Kool Mµ® Cores

Affordable FeSiAl Material for Low Losses at Elevated Frequencies


Kool Mµ material’s low loss and relatively high saturation level (10,500 gauss) make it excellent for use in power factor correction circuits (PFC) as well as unidirectional drive applications such as Pulse Transformers and Flyback Transformers. The near zero magnetostriction makes Kool Mµ (sendust) ideal for eliminating audible frequency noise in In-Line Noise Filters and Inductors. View PFC Boost design example using Kool Mu.

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Key Characteristics

  • Composition: Al • Si • Fe
  • Shapes: Toroid, E, U, EQ, LP, EER, Block, Round Block, Cylinder
  • Sizes: 4 mm to 165 mm
  • Permeability: 14µ, 26µ, 40µ, 60µ, 75µ, 90µ, 125µ
  • Coating Color: Black 
     

Large Kool Mu Toroids

Five large sizes have been added to the Kool Mu toroids, including the massive 165 millimeter coreLarge Powder Core toroids are a cost-effective option for high current applications, such as UPS, large Power Factor Correction (PFC) chokes and inverters for renewable energy.

Kool Mu Shapes 

Kool Mu Shapes (Toroids, E, U, EQ, LP, EER, Cylinders, Blocks and Round Blocks) are available in various sizes. These shapes compare favorably with gapped ferrites, powdered iron and silicon steel cores. In addition, for very large core requirements, these large shapes can be configured and bonded for a number of custom designs.

Property Curves

View Kool Mµ Material Property Curves including Normal Magnetization curves, Core Loss Density curves, Permeability versus Temperature curves, Permeability versus DC Bias curves, and Permeability versus Frequency curves.

Kool Mµ Part Number Identification

How To Order: magnetics powder cores

Core Data AL nH/T2 (nominal) Le Path Length
mm
Ae Cross Section
mm2
Ve Volume
mm3
OD max
mm
ID min
mm
HT max
mm
14µ 19µ 26µ 40µ 60µ 75µ 90µ 125µ
140         13 16 19 26 8.06 1.30 10.5 4.20 1.27 2.16
150         17 21 25 35 9.42 2.11 19.9 4.58 1.72 3.18
180         20 25 30 42 10.6 2.85 30.3 5.29 1.85 3.18
020 6 8 10 18 24 30 36 50 13.6 4.7 64 6.99 2.28 3.43
240 6 8 11 17 26 32 39 54 13.6 4.76 64.9 7.24 2.15 3.18
270 12 16 21 33 50 62 74 103 13.6 9.2 125 7.24 2.15 5.42
410 8 11 14 22 33 41 50 70 16.5 7.25 120 7.5 3.45 5.72
030 6 8 11 17 25 31 37 52 17.9 5.99 107 8.51 3.45 3.81
280 6 8 11 17 25 32 38 53 21.8 7.52 164 10.3 4.26 3.81
290 7 10 14 22 32 41 48 66 21.8 9.45 206 10.3 4.26 4.60
040 7 10 14 21 32 40 48 66 23 9.57 220 10.8 4.57 4.60
130 6 8 11 17 26 32 38 53 26.9 9.06 244 11.9 5.84 4.60
050 6 9 12 18 27 34 40 56 31.2 10.9 340 13.5 6.98 5.52
120 8 11 15 24 35 43 52 72 41.2 19.2 791 17.3 9.52 7.12
380 10 14 19 28 43 53 64 89 41.4 23.2 960 18.1 9.01 7.12
206 7 10 14 21 32 41 49 68 50.9 22.1 1,120 21.1 12 7.12
310 9 14 19 29 43 54 65 90 56.7 31.7 1,800 23.7 13.3 8.3
350 12 16 22 34 51 62 76 105 58.8 38.8 2,280 24.4 13.7 9.66
930 18 23 32 50 75 94 113 157 63.5 65.4 4,150 27.69 14.1 12
548 14 20 28 41 61 76 91 127 81.4 65.6 5,340 33.7 19.5 11.4
585 9 12 16 25 38 47 57 79 89.5 46.6 4,150 35.18 22.5 9.78
324 13 18 24 37 56 70 84 117 89.8 67.8 6,090 36.71 21.5 11.4
395 28 39 53 81 122 153 183 254 95.1 153.7 14,617 40.13 22.08 17.0
254 19 26 35 54 81 101 121 168 98.4 107 10,600 40.77 23.3 15.4
454 25 34 47 72 108 135 161 224 102 147.5 15,100 43.83 23.4 17.26
089 20 27 37 57 86 107 128 178 116 134 15,600 47.63 27.88 16.2
438 32 43 59 90 135 169 202 281 107 199 21,300 47.63 23.3 19
725 41 56 76 117 175 219 269 366 114 262 29,700 51.31 23.9 21.6
715 17 23 32 49 73 91 109 152 127 125 15,900 51.69 30.93 14.4
520 35 48 65 100 150 188 225 313 109 217 23,500 53.0 20.6 16.1
109 18 24 33 50 75 94 112 156 143 144 20,700 58.0 34.7 14.9
195 32 44 60 92 138 172 207 287 125 229 28,600 58.0 25.6 16.2
620 44 60 82 126 189 237 284 394 144 360 51,800 62.9 31.7 25.9
070 35 48 65 100 143 187 225 312 158 314 49,700 69.4 34.7 21.4
778 47 64 88 135 205 256 306 425 177.2 492 81,500 78.9 38.3 26.8
740 48 64 88 136 204 255 306 425 184 497 91,400 75.0 44.4 35.9
866 16 22 30 45 68 85 102 142 196 176 34,500 78.9 48.2 13.9
906 20 27 37 57 85 106 128 177 196 221 43,400 78.9 48.2 17.1
102 26 35 48 74 111 139 167 232 243 358 86,900 103.0 55.75 17.9
337 37 50 68 105 158       324 678 220,000 134.0 77.19 26.8
165 42 57 78           412 987 407,000 166.5 101.0 33.15
Core Data AL nH/T2 (nominal) Le Path Length
mm
Ae Cross Section
mm2
Ve Volume
mm3
Length max
mm
Leg Length min
mm
Height max
mm
14µ 26µ 40µ 60µ 90µ
1808   26 35 48 69 40.1 22.8 914 19.6 7.9 4.93
2510   39 52 70 100 48.5 38.5 1,867 25.8 9.4 6.45
3007   33  46 71  92  65.6 60.1 3,943 30.6 14.8 7.21
3515   56 75 102 146 69.4 84 5,830 35.1 14.0 9.53
4017   56 76 105 151 98.4 128 12,595 43.5 20.8 11.0
4020   80 108 150 217 98.4 183 18,007 43.5 20.8 15.7
4022   104 140 194 281 98.4 237 23,321 43.5 20.8 20.3
4317   88 119 163 234 77.5 152 11,800 41.5 16.2 12.7
5528   116 157 219 322 123 350 43,100 55.7 27.2 21.0
5530   138 187 261 338 123 417 51,400 55.7 27.2 25.0
6527 103 162 230 300   147 540 79,400 66.4 32.1 27.4
7228   130 173 235   137 368 50,400 73.5 27.4 19.4
8020 75 103 145  190   185 389 72,000 81.2 37.5 20.2
8024   200 275 370   131.4 600 78,840 81.2 23.4 30.1
8044   91 113 170   208 389 80,900 81.2 44.0 20.2
114LE 161 235   445   215  1220 262,000 115.1 45.8 35.3
130LE   254       219 1080 237,000 134.1 32.2 55.1
160LE   180       273 778 212,000 162.5 37.5 40.9
Core Data AL nH/T2 (nominal) Le Path Length
mm
Ae Cross Section
mm2
Ve Volume
mm3
Length max
mm
Leg Length min
mm
Height max
mm
26µ 40µ 60µ 90µ
3112   92 111 179 65.6 101 6,620 31.8 10.9 12.5
4110     78   85.2 80 6,816 41.2 10.7 9.9
4111   72 95 138 85.2 101 8,605 41.2 10.9 12.5
4119   110 151 218 85.2 160 13,632 41.2 10.9 19.5
5527 67       168 172 28,896 55.5 27.1 16.7
5529 85       168 244 40,992 55.5 27.1 23.6
6527 89   165   219 270 59,130 66.6 32.2 27.4
6533 82       199 250 49,750 66.6 32.2 20.4
7236 87       219 290 63,510 73.3 34.9 21.3
8020 64       273 195 53,235 81 37.5 20.2
8038 97   179   237 354 83,898 81 37.5 23.4
Core Data AL nH/T2 (nominal) Le Path Length
mm
Ae Cross Section
mm2
Length
mm
Height
mm
Width
mm
26µ 40µ 60µ
EQ20 L050 81 120 167 29.3 60.8 20.0 5.0 14.0
EQ20 L061 67 98 138 35.8 60.8 20.0 6.1 14.0
EQ26 L070 111 164 228 42.3 119.8 26.5 7.0 19.0
EQ26 L088 95 140 195 49.5 119.8 26.5 8.8 19.0
EQ26 L101 86 127 177 54.7 119.8 26.5 10.1 19.0
EQ26 L124 74 108 151 63.9 119.8 26.5 12.4 19.0
EQ32 L101 100 148 207 59.5 152.3 32.0 10.1 22.0
EQ32 L152 75 110 156 79.9 152.3 32.0 15.2 22.0
EQ32 L180 66 97 136 91.1 152.3 32.0 18.0 22.0
EQ36 L100 109 160 223 65.1 180.8 36.0 10.0 26.0
EQ36 L110 102 151 211 69.1 180.8 36.0 11.0 26.0
EQ36 L174 75 110 154 94.7 180.8 36.0 17.4 26.0
EQ41 L120 94 138 193 83.6 199.7 41.5 12.0 28.0
EQ41 L199 68 100 140 115.2 199.7 41.5 19.9 28.0
EQ50 L200 109 160 223 113.4 314.1 50.0 20.0 32.0
EQ50 L250 92 136 190 133.4 314.1 50.0 25.0 32.0
Core Data AL nH/T2 (nominal) Le Path Length
mm
Ae Cross Section
mm2
Length
mm
Height
mm
Width
mm
26µ 40µ 60µ
LP23 L087 54 79 110 49.1 67.0 23.4 8.7 14.0
LP25 L099 68 100 139 55.7 96.0 25.0 9.9 18.0
LP30 L118 65 96 134 68.0 114.0 30.0 11.8 20.0
LP32 L152 69 101 141 82.1 143.0 32.0 15.2 22.0
LP36 L144 86 127 177 80.6 177.0 36.2 14.4 24.0
LP42 L107 116 171 239 69.7 206.0 42.0 10.7 25.0
LP42 L123 106 156 218 76.1 206.0 42.0 12.3 25.0
LP42 L158 90 132 184 90.1 206.0 42.0 15.8 25.0
Core Data AL nH/T2 (nominal) Le Path Length
mm
Ae Cross Section
mm2
Ve Volume
mm3
Length
mm

Height
mm

Width
mm
26µ 40µ 60µ
ER25 L110 34 47 65 57.8 45.0 2,600 25.5 11.0 7.5
ER40 L224 59 81 111 111.3 149.1 16,600 40.0 22.4 13.3
Block
Core Data
AL nH/T2 (nominal) Ve Volume
mm3
Length
mm
Width
mm
Height
mm

Radius
mm

26µ 40µ 60µ 90µ
4741 PDF   PDF   53,600 47.5 41.0 27.5 N/A
5030   PDF  PDF  PDF    23,000  50.5 30.3 15.0 N/A
5528 PDF PDF PDF   31,200 54.9 27.6 20.6 N/A
6030 PDF     PDF 27,000 60.0 30.0 15.0 N/A
7020 PDF PDF PDF   28,600 70.5 20.3 20.0 N/A
7030  PDF       42,800 70.5 30.3 20.0 N/A
8030 PDF PDF  PDF     48,800 80.5 30.3 20.00 N/A
9541   PDF   PDF  PDF    107,200  95.0 41.0 27.5 N/A
Round Block
Core Data
                 
7543         42,504 75.0 43.0 15.5 21.5
8030         52,531 80.5 30.2 23.5 15.0
8430         53,518 84.0 30.0 23.0 15.0
9040         48,850 90.0 40.0 15.0 20.0
Part Number Permeability Width
mm
Height
mm
45µ 75µ 90µ
00K015010CXXX     X 15.0 10.5
00K015012CXXX X   X 15.0 12.0
00K015018CXXX     X 15.0 18.0
00K015022CXXX     X 15.0 22.0
00K028022CXXX   X   28.0 21.5
00K030018CXXX   X   30.0 18.0
00K030027CXXX   X   30.0 27.5
00K033022CXXX   X   33.0 21.5
00K074025CXXX     X 74.0 25.0