BS EN IEC 60934:2019

What is BS EN IEC 60934 - Circuit breakers about? 

BS EN IEC 60934 is an international standard that focuses on circuit breakers for equipment. 

BS EN IEC 60934 is applicable to mechanical switching devices designed as "circuit-breakers for equipment" (CBE) for household and similar applications. CBEs according to this document are intended to provide protection to circuits within electrical equipment including its components (e. g. motors, transformers, internal wiring).  

BS EN IEC 60934 covers CBEs applicable for the protection of electrical equipment in case of undervoltage and/or overvoltage.  

BS EN IEC 60934 also covers CBEs which are suitable for isolation.  

CBEs according to this document have: 

• A rated voltage not exceeding 440 V AC (between phases) and/or DC not exceeding 250V 
• A rated current not exceeding 125 A 
• A short-circuit capacity (Icn) of at least 6 × In (AC types) and 4 × In (DC types) but not exceeding 3000A. 

Note 1: CBEs may have a conditional short-circuit current (Inc) rating in association with a specified short-circuit protective device (SCPD). A guide for coordination of a CBE associated in the same circuit with SCPD is given. 

Note 2: For CBEs having a degree of protection higher than IP20, for use in locations where hazardous environmental conditions prevail (e. g. excessive humidity, heat or cold or deposition of dust) and in hazardous locations (e. g. where explosions are liable to occur), special constructions may be required. 

Who is BS EN IEC 60934 - Circuit breakers for? 

BS EN IEC 60934 on circuit breakers for equipment is useful for: 

• Manufacturers and suppliers of circuit breakers 
• Dealers and distributors of circuit breakers 
• Designers of circuit breakers  
• Test providers for circuit breakers 

Why should you use BS EN IEC 60934 - Circuit breakers? 

BS EN IEC 60934 contains all the requirements necessary to ensure compliance with the operational characteristics required for these devices by type tests. It also contains the details relative to test requirements and methods of testing necessary to ensure reproducibility of test results. 

BS EN IEC 60934 states the characteristics of CBEs, with reference to their operation and behaviour in normal service, in case of overload, as well as in case of short-circuits up to their rated short-circuit capacity. 

BS EN IEC 60934 gives tests intended for confirming these conditions have been met and the methods to be adopted for the tests. It gives the data to be marked on the devices and the test sequences to be carried out and the number of samples to be submitted for certification purposes. The routine tests to be carried out to reveal unacceptable variations in material or manufacture, likely to affect the safety of circuit breakers. 

What’s changed since the last update? 

BS EN IEC 60934:2019 supersedes BS EN 60934:2001+A2:2013, which will be withdrawn. The main change in BS EN IEC 60934:2019 includes clarifications for type testing purposes with respect to the previous edition.