toiroidelcores

Toroidal Standard and Custom Cores

Design Information

As always in  transformer design the user may vary the main parameters like duty cycle, frequency, induction level and the iron/copper ratio in order to reach specific objectives, or the next larger core size may be selected to accommodate a larger number of secondary windings, high voltage windings, multiple tapings or electrostatic screens. In every case the outcome will be a power rating different from the 60 Hz/15kG power capacity listed in the table. 

Going the other way, when used for autotransformers at e.g. 120V/240V step up or step down the power capacity is twice the listed VA rating.

Custom Designs

Cores with custom specified OD, ID and height are available from a fraction of an ounce to 100 lbs or more. If required, please call us at 1-800-836-5920 or send an e-mail to sales@bridgeportmagnetics.com.

Ordering Information

Our cores are available in three different configurations. You may order the cores as bare cores, epoxy fluidized or encapsulated in polycarbonate film.

The table below contains basic design information for our standard cores; approximate dimensions and the weight of completed power transformers. It also lists suggested voltage per turn, as well as the estimated voltage drop under load which is useful for calculating secondary windings.
The temperature rise listed is for complete transformers with equally loaded primaries and secondaries, operating at 100% duty cycle.

                                                    We stock the following Silicon Steel Toroidal Cores
                                                    Click on Part Number to Purchase

P/N
#

ID
 (in)

OD 
 (in)

HT 
 (in)

   BUILD  
(in)

Finished
Transformer
Weight (lbs)

Estimated VA Rating

V/TURN
@ 60Hz 15kG

%
Voltage Drop  

0

1.375

2.000

1.000

0.313

0.43

46

0.077

17.5

10

1.500

2.375

1.000

0.438

0.70

77

0.107

11.0

20

1.625

2.875

1.000

0.625

1.16

130

0.153

8.0

30

1.750

3.250

1.000

0.750

1.55

180

0.184

6.7

40

1.875

3.375

1.125

0.750

1.83

233

0.207

6.3

50

2.000

3.500

1.250

0.750

2.12

295

0.230

6.0

60

2.125

3.750

1.375

0.813

2.70

396

0.274

4.7

70

2.250

4.000

1.500

0.875

3.38

522

0.322

4.5

80

2.500

4.375

1.500

0.938

3.98

690

0.345

4.0

90

2.625

4.500

1.625

0.938

4.47

824

0.373

3.8

100

2.750

4.875

1.625

1.063

5.42

1026

0.423

3.6

110

3.000

5.250

1.750

1.125

6.69

1392

0.483

3.5

120

3.250

5.500

2.000

1.125

8.11

1867

0.551

3.5

130

3.375

5.875

2.000

1.250

9.53

2237

0.613

3.3

140

3.500

6.125

2.125

1.313

11.06

2683

0.684

3.0

150

3.625

6.375

2.500

1.375

14.16

3548

0.843

2.7

160

4.000

7.125

2.500

1.563

17.90

4909

0.957

2.5

170

4.250

7.375

3.000

1.563

22.45

6650

1.149

2.3

180

4.375

8.000

3.000

1.813

27.72

8174

1.333

2.1

190

4.750

8.625

3.000

1.938

32.03

10300

1.425

2.0

200

5.000

9.000

3.500

2.000

40.38

13744

1.716

1.8

210

5.500

10.000

3.500

2.250

50.29

18710

1.930

1.0

220

6.000

11.000

3.500

2.500

61.29

24740

2.145

1.2

L10

1.375

2.500

0.562

0.563

0.50

47

0.077

14.3

L20

1.750

3.250

0.750

0.750

1.16

135

0.138

8.3

L30

2.250

4.000

1.000

0.875

2.25

348

0.214

6.5

L40

2.750

5.250

1.125

1.250

4.64

835

0.345

4.8

L50

3.000

6.000

1.375

1.500

7.65

1458

0.506

3.1

L60

4.000

7.000

1.500

1.500

10.20

2827

0.551

3.0

L70

4.375

8.000

1.750

1.813

16.17

4768

0.777

2.6

L80

4.750

8.625

2.000

1.938

21.35

6867

0.950

2.4