JLG 1230ES, Руководство по обслуживанию и ремонту

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SECTION 4 - BASE COMPONENTS
4-16 – JLG Lift – 3121222
Drive Motor Inspection and Servicing
(Reference Figure 4-5. - Drive Motor Disassembly Illustra-
tion)
1. Carefully blow out any accumulated carbon dust
and dirt from the end head and the frame and
field assembly using clean, oil free, compressed
air.
2. Replace brushes (3) that are worn below their
usable length (.600 in.), show signs of uneven
wear or signs of overheating, such as discolored
brush shunts and brush springs. Brushes should
always be replaced in complete sets of four or
eight. Use identical replacement parts; do not
substitute brush grades as the brushes are
matched to the motor type and application to
provide the best service. Substituting brushes of
the wrong grade can cause premature commu-
tator failure and excessive brush wear.
3. Make sure the brush box assembly (5) is tight on
the commutator end head. Replace brush box
assemblies in the commutator end head if they
are physically damaged or brush holders are
loose on the brush plate.
4. Visually inspect the frame and field assembly (1)
for overheating or other signs of damage. Check
all wiring to insure that the insulation is in good
condition. Verify that pole screws are torqued to
250-300 in-lb [28.2-33.9 N-m]. Verify field resis-
tance using a suitable ohmmeter per the appro-
priate motor specification. Verify that the field is
electrically isolated from the frame using a
dielectric tester. Replace as necessary.
5. Visually inspect the armature (2) assembly for
signs of overheating or physical damage. Visu-
ally inspect the seal surface of the shaft for
excessive wear. Check for grounded circuits
using a dielectric tester by applying voltage
between the commutator and the shaft. Visually
inspect the commutator for excessive wear and
overheating. Replace as necessary.
6. Visually inspect the brake surfaces for excessive
wear. Remove any RTV Silicone sealant that may
be present on the friction disc, cover, or commu-
tator end head. Replace brake assembly (11) if
necessary.
7. Visually inspect the wire harness (8) for frayed
insulation, loose terminals, or other damage.
Replace as necessary.
Figure 4-6. Drive Motor Side View Figure 4-7. Drive Motor End View (Brake End)