This should include checks on the external condition of the casing of the equipment and of any cable, connectors and plugs. Cuts, fraying and other damage to cables and flexes, cracked plugs etc. are commonly found during such inspections. In addition, the interior of any 13A plug should be inspected to determined that it has been correctly wired and that it contains the correct fuse. During basic testing of equipment the effectiveness of the earth bond and the insulation are checked. These test procedures require the use of a specialist instrument.
Various models are available from electrical equipment and component stockists.
The simplest models are designed to be used by persons without expert electrical knowledge. The earth bond test ensures that any metalwork on the equipment is effectively connected to a safe earth potential and must be carried out on all exposed metalwork. This test is only applicable to earthed equipment. The insulation test ensures that any part of the equipment which the user may touch does not come into contact with any live part of the equipment. This test is applicable to all equipment.