Paul,
Quote
When you say the pole fuse didn't blow, do you mean a fuse feeding just the one house or one on a whole section of distribution?
I'm stunned that you haven't been listening all the time that I've known you. [Linked Image]
The standard NZS 3431 pole fuse pertains to a 230V wire link rated at 60A.
That actual standard these days could be referenced to wooden buildings.
Once they started fitting pole fuses with HRC fuse links to BS 88 things changed here.
A pole fuse in my language is the fuse that if removed, will disconnect that installation.
Obviously a 3 phase installation will have 3 fuses.
There is a certain error here, where these are the LV fuses in our system and yes they are on poles, but the HV fuses are known as DDO's or Dominion Drop-Outs,these are also often on the same pole but higher up feeding a step-down transformer, usually 11kV/400V.
These fuses are known in the trade as Tops.
If you go to a callout here, you will be told by the control room that either 1, 2 or 3 tops have blown.
3 Tops is a real worry, it normally means a Temporary sub-station to bypass the faulty transformer.
Never again will I try and close DDO's onto a bad transformer like that, it rained fire that night.
33,000V of angry electricity.