Blown.Service.Head.Fuse

[Flakey]

Hi,
I.would.like.to.know.what.type.of.fault.would.make.a.servicehead.fuse.blow.i.would.think.a.dead.short.but.what.about.discrimination?
I.went.to.a.friends.house.as.her.sockets.were.not.working.on.a.visual.inspection.i.found.that.2.of.the.sockets.in.the.kitchen.had.connections.that.were.basically.loose.so.reconnected.them(these.sockets.were.part.of.the.ring.in.the.house.)
now.when.i.powered.up.the.board.it.blew.the.main.service.head.fuse.and.i.have.definatley.connected.the.wires.right.
i.would.have.thought.if.there.is.a.fault.on.the.ring.it.would.have.discriminated.at.the.CCU.ring.circuit.breaker.
To.be.honest.the.wiring.in.,the.house.was.absolutley.discraceful..ive.done.ir.test.which.show.circuit.is.all.good.
any.help.appreciated

PS.sorry.for.the(.....dots...).spacebar.just.broke.lol

 

[pushrod]

Fault.current.with.faulty.mcb.. Sorry couldn't resist . Yeah if there was a fault on the ring its mcb should have protected the main fuse if it was working properly.

 

[Amp David]

A big one lol

PS yer spacebar must have an intermittent fault as i'm seeing a few spaces there

 

[ezzzekiel]

old age and deterioration can cause the service fuse to pop before a mcb will trip, had it happen in the past, dno replaced the fuse and i tested the circuit and everything was fine.

maybe hes a full stop addict

 

[cjp1]

I have been to a job before where someone drilled through one leg of a ring main and the 80a main fuse had blown before the mcb had tripped .

 

[Monkey1984]

A friend of mine left his Jumper lead (for R1+R2) testing in the fuseboard and powered up and that blew the Main cut out. Was funny when he told me but he was screwing as he had to wait around for hours

 

[ezzzekiel]

done that before myself