Motor
Problem
Brake does not stop
blade within 6 sec-
onds.
Motor does not
start.
Brush sparking
when switch
released.
Wiring Diagram
Connector
Cord w/Plug
Trouble Shooting of Brake by
Qualified Service Person Only
1. Check commutation at no load. If there
is a heavy sparking which follows the
curvature of the commutator: replace
the armature.
2. To continue trouble shooting, now
unplug the power cord.
3. Install service brushes, especially if
delayed come-in of brake has been
noticed before failure.
Probable Cause
1. Brushes not seated
or lightly sticking.
2. Motor brake winding
overheated from
use of prohibited
accessory or rapid
on/off cycling.
3. Arbor screw loose.
4. Other
1. Fuse.
2. Brushes worn.
3. Other.
1. Normal automatic
brake working prop-
erly.
White Field
Lead
White
Gray Brake Lead
Black
Suggested Corrective Action
1. Inspect/clean/replace
brushes. See "Maintenance"
section.
2. Use only recommended
blades/accessories.
Let motor cool down.
3. Retighten
4. Get authorized service. See
"Troubleshooting of brake"
section.
1. Check fuse, or circuit breaker.
2. See "Maintenance" section.
3. Get authorized service.
1. None
N.C.
N.O. Switch
4. Check brake circuit for continuity:
remove brush caps and brushes. Use
ohmmeter to check continuity from
brass brush holder to brush holder. If
open, locate exact place using ohmme-
ter. As indicated by test, tighten con-
nection or replace field assembly or
replace switch.
5. After repair, check direction of blade
rotation vs. guard arrow.
33
Red Brush
Lead
Red
Armature
White Brush
Lead
Brush
Brush