Equipment Protection Level : Made Easy
In electrical engineering, SWITCH is a SIMPLE COMPONENT that can MAKE or BREAK an electrical circuit . (Wikipedia)
The ASCENT OF THIS simple device can give us an insight into the development of Electrical Standards in general & Hazardous Area Standards in particular.
Let us follow
The ASCENT OF A SWITCH ( writer's personal view )
The article is from Asif Mirza - https://expeltec.com/2017/04/12/equipment-protection-level-made-easy/