BS EN 60947-4-3:2014

What is BS EN 60947-4-3 - AC semiconductor controllers and contactors about?  

BS EN 60947-4-3 is the fourth part of an international standard used for Low-voltage switchgear and controlgear. BS EN 60947-4-3 specifies the characteristics, requirements and types of the test method for ac semiconductor controllers and contactors. The helps in manufacturing good quality contactors and control-circuit devices used in semiconductor controllers and contactors.  

BS EN 60947-4-3 applies to a.c. semiconductor non-motor load controllers and contactors intended for performing electrical operations by changing the state of a.c. electric circuits between the ON-state and the OFF-state. Typical applications are classified by utilization categories given in Table 2. 

As controllers, they may be used to reduce the amplitude of the r.m.s. a.c. voltage on the load terminals from that of the applied voltage – either continuously or for a specified period of time. The half-wave period of the a.c. wave form remains unchanged from that of the applied voltage. They may include a series mechanical switching device and are intended to be connected to circuits, the rated voltage of which does not exceed 1 000 V a.c. This standard characterizes controllers and contactors for use with or without bypass switching devices. The semiconductor controllers and contactors dealt with in this standard are not normally intended to interrupt short-circuit currents. Therefore, suitable short-circuit protection (see 8.2.5) should form part of the installation but not necessarily of the controller itself. Contactors and control-circuit devices used in semiconductor controllers and contactors should comply with the requirements of their relevant product standard. Where mechanical switching devices are used, they should meet the requirements of their own IEC product standard and the additional requirements of this standard. 

Note: BS EN 60947-4-3 does not apply to: 

• Operation of a.c. and d.c. motors; 
• Low-voltage a.c. semiconductor motor controllers and starters covered by IEC 60947-4-2; 
• Electronic a.c. power controllers covered by the IEC 60146 series; 
• All-or-nothing solid-state relays. 

Who is BS EN 60947-4-3 - AC semiconductor controllers and contactors for? 

BS EN 60947-4-3 on Low-voltage switchgear and controlgear is useful for: 

• Semiconductor foundries 
• Manufacturer of electronic devices 
• Manufacturer of automotive parts 
• Manufacturer of circuit board  
• Electronic engineer 

Why should you use BS EN 60947-4-3 - AC semiconductor controllers and contactors?  

A Motor Starter is basically a contactor with the addition of an overload relay.  This helps in dropping out the coil voltage in case of a motor overload condition  

BS EN 60947-4-3 is useful in determining the characteristics of these ac semiconductor controllers and contactors. The constructional and performance requirement is useful in identifying the requirement and materials according to their operational activity. BS EN 60947-4-3 specifies different types of tests for controllers and contactors. This test helps in verifying the design of all forms of controllers and contactors. The EMC emission and immunity test are useful in determining and evaluating the performance of these controllers. With the help of these test method, you can ensure the sustainability of these ac semiconductor controllers and contactors in different climatic conditions.  

By applying BS EN 60947-4-3 you can manufacture good quality contactors and control-circuit devices used in semiconductor controllers and contactors.