BS 4145:1967
Current
The latest, up-to-date edition.
Specification for glass mica boards for electrical purposes
Hardcopy , PDF
English
31-03-1967
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Foreword
Specification
1 Scope
2 Definitions
3 Classification
4 Finish
5 Flatness
6 Thickness
7 Electric strength proof test in oil
8 Surface electric strength proof test in air
9 Insulation resistance
10 Carbon arc test
11 Spirit burner test
12 Water absorption
13 Deformation under compression
14 Shear strength
15 Cross-breaking strength
Appendices
A Conditioning of test pieces
B Electric strength proof test in oil
C Surface electric strength proof test in air
D Insulation resistance
E Carbon arc test
F Spirit burner test
G Water absorption
H Deformation under compression
J Shear strength
K Cross-breaking strength
Figures
1 Electrode arrangement for electric strength test
2 Apparatus for carbon arc test
3 Circuit diagram for carbon arc test
4 Spirit burner
5 Arrangement of test piece for spirit burner test
6 Assembly of punch, die and bolster for shear
strength test
Requirements for two types of board for electrical purposes made from glass bonded mica powder, from ⅛ in (3.2 mm) up to ½ in (12.7 mm) in thickness. Definitions, classifications, finish, flatness, thickness, electric strength proof test in oil, surface electric strength proof test in air, insulation resistance, carbon arc test, spirit burner test, water absorption, deformation under compression, shear strength and cross breaking strength. Methods of test given in appendices.
| Committee |
GEL/15
|
| DevelopmentNote |
Reviewed and confirmed by BSI, October 2012. (09/2012)
|
| DocumentType |
Standard
|
| Pages |
22
|
| PublisherName |
British Standards Institution
|
| Status |
Current
|
This British Standard specifies requirements for boards for electrical purposes, made from glass bonded mica powder, from ⅛ in (3.2 mm) up to ½ in (12.7 mm) in thickness.
NOTE Although limits are given only for boards up to ½ in (12.7 mm) thick, boards are made in greater thicknesses up to 1½ in (38.1 mm). For boards over ½ in (12.7 mm) thick, limits and test methods should be agreed between the purchaser and the supplier.
Two types of board are covered, both of which are incombustible.
The boards have good resistance to arcing, good mechanical properties and can be machined provided suitable techniques are employed. The boards are suitable for use as arc shields, terminal boards and high temperature panels.
The density of the boards covered by this standard may be taken as approximately 0.09 lb/in3 (2.5 g/cm3). Density is not, however, a guide to the quality of the board.
| Standards | Relationship |
| UNE-EN ISO 4895:2000 | Identical |
| BS 871:1981 | Specification for abrasive papers and cloths |
| BS 3718:1964 | Specification for laboratory humidity ovens (non-injection type) |
| IEC 60167:1964 | Methods of test for the determination of the insulation resistance of solid insulating materials |
| BS 3497:1979 | Specification for unimpregnated asbestos cement boards for electrical purposes |
| BS 738(1937) : LATEST | DEFINITIONS FOR NON-IGNITABLE AND SELF-EXTINGUISHING PROPERTIES OF SOLID ELECTRICAL INSULATING MATERIALS (INCLUDING CLASSIFICATION AND METHODS OF TEST) |
| BS 148:1959 | Specification for insulating oil for transformers and switchgear |
| BS 350:2004 | Conversion factors for units |
| BS 3591(1963) : AMD 2504 | |
| BS 3503(1967) : LATEST | BITUMEN IMPREGNATED ASBESTOS CEMENT BOARDS (SELF EXTINGUISHING) FOR ELECTRICAL PURPOSES |
| BS 46-3:1951 | Keys and keyways and taper pins Specification for solid and split taper pins for general engineering purposes |
| BS 2782-4.430A.D(1983) : 1983 | METHODS OF TESTING PLASTICS - CHEMICAL PROPERTIES - DETERMINATION OF WATER AND BOILING WATER ABSORPTION AT 23 DEGREES C. DETERMINATION OF WATER AND BOILING WATER WITH ALLOWANCE OF WATER-SOLUBLE MATTER |
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