INVERTERS

[Guest]

does it annoy you as it does me that people think 12v is safe because its a low voltage? its the amount of current that can discharge thats the problem, please don't try it at home but do people know a mess it can make of a spanner if it arcs across the poles? and the mess of your hand if the spanner is not insulated.

Yes, it is unfortunate that people have less fear of DC low voltage than "mains".

When I started working in GPO telephone exchanges 45 years ago, the equipment was electro-mechanical in those days rather than the computerised electronic systems of today. All of the selectors and relays worked on 50 volts DC, which you could safely touch with your bare hands, as the body's resistance was too high for the current to track through.

This made some apprentices a little to blasé and caused serious injuries. One had serious burns to his hand when he rested his metal wire cutters across the bus-bars, and they instantly melted into a lump of molten steel in a blinding flash. Although the voltage was only 50 volts DC, the current was thousands of amps from the wet cell battery system that filled the ground floor. Another apprentice lost a finger when his ring bridged the busbars whilst he was groping between them. (Despite the dire warnings and gory videos during the training).

[MBA Marine]

Yes, it is unfortunate that people have less fear of DC low voltage than "mains".

When I started working in GPO telephone exchanges 45 years ago, the equipment was electro-mechanical in those days rather than the computerised electronic systems of today. All of the selectors and relays worked on 50 volts DC, which you could safely touch with your bare hands, as the body's resistance was too high for the current to track through.

This made some apprentices a little to blasé and caused serious injuries. One had serious burns to his hand when he rested his metal wire cutters across the bus-bars, and they instantly melted into a lump of molten steel in a blinding flash. Although the voltage was only 50 volts DC, the current was thousands of amps from the wet cell battery system that filled the ground floor. Another apprentice lost a finger when his ring bridged the busbars whilst he was groping between them. (Despite the dire warnings and gory videos during the training).

nasty stories, makes me thankfull i do not wear rings or a watch