Table 9-1. Stator Winding Data (50/60 Hz)
Type of winding
No. of slots and coils
No. of coils per group
Turns per coil
3 phase, dual voltage
84 slots 84 coils
6 of AWG #15 (0. 0571 dia)
4.2 ckt, (See fig. 9-3)
0.026 ohm at 25° (T1-T4, etc.)
(a) Preheat wound core for 1 1/2 hours (2
(e) With the rotor body turning on the ma-
hours maximum) in forced convection oven maintain-
chine, guide the wire into the slots for the specified
ed at 170° C.
number of turns. Hold the wire with enough tension
on the tension blocks to assure a hard firm winding.
(b) Cool core down to a temperature of 1050
Traverse the wire at the end turns and not in the
to 115° C and dip at this temperature-into varnish,
connection end up, until all bubbling stops, or for 3
minutes, whichever is longer.
(c) Remove wound core and drain connection
end up for four minutes.
(d) Rotate wound core so connection end is
down and drain for one minute.
(e) Bake wound core with slots in horizontal
position for 2 hours in forced convection oven main-
tained at 170° C.
(f) Repeat steps b, C, d, e and f two times
so that a total of three dips and bakes are performed.
(g) The wound stator should be examined
for complete coverage, uniform coverage with no
strings or beads and with openings between extended
position of slot tubes, free of varnish, blistering or
peeling, and complete cure with tack-free surface
and good bonding strength.
(3) Rotor coil winding.
(a) Inspect winding slots for any sharp cor-
ners at edge and in slot. Clean up as necessary.
(b) Screw support studs into tapped holes
at bottom on slots. See figure 9-4.
(c) Examine the bore and determine the
direction in which it was removed. Place the leads
on the end where the shaft left the bore. This is so
the shaft can be pressed thru the bore in the direc-
tion it was removed.
The center of the rotor stack
must be located 11.48 inches from the hub end of
slot, as much as possible. This prevents excessive
build up of the wire in the slot.
(f) Place one spacer tool at the end of stack
and another in the approximate middle of the winding.
(g) Place winding clamp in position over
stud and force into position so that nut can be tight-
ened over end of stud.
(h) Connect poles and leads per connection
diagram. See figure 9-4. Use cold connectors and
insulate with tubing.
(i) Tie the end turns with glass roving.
(j) Seal all knots by momentarily pressing
with hot pliers long enough to fuse the roving.
Heat pliers in gas flame to Black Heat about
(k) Refer to table 9-2 for winding data.
(4) Rotor dip and bake.
(a) Preback wound core for one hour in
forced convection oven at 165° C.
(b) Dip hot wound core in varnish for one
minute with leads up.
(c) Remove wound core and drain for three
minutes with leads up.
(d) Rotate wound core with leads down and
drain for one minute.
(d) Insert slot liners as the poles are
Hold in place with sacrifice adhesive tape.