Distribution Switchgear
Covering general principles of the Switchgear function, this invaluable reference discusses topics such as interruption techniques, fault level calculations, switching transients and electrical insulation.
TABLE OF CONTENTS Distribution Switchgear
Chapter 14: Product Conformity, Quality Control and Service Problem Resolution
As it is neither practicable, nor economically feasible to type test every production circuit breaker or switch, instead, manufacturers are confined to carrying out inspections, measurements and certain limited tests, on a routine basis, to confirm that every production unit is identical to the unit that was type tested.
14.1 Serial numbers
Central to the process of the assurance of product conformity is the allocation of serial numbers. All separately tested and inspected components, such as insulators, current and voltage transformers and vacuum interrupters, should be allocated a unique serial number which should be indelibly marked on the component. This will allow data including the date of test, together with details of the tests and inspections carried out, and the names of the personnel involved to be recorded for examination at a later date if necessary.
The final assembly of the individual circuit breaker, or switch, should also be allocated a unique serial number. The in-house test and inspection records for the circuit breaker, or switch, should also list the serial numbers of all numbered subcomponents. Should a problem arise, records such as these would be essential to allow the size of a problem and the location of affected units, to be established.
While the make-up of the actual serial number is not important, so long as it is unique, a connection with the contract number or year of manufacture would be useful. Manufacturers often use one or the other of these pieces of information in their serial numbers.
14.2
Copyright The Institution of Electrical Engineers 2004 under license agreement with Books24x7
