Subgroup
as per IEC 672

Designation

Loss factor at 20 °C
48 to 62 HZ

Permittiviy factor
48 to 62 HZ

Voltage breakdown strength, min

Specific resistance at
20 °C / 200 °C

tand_pf [10^-3]

e^r

E_d [kV mm^-1]

pv₂₀ [Wm]

C 110

Siliceous porcelain

25

6 - 7

20

10¹¹

C 120

Aluminous porcelain

25

6 - 7

20

10¹¹

C 130

Aluminous porcelain

30

6 - 7,5

20

10¹¹

C 220

Steatite

5

6

15

10¹¹

C 221

High-frequency steatite²⁾

1,5

6

20

10¹¹

C 230

Special steatite porous

*

*

*

10⁸

C 310

Titan dioxide

*

40 - 100

8

10¹⁰

C 410

Cordierite

25

5

10

10¹⁰

C 511

Porous cordierite ceramics

*

*

*

10⁷

C 520

Porous cordierite ceramics

*

*

*

10⁷

C 530

Porous cordierite ceramics

*

*

*

10⁸

C 610

Alumino silicate (50-65% AI₂O₃)

*

8

17

10¹¹

C 620

Alumino silicate (65-80% AI₂O₃)

*

8

15

10¹¹

C 780

Alumina (80-86% AI₂O₃)

1

8

10

10¹²

C 786

Alumina (86-95% AI₂O₃)

0,5

9

15

10¹²

C 795

Alumina (95-99% AI₂O₃)

0,5

9

15

10¹²

C 799

Alumina (>99% AI₂O₃)

0,2

9

17

10¹²

C 810

Beryllia

1

7

13

10¹²

C 820

Magnesia

*

10

*

*

C 910

Aluminium nitride

2

*

20

10¹²

C 930

Silicon nitride, reaction bonded

2

*

*

*

C 935

Silicon nitride, dense

2

8-12

20

10¹¹