First of all, I'll point out that this post is out of curiosity, its *not* revelant to anything I might do/ have done /plan to advise others to do, etc
Basically the school I am studying for my A-levels at opened in 1992, it was built on the site of an old school and the whole thing was renovated, and I think the electrics were re-done at this time, all except (apprently) the main supply into the building which was not upgraded, and is said to date from the 1960's
Recently there have been loads of computers replaced with pentium 4 machines, and quite a few air conditioners installed...you can see where this is going can't you?
Before christmas, we had a school production on, and had a few stage lights etc on at the time (not masses) when the power went off, it was traced back to one of the supply fuses, the REC was called, and after the REC person had replaced the fuse (with aid of a chisel!) the supply was restored, and we switched off the computers and the production went ahead (power went off two hours to opening!)
Fast forward to last week, there was a nasty smell in the corridor, and 45 minutes later the computer network went down, it was only after seeing the vans of both the electricians and the REC parked outside that it was obvious as to what had happened again, only this time, the power didn't come back on quickly, it was the next day before it come back, and involved the REC switching off the other two phases, and digging a big hole in the ground near where the power comes in (presumbily to splice a new piece of cable in?), apparently a lot of heat was generated.
The school is applying for funding to upgrade the supply (Apparently its only 3 x 100A at the moment), and in the short term the electricians are trying to re-balence the phases.
My question is as follows (sorry for taking a long time to get to it): Is it normal if a service fuse has a certain amount of overload on it for it to take a long time to go open circuit, and smoulder a lot in the short term, it just seems to defeat the purpose of a fuse
Basically the school I am studying for my A-levels at opened in 1992, it was built on the site of an old school and the whole thing was renovated, and I think the electrics were re-done at this time, all except (apprently) the main supply into the building which was not upgraded, and is said to date from the 1960's
Recently there have been loads of computers replaced with pentium 4 machines, and quite a few air conditioners installed...you can see where this is going can't you?
Before christmas, we had a school production on, and had a few stage lights etc on at the time (not masses) when the power went off, it was traced back to one of the supply fuses, the REC was called, and after the REC person had replaced the fuse (with aid of a chisel!) the supply was restored, and we switched off the computers and the production went ahead (power went off two hours to opening!)
Fast forward to last week, there was a nasty smell in the corridor, and 45 minutes later the computer network went down, it was only after seeing the vans of both the electricians and the REC parked outside that it was obvious as to what had happened again, only this time, the power didn't come back on quickly, it was the next day before it come back, and involved the REC switching off the other two phases, and digging a big hole in the ground near where the power comes in (presumbily to splice a new piece of cable in?), apparently a lot of heat was generated.
The school is applying for funding to upgrade the supply (Apparently its only 3 x 100A at the moment), and in the short term the electricians are trying to re-balence the phases.
My question is as follows (sorry for taking a long time to get to it): Is it normal if a service fuse has a certain amount of overload on it for it to take a long time to go open circuit, and smoulder a lot in the short term, it just seems to defeat the purpose of a fuse
but knowing the area and the local rec it probrably is.
