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DC Compound Single Voltage Motors
DC Compound single voltage motors normally
have 2 separate field windings. 1 shunt field
which is in parallel with the armature windings
and 1 series field, which is in series with the
armature winding. For testing DC compound
motors at the motor each of the windings can be
tested separately.
The armature leads are normally labeled A1 & A2, the leads for the shunt field coil are normally
labeled F1 & F2, and the leads for the series field coil are normally labeled S1 & S2.
It is recommended to take the shunt field winding first F1 & F2 for DC1, the series field winding
second S1 & S2 for DC2 and armature winding last for DC3.
Note: Always remeasure the armature windings to look for carbon build up.
Since the Field leads are parallel to the armature windings, separate IRG to ground are taken
from the field coils to Ground or the frame and the armature coils to ground or frame a third
Insulation resistance measurement is taken from the field coil to the armature coil.
INS1 = field windings to ground
INS2 = armature windings to ground
INS3 = field winding to armature winding
STATIC readings for DC Compound Single Voltage Motors
DC1 =Series
DC2 = Shunt Field1 Coil
DC3 = Armature Coil
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