Shibaura ST318, Workshop Manual

Page: 77 / 247

76
Inspection
(1) Armature
➀
Check the insulation between the commutator and
the armature with 500 V megger. The armature is
normal if there is resistance of more than 0.1 mega
ohm.
➁
Layer insulation test (short-circuit test)
Setting the armature on the growler tester, check the
layer insulation.
If no vibration is resulted when placing an iron rod
on the armature core, the layer insulation is
favorable.
NOTE: Before inspection, remove foreign matters
between commutator and segments.
(2) Commutator
➀
Check for roughness and burning damage. If the
surface is not smooth, correct with sand paper (No.
500 or 600).
➁ Check outside diameter of the commutator.
Standard assembling value Service limit
30 mm 29 mm
➂
Depth of insulator (mica) between segments.
Standard depth Service limit
0.5 – 0.9 mm 0.2 mm
T199
T200
T201