<-- Back Items 24 - 28

Item 29a. Winding Length per Turn, mlt
Use: mlt = 2 la + 2.3 t + 6.

Item 29b. Turns in Series per Phase, T/f
Use: T/f = Z / a
Should be a whole number.

Item 29c. Length per Phase Winding, L/f
Use: L/f = mlt ( T/f) / 12 feet.

Item 30. Hot Resistance per Phase, R/f
Use: R/f = ( R/f / 1000 ) × ( R_60°C / a )
Where: R_60°C = resistance per 1000 ft. at 60°C. from the wire table, Table 1.

Item 31. Voltage Drop per Phase, IR/f
Use: IR/f = Ic × R/f.

Item 32. Total Stator Copper Loss, W_{A cu}
Use: W_{A cu} = 3 Ic² ( R/f)

Item 33. Flux Density At Core, B"g_core = B"c
Convert B"g_max in Item 06 into kilogauss then relate to equivalent B"t in kilogauss using Figure 49 on page 100.
Use: B"c_trial = B"t_Fig.49 × 1000 × 6.45 / 1.366
Use: B"c_final = F / ( 2 Rd_final × ln ).
Permissible flux density in core usually between 50,000 to 85,000 lines per sq. in for 60-hz machines.

Item 34a. Net Radial Depth of Armature Core below Slots, Rd
Use: Rd_trial = F / (2 B"c_trial × ln ).
Use: Rd_final = ½ (Do_final - D - 2d ).

Item 34b. Outside Diameter of Stator, Do
Use: Do_trial = D + 2d + 2 Rd_trial.
Use: Do_final = round-off Do_trial to the nearest multiple of 1/8 inch.
Increase Rd_trial, i.e., add a multiple of 1/8 inch, if B"c_final is out of range.

Item 35. Weight of Iron in Core (Without Teeth), Wt_core
Use: Wt_core =0.28 p × (Do_final - Rd_final ) ×l_n × Rd_final.

Item 36. Weight of Iron in Teeth, Wt_teeth
Use: Wt_teeth = 0.28 × t_ave × d × ln × S_A.
Where:
t_ave = average tooth width, item 23e.
d = stator slot depth, item 28.
S_A = No. of Armature Slots, item 17.

Item 37. Losses in Core without Teeth, W_core
Use: W_core = Wt_core × f × ( watts/lb )
Where: watts/lb from Fig. 67, page 139 is based on B"g_core or B"c.

Item 38. Losses in Stator Teeth, W_teeth
Use: W_teeth = Wt_teeth × f × ( watts/lb )
Where: watts/lb from Fig. 67, page 139 is based on B"t.

Item 38. Total (Iron) Core Loss, W_{A fe}
Use: W_{A fe} = W_core + W_teeth.

Rotor Design: Items 40 - 48

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