure switch that you know is functioning
correctly.
NOTE: Pressure control switch does not have to
be installed in pump.
6. Turn pressure control adjustment knob one turn
clockwise (increase pressure setting).
7. Plug electrical cord into 120V AC receptacle, and
turn Power switch (B) ON.
D
If motor runs, replace pressure switch.
D
If motor does not run, replace control board
and repeat test. See Control Board Kit on
page 17.