Type test (design test) is defined as the series tests which are made upon the completion of the development of a new equipment design to establish representative performance and to demonstrate compliance with the relevant standard. Once made, these tests need not be repeated unless the design is changed so as to modify its performance. In such a case only the relevant tests need be repeated.Type testing is normally done by a testing authority independent from the equipment manufacturer. The test authority will be issuing Type test certification for the particular equipment.Switchgears and controlgears could be classified as type-test assembly (TTA) or partially type test assembly (PTTA).
A TTA is an assembly confrming to an established type or system without deviation likely to influence performance. A PTTA assembly contains both type-tested and non-type-tested arrangement provided that the later are derived from type-tested arrangement which has been compiled with relevant test.Other tests which may be performed on an electrical equipment
Tests made on each new equipment, or on parts and materials, as required, to ensure that the product meets the design specifications.Acceptance test
Tests which are made when it has been agreed between the manufacturer and the purchaser that the equipment or representative samples of an order are to be tested.
The electrical engineer should always ensure that the electrical equipment being purchase for a project are type-tested. It will reduce risks on the long term.</p