is built for industrial and commercial applications. It assumes the system is maintained and operated by skilled or instructed persons, demanding higher breaking capacities and more robust testing sequences. Critical Parameters Defined in IEC 60947-2
Addresses the testing and reliability requirements for breakers using microprocesser-based electronic trip units (ETUs) instead of traditional thermal-magnetic mechanisms.
When reviewing an IEC 60947-2 PDF datasheet or compliance certificate, you will encounter several critical technical symbols and metrics. Understanding these terms is essential for proper discrimination and cascading calculations. 1. Rated Operational Voltage ( Uecap U sub e iec 60947-2 pdf
Prevents a localized electrical fault from causing a total facility blackout.
The standard applies to a wide range of circuit breakers, including: is built for industrial and commercial applications
The devices governed by this standard are the workhorses of modern infrastructure, including:
Breakers without a deliberate short-time delay for selectivity under short-circuit conditions (typically molded case circuit breakers or MCCBs). When reviewing an IEC 60947-2 PDF datasheet or
is the ability of the breaker to break a specified short-circuit current multiple times (3 times in many cases) while still remaining operational afterward. It is expressed as a percentage of Icucap I sub c u end-sub (e.g., 50%, 75%, or 100% of Icucap I sub c u end-sub ) [5.3]. A higher Icscap I sub c s end-sub means better reliability and continuity of service. 4. Rated Operational Voltage ( Uecap U sub e
(Rated Impulse Withstand Voltage): The peak value of an impulse voltage wave that the equipment can withstand without failure. It measures the breaker's resilience against atmospheric overvoltages (like lightning strikes) or switching surges. Incap I sub n
A common point of confusion is choosing between an IEC 60947-2 breaker and an IEC 60898-1 breaker. The differences lie in the operating environment and user expertise: