BS 5424-2 is an international standard that applies to semiconductor contactors intended for performing electrical operations by changing the state of electric circuits between on-state and off-state.
BS 5424-2 is added to IEC Publication 158-1: Low voltage controlgear, Part 1: Contactors (including Supplements A and B) which is applicable, provided it is not amended by BS 5424-2. BS 5424-2 applies only to semiconductor contactors, the main circuit of which is intended to be connected to circuits, the rated voltage of which does not exceed 1 000 V a.c. or 1 500 V d.c.
BS 5424-2 applies also to hybrid-semiconductor contactors, which are also covered by the scope of IEC Publication 158-1 as concerned to their electromagnetic part.
Note: Semiconductor contactors dealt with in BS 5424-2 are not intended to provide short-circuit protection of the main circuit but may contain short-circuit protective devices for semiconductor parts.
BS 5424-2 on semiconductor contactors specifications is useful for:
An electronic switching device called a solid-state relay (SSR) turns on or off when an external voltage (AC or DC) is applied across its control terminals. Semiconductor contactors do not have any moving parts, resulting in a longer operating lifetime. Solid-state contactors, whether for current monitoring, load management, or analogue control, have a wide range of applications, including switching motors, heaters, valves, and lighting. The load circuit can also be monitored using special solid-state contactors.
BS 5424-2 provides its users with characteristics of semiconductors contactors, states the standard conditions for construction, and guides you with test methods for routine testing for performance and efficiency.
Using BS 5424-2 guidelines ensures safety and protection, quality assurance, and high-quality products.