Classification of Transfer Switching Equipment to IEC 60947-6-1

Transfer switching equipment (TSE) is classified according to the short-circuit capability:

There are three different types of transfer switching equipment:

• Automatic Transfer Switching Equipment (ATSE)
• Manually Transfer Switching Equipment (MTSE)
• Remotely Transfer Switching Equipment (RTSE)

 
Of the ATSE type, there are three different classes of transfer switching equipment:

• Class CC: Is a TSE that is capable of making and withstanding, but is not intended for breaking short-circuit currents and is based on devices fulfilling the requirements of IEC 60947-4-1. This is usually by use of interlocked contactors.

• Class PC:  Is a TSE that is capable of making and withstanding, but is not intended for breaking short-circuit currents and is based on devices fulfilling the requirements of IEC 60947-3. This is usually by use of a motorised switching device.

• Class CB: Is a TSE that is capable of making, withstanding and is intended for breaking short-circuit currents and is provided with over-current releases and is based on devices fulfilling the requirements of IEC 60947-2. This is usually by use of motorised circuit breakers.

** Standard PC, Utility PC and Budget ATS utilise a Chinese device which conforms to GB/T 14048.11-2016. This is the Chinese version of the IEC 60947-6-1. It is not fully compatible to the latest IEC standard but a modified version labelled IEC 60947-6-1:2013, MOD