Handbook of Electrical Tables and Design Criteria

Motors

Circuit Design-Data for Three-Phase Motors
60 Hz - Rigid Conduit - Copper THWN Conductors - 30 D
Calculations based on Premium Efficiency Squirrel Cage Motors

Horse Power

Runs

75 Wire

Volts L-L

Conduit Size In.

Ins. Eq. Ground Size [*]

Conduit with ENquip. Ground

Full Load Amps 100%

Design Amps 125%

Maximum Distance For 1% Drop

Approx. Percent Efficiency

Approx. Percent P.F.

Load KVA

NEC Switch Size 115%

NEMA Starter Size

Inst. C.B. HMCP Amps / 800%

Dual Ele. T.D. Fuse 175%

Inv. Time C.B. Amps 250%

1/2

1

14

480

1/2

14

1/2

1.1

1.4

998

.77

.80

0.91

30

00

3 / 9

3

5

1

14

240

1/2

14

1/2

2.2

2.8

250

.77

.80

0.91

30

00

3 / 18

6

10

1

14

208

1/2

14

1/2

2.4

3.0

198

.77

.80

0.86

30

00

3 / 19

6

10

3/4

1

14

480

1/2

14

1/2

1.6

2.0

686

.77

.80

1.32

30

00

3 / 13

3

5

1

14

240

1/2

14

1/2

3.2

4.0

172

.77

.80

1.32

30

00

7 / 26

6

10

1

14

208

1/2

14

1/2

3.5

4.4

136

.77

.80

1.25

30

00

7 / 28

10

10

1

1

14

480

1/2

14

1/2

2.1

2.6

523

.80

.80

1.74

30

00

3 / 17

6

10

1

14

240

1/2

14

1/2

4.2

5.3

131

.80

.80

1.74

30

00

7 / 34

10

15

1

14

UNLIMITED FREE
ACCESS
TO THE WORLD'S BEST IDEAS

SUBMIT
Already a GlobalSpec user? Log in.

This is embarrasing...

An error occurred while processing the form. Please try again in a few minutes.

Customize Your GlobalSpec Experience

Category: Power Plugs
Finish!
Privacy Policy

This is embarrasing...

An error occurred while processing the form. Please try again in a few minutes.