Backroom_boy
Member
Insulator cleaning or lack of it seems to be a big issue on a lot of US metro systems. The Washington Metro has suffered a lot of smouldering incidents with dirty insulators being the cause.
I've not heard of a similar issue on the London underground; is this because cleaning has been more consistent in London or because the nominal voltage in london is about 120V less or some other issue?
Actually just realised it's even less as London is a 4 rail system so voltage is a max of +420v (with -210v on the return) I guess higher voltage systems will be more prone to flash over due to dirt.
I've not heard of a similar issue on the London underground; is this because cleaning has been more consistent in London or because the nominal voltage in london is about 120V less or some other issue?
...or because the nominal voltage in london is about 120V less or some other issue?
Actually just realised it's even less as London is a 4 rail system so voltage is a max of +420v (with -210v on the return) I guess higher voltage systems will be more prone to flash over due to dirt.
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