Talking about two separate supplies in one switch and commercial VS single phase
We having a talk about the building regulations guide for electricians state that there should not be two separate supplies in a switch. I get it this regulation is mostly been implemented to avoid risk from electrocution, you see where there are two separate supplies in one switch and maintenance is carried out the competent person might think that the supply is off to that switch after isolating the circuit. However a second supply present in the switch could still be live. I for one think that anyone carrying out any type of electrical work should carry out safe isolation and if they are not able to determine that the circuit they are working on is safe to touch it makes them incompetent thus they should not work on electrics. I disagree with this regulation as it is not always practical to introduce two separate switches especially in homes with such small landings. Hall stairs and landing is the most common areas for two way switching, introducing a strapper, ie three core and earth in order to have two way switching and by doing so one would probably have a two gang switch on either end, one for downstairs and one for upstairs giving the home occupier to control the lighting from either end. By following this regulation one would have to put two separate light switches two upstairs and two downstairs each opposite pair would be fed from one supply. No this is obviously a safe way of doing it but it’s not practical in most houses.