Current Interruption Transients Calculation, 2nd Edition

8Circuit Breaker Type Testing

8.1 Introduction

To this point, we have considered current interruption transients without regard to the interaction with circuit breakers and their capability to perform the various switching duties. This capability has to be proven by type testing which covers both the mandatory type tests to be performed on all circuit breakers and the type tests related to non‐standardized applications such as shunt reactor switching.

The mandatory type tests according to IEC 62271‐100 relate to short‐circuit current interruption. This involves a number of component ratings to be proven as listed and explained in Table 8.1. As discussed in Chapter 4, the short‐circuit current interrupting capability has to be demonstrated over a range from the 100% short‐circuit current rating down to the 10% value with varying transient recovery voltage (TRV) values.

The application related current interruption type tests according to IEC 62271‐100 are listed and explained in Table 8.2. The listing includes both short‐circuit current interruption tests, for example, the short‐line fault and out‐of‐phase switching, and load current switching tests.

For the mandatory and other high‐current breaking tests, the intent is to demonstrate the circuit breaker capability to interrupt fault currents and recover against the prescribed TRVs, all within arcing window and interrupting time limits (refer to Figure 1.1). This is discussed further in the next section.

For the inductive and ...