How To Order Magnetics Powder Cores

Magnetics powder cores have unique part numbers that provide important information about the characteristics of the cores. A description of part type is provided below.

Toroids

1. Grading Code

C0 = Graded into 2% inductance bands (OD <5 mm, 5% bands)
00 = Not graded

2. Material Code

55 = MPP
58 = High Flux
59 = Edge^®
74 = XFlux^® Ultra
75 = 75-Series
76 = Kool Mµ^® Hƒ
77 = Kool Mμ^®
78 = XFlux^®
79 = Kool Mμ^® MAX

3. Catalog Number

Designates size and permeability

4. Core Finish Code

Core Finish	Voltage Breakdown	Material Availability	OD Size Availability
A2	2,000 volts min*	MPP, High Flux, Edge	All
A7	2,000 volts min*	Kool Mµ, XFlux, XFlux Ultra, 75 Series, Kool Mμ MAX, Kool Mµ Hƒ	All
AY	600 volts min	All	3.56 - 16.6 mm
A9	8,000 volts min	All	>4.65 mm
W4	1,000 volts min	MPP	>4.65 mm
M4	1,000 volts min	MPP	>4.65 mm

AY finish not available for MPP 550µ
*A2 and A7 voltage breakdown min varies by size:
- 1000 V_AC with OD ≤4.65mm
- 1250 V_AC with 4.65mm < OD < 17.27mm
- 2000 V_AC with 17.27mm ≤ OD < 26.92mm
- 3000 V_AC with OD ≥26.92mm

Powder Core (Toroid) Stamping Summary

Size (O.D. mm)	6-digit Shop Order Number	2-digit Material Code	3-digit Catalog Number	2-digit Core Finish Code	Inductance Code	Inductance Example
6.35-6.86	•		•		•	123456 020 +6
7.87-12.7	•		•	•	•	123456 050A2 +6
>12.7	•	•	•	•	•	123456 55120A2 +6

Inductance Code is only stamped on MPP toroids with C0- Grading Code.
Shop Order number identifies the product batch, ensuring traceability of every core through the entire manufacturing process, back to raw materials.
Cores with O.D. less than 6.35 mm are not stamped.

Powder Core Toroid Stamping Examples

EQ Shape

1. Shape Code

EQ = EQ geometry

2. Material Code

G = Edge^®
H = High Flux
K = Kool Mµ^®
X = XFlux^®
Y = Kool Mµ^® MAX

3. Size Code - Back Wall

Back wall length in mm

4. Size Code - Width

Width in mm

5. Permeability Code

E026 for 26µ
E040 for 40µ
E060 for 60µ

6. Size Code - Leg

Leg length in mm

LP Shape

1. Shape Code

LP = LP geometry

2. Material Code

G = Edge^®
H = High Flux
K = Kool Mµ^®
X = XFlux^®
Y = Kool Mµ^® MAX

3. Size Code - Back Wall

Back wall length in mm

4. Size Code - Width

Width in mm

5. Permeability Code

E026 for 26µ
E040 for 40µ
E060 for 60µ

6. Size Code - Leg

Leg length in mm

EER Shape

1. Shape Code

ER = EER geometry

2. Material Code

H = High Flux
K = Kool Mµ^®
X = XFlux^®

3. Size Code - Back Wall

Back wall length in mm

4. Size Code - Width

Width in mm

5. Permeability Code

E026 for 26µ
E040 for 40µ
E060 for 60µ

6. Size Code - Leg

Leg length in mm

Non-Toroidal Shapes and THINZ

1. Grading Code

00 = Not graded

2. Material Code

F = Kool Mµ^® Hf
G = Edge^®
H = High Flux
K = Kool Mµ^®
M = MPP
X = XFlux^®
Y or A= Kool Mµ^® MAX

3. Size Code

First two digits = length in mm
Last two digits = height in mm *not listed for Large E Cores

3. Shape Code

E = E Core
T = Toroid (THINZ)
U = U core
P = I Core/Plate
B = Blocks
LE = Large E Core

4. Permeability Code

014 for 14µ
026 for 26µ
040 for 40µ
060 for 60µ
075 for 75µ
090 for 90µ

Non-Toroidal Shapes Stamping Example EQ Shape Stamping Example

Cylinders

1. Grading Code

00 = Not graded

2. Material Code

G = Edge^®
H = High Flux
K = Kool Mµ^®
X = XFlux^®

3. Size Code: OD in integer mm

4. Size Code: HT in integer mm

3. Shape Code

C = Cylinder

4. Permeability Code

014 for 14µ
026 for 26µ
040 for 40µ
060 for 60µ
075 for 75µ
090 for 90µ