BS 5733-2010 pdf free download

BS 5733-2010 pdf free download.General requirements for electrical accessories Specification.
for interchangeability with products conforming to other standards, the relevant dimensions shall be within the tolerances specified in the relevant standard.
For products or components which are intended to be interchangeable with products or components conforming to other standards, conformity shall be checked by inspection, measurement or gauges as specified in the relevant standards.
For products or components which are intended to be interchangeable with products or components for which there are no applicable standards, the products or components shall have dimensions and tolerances in accordance with those specified by the manufacturer or responsible vendor. Conformity shall be checked by inspection, measurement or gauges.
10 Clearances, creepage distances and solid insulation
10.1 General
Accessories energized directly from the low-voltage supply shall be Overvoltage Category Ill in accordance with Annex D.
Accessories shall be constructed so that the clearances, creepage distances and solid insulation are adequate to withstand the electrical stresses taking into account the environmental influences that may occur. Clearances, creepage distances and solid insulation shall conform to the relevant requirements of 10.2, 10.3 and 10.4.
The distance between lead wires in the pinch of a neon lamp with external resistor shall be a minimum of 1 mm.
Accessories shall conform to the requirements for basic insulation in 10.2.2 and 10.3.2 and for functional insulation in 10.2.3 and 10.3.3. If the manufacturer declares an insulation level exceeding basic insulation then the accessory shall be tested accordingly.
NOTE 1 The requirements and tests are based on 85 EN 60664-1. NOTE 2 Product insulation consists of basic insulation and protective earthing as required by 85 EN 61 740 for Class I equipment. Mechanical strength equivalent to that which would be provided by reinforced insulation as listed in 85 EN 61140 is specified for BS 5733 products through the specific mechanical and material requirements of 855733.
10.2.1 General
The clearances shall be dimensioned to withstand the rated impulse voltage declared by the manufacturer taking into account the rated voltage and the overvoltage category as given in Annex D and the pollution degree declared by the manufacturer in accordance with Annex E.
For the measurements, all parts which can be removed without the use of a tool shall be removed and moveable parts which can be assembled in different orientations shall be placed in the most unfavourable position.
NOTE Moveable parts are, for example, hexagonal nuts, the position of which cannot be controlled throughout an assembly.
10.2.2 Clearances for basic insulation
The clearances for basic insulation shall be not less than the values given in Table 1A except as described below.
It shall be permissible to use smaller unspecified clearances [except those values marked in Table 1A with a reference to Footnote B)] if the accessory passes the impulse withstand voltage test of Annex F at the impulse voltage specified in Annex D, but only if the parts are rigid or located by mouldings or if the construction is such that it is unlikely that distances will be reduced by distortion or by movement of the parts during mounting, connection and normal use.
Conformity shall be checked by inspection, and if necessary by measurement, or by the test of Annex F.
If clearance distances are to be measured, this shall be carried out in accordance with Annex B.BS 5733-2010 pdf free download.