Thread: Fuses
View Single Post
Old 15th Jul 2010, 10:13 pm   #31
Join Date: Jan 2010
Location: Coventry, Warwickshire, UK.
Posts: 339
Default Re: Fuses

Originally Posted by GMB View Post
I believe that the standard mains fuse values were carefully chosen so that the smallest one in a chain usually blows first.

It's about a factor of 3 to get this effect, hence 100A master with 30A ring and 13A on the plug and even 3A or 5A plugged into an extension.

I've seen a similar layout ,with different values though on telecomms transmission racks .The unusual thing we found was that where you'd expect the smallest to go first , at times it would be some way down the chain that one would go .This was with the manufacturers rated fuses in all places .Asked power staff to explain - they couldn't ,but had experienced it themselves .
DAVEHALL is offline