This International Standard applies to lampholders with Edison thread E14@ E27 and E40@ designed for connection to the supply of lamps and semi-luminaires* only.It also applies to switched-lampholders for use in a.c. circuits only@ where the working voltage does not exceed 250 V r.m.s.This standard also applies to lampholders with Edison thread E5 designed for connection to the supply mains of series connected lamps@ with a working voltage not exceeding 25 V@ to be used indoors@ and to lampholders with Edison thread E10 designed for connection to the supply mains of series connected lamps@ with a working voltage not exceeding 60 V@ to be used indoors or outdoors. It also applies to lampholders E10 for building-in@ for the connection of single lamps to the supply. These lampholders are not intended for retail sale.As far as it reasonably applies@ this standard also covers lampholders other than lampholders with Edison thread designed for connection of series-connected lamps to the supply.NOTE This type of lampholder is for example used in Christmas tree lighting chains.As far as it reasonably applies@ this standard also covers adapters.This standard also covers lampholders which are@ wholly or partly@ integral with a luminaire or intended to be built into appliances. It covers the requirements for the lampholder only. For all other requirements@ such as protection against electric shock in the area of the terminals or of the lamp cap@ the requirements of the relevant appliance standard shall be observed and tested after building into the appropriate equipment@ when that equipment is tested according to its own standard. Such lampholders as well as lampholders provided with a snap-on outer shell@ for use by luminaire manufacturers only@ are not for retail sale.This standard applies to lampholders to be used indoors or outdoors in residential as well as in industrial lighting installations. It also applies to candle lampholders. In locations where special conditions prevail@ as for street lighting@ on board ships@ in vehicles and in hazardous locations@ e.g. where explosions are liable to occur@ special constructions may be required.NOTE 1 This standard does not apply to three-light lampholders E26d.NOTE 2 This standard is based on the following data relative to lamps for general lighting service:?C caps E14 are used for lamps with a current not exceeding 2 A;?C caps E27 are used for lamps with a current not exceeding 4 A;?C caps E40 are used for lamps with a current not exceeding 16 A.NOTE 3 If the nominal voltage of the supply does not exceed 130 V@ the maximum current for caps E40 is 32 A (see 4.5 and 5.3).NOTE 4 Where lampholders are used in luminaires@ their maximum operating temperatures are specified in IEC 60598.