Motor Circuit Designer Page


Determine the voltage of the application and then click on the highlighted text below to find the correct table for your application.



Select here for 200 VAC or 208 VAC motors
Select here for 230 VAC or 240 VAC motors
Select here for 460 VAC or 480 VAC motors
Select here for 575 VAC or 600 VAC motors
Notes:


Data For 200 (208) VAC 3 Phase NEMA Design B, C, or D Motors.
HP FLA Wire TD Fuse TD Ckt Bkr Conduit
1/2 2.5 14 4 6 1/2
3/4 3.7 14 6 7 1/2
1 4.8 14 8 7 1/2
1.5 6.9 14 10 15 1/2
2 7.8 14 12 15 1/2
3 11 14 17.5 15 1/2
5 17.5 12 25 30 1/2
7.5 25.3 10 40 50 1/2
10 32.2 8 50 50 3/4
15 48.3 6 60 100 3/4
20 62.1 4 90 100 1
25 78.2 3 100 100 1 1/4
30 92 2 125 200 1 1/4
40 120 1/0 175 250 1 1/2
50 150 3/0 200 250 2
60 177 4/0 250 250 2
75 221 300MCM 300 400 2 1/2
100 285 500MCM 400 400 3
125 359 (2)4/0 500 600 (2)2
150 414 (2)300MCM 600 600 (2)2 1/2
200 552 (2)500MCM 800 800 (2)3






Data For 230 (240) VAC 3 Phase NEMA Design B, C, or D Motors.
HP FLA Wire TD Fuse TD Ckt Bkr Conduit
1/2 2.2 14 3 6 1/2
3/4 3.2 14 5 7 1/2
1 4.2 14 6 7 1/2
1.5 6.0 14 7.5 15 1/2
2 6.8 14 10 15 1/2
3 9.6 14 15 15 1/2
5 15.2 12 20 15 1/2
7.5 22 10 30 30 1/2
10 28 8 40 50 3/4
15 42 6 60 100 3/4
20 54 4 60 100 1
25 68 4 100 100 1
30 80 3 100 100 1 1/4
40 104 1/0 150 250 1 1/2
50 130 2/0 200 250 2
60 154 3/0 200 250 2
75 192 4/0 300 250 2 1/2
100 248 500MCM 350 400 3
125 312 500MCM 400 600 3
150 360 (2)4/0 500 600 (2)2
200 480 (2)300MCM 600 600 (2)2 1/2






Data For 460 (480) VAC 3 Phase NEMA Design B, C, or D Motors.
HP FLA Wire TD Fuse TD Ckt Bkr Conduit
1/2 1.1 14 2 2 1/2
3/4 1.6 14 2 3 1/2
1 2.1 14 3 3 1/2
1.5 3.0 14 5 6 1/2
2 3.4 14 5 7 1/2
3 4.8 14 7.5 7 1/2
5 7.6 14 12 15 1/2
7.5 11 14 15 15 1/2
10 14 12 20 30 1/2
15 21 10 30 30 1/2
20 27 10 40 50 1/2
25 34 8 50 50 3/4
30 40 8 60 50 3/4
40 52 6 80 100 3/4
50 65 4 100 100 1
60 77 3 100 150 1 1/4
75 96 1/0 150 200 1 1/2
100 124 2/0 175 250 2
125 156 3/0 200 250 2
150 180 4/0 250 250 2
200 240 300MCM 400 400 2 1/2
250 302 500MCM 400 600 3
300 361 (2)4/0 500 600 (2)2
350 414 (2)300MCM 600 600 (2)2 1/2
400 477 (2)300MCM 600 600 (2)2 1/2
450 515 (2)500MCM 800 800 (2)3
500 590 (2)500MCM 800 1200 (2)3






Data For 575 (600) VAC 3 Phase NEMA Design B, C, or D Motors.
HP FLA Wire TD Fuse TD Ckt Bkr Conduit
1/2 0.9 14 2 2 1/2
3/4 1.3 14 3 3 1/2
1 1.7 14 3 3 1/2
1.5 2.4 14 4 7 1/2
2 2.7 14 5 7 1/2
3 3.9 14 6 7 1/2
5 6.1 14 10 15 1/2
7.5 9 14 15 15 1/2
10 11 14 15 15 1/2
15 17 12 25 30 1/2
20 22 10 30 50 1/2
25 27 10 40 50 1/2
30 32 8 50 50 3/4
40 41 6 60 100 3/4
50 52 6 80 100 3/4
60 62 4 90 100 1
75 77 3 100 150 1 1/4
100 99 1/0 150 200 1 1/2
125 125 2/0 175 250 2
150 144 3/0 200 250 2
200 192 4/0 300 250 2 1/2
250 242 300MCM 400 400 2 1/2
300 289 500MCM 400 600 3
350 336 (2)3/0 500 600 (2)2
400 382 (2)4/0 600 600 (2)2
450 412 (2)300MCM 600 800 (2)2 1/2
500 472 (2)300MCM 600 800 (2)2 1/2


Notes:
#1. Motor Data based on 60Hz, NEMA Design B, C, or D, Standard Squirrel Cage Motors.
#2. Values for FLA are based on NEC Table 430-150. In actual application, please use nameplate FLA.
#3. Wire Size based on 75C wire types THW, THWN. in conduit allowing for 125% of FLA as required by NEC. Please refer to NEC for other applications
#4. Fuse size is based on NEC requirement of < 175% of FLA.
#5. Breaker size is based on NEC requirement of < 250% of FLA.
#6. Conduit size is based on maximum allowable fill amounts per NEC.
#7. Values based on NEC. It is user's sole responsibility to ensure actual motor circuit design conforms to all applicable national and local codes. These values are for educational purposes only. Due to the wide range of motor circuit applications, the author assumes no responsibility for the application of these values.

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