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Electricity > Lamps

Most schools use a few different types of bulbs or lamps in science. Most people will be familiar with the standard bayonet cap (BC) mains lamps that are use in the home (see fig 1 below).

Fig 1. Standard bayonet cap (BC) and Edison Screw (ES) mains lamps
Fig 1:
Standard bayonet cap (BC) and Edison Screw (ES) mains lamps
(refer to table below for lamp data)

These may be used in desk lamps in schools. There are also 240V mains lamps with screw fittings (see fig 1 above) (ES – standing for Edison Screw) and a number of miniature ES and BC types (see fig 2 below).

Fig 2: A selection of miniature BC and ES lamps
Fig 2: A selection of miniature BC and ES lamps
(refer to table below for lamp data)

The table below shows the main types that will be used in schools:

Name Diameter
of base
Uses Photo (see
figs 1 & 2)
Mains BC (bayonet Cap) 22mm Mains lighting 1
SBC (small bayonet cap 15mm Mains and 12V types available 2
ES (Edison Screw) 27mm Mains desk lamps 3
MES (miniature Edison Screw) 10mm Low voltage. Generally 1-12V 4
LES (Lilliput Edison Screw) 5mm Low voltage (MFA kits etc) 5
GES (giant Edison Screw) 40mm For mains lamps over 500W. Heat lamps etc 6
MCC (miniature centre contact) 10mm Low voltage, torches etc 7

Care should always be taken when using mains desk lamps or bayonet holders in lessons. Students should be made aware of the dangers of mains electricity and care should be taken to ensure the fittings cannot come into contact with water.