Changeing CCU and removing main head fuse

[justjust1]

Hi all,

I am just finishing my Level 3 City and Guilds level 3.

I am going to replace an old re-wire-able fuse type CCU with a dual RCD CCU. When replacing a CCU in the past i have just removed the main head fuse to disconnect the supply going to the CCU.

But someone at my collage has mentioned that you are supposed to contact the supplier and they will send someone out to do it? This seems a bit pointless as they will then have to re-connect after i have finished?

Can someone clarify?

Also if i can just remove the main head fuse, where would i get the wire which goes in to stop people removing the fuse? And what is it called?

Thanks

Justjust1

 

[justjust1]

It wasn't a personal dig

Yeah i know! Its good to know everyone's opinion.

 

[timo1]

Its a calculated risk, and one I feel could justify if I needed to. I definately would not do it if installation was really old and looked brittle or damaged in any way. I have bought a very yellow, very thick pair of insulated gloves for the task and make sure its gets pulled as swiftly as I can. Admittedly I look a bit daft in the gloves but I'd wear two pairs if I could!!

 

[justjust1]

Its a calculated risk, and one I feel could justify if I needed to. I definately would not do it if installation was really old and looked brittle or damaged in any way. I have bought a very yellow, very thick pair of insulated gloves for the task and make sure its gets pulled as swiftly as I can. Admittedly I look a bit daft in the gloves but I'd wear two pairs if I could!!

Exactly what i am going to do!!! Buy some good Insulated gloves that is!!!!

 

[nickblake]

MM been reading this thread with intrest , its a subject we all come across and crops up on a regular basis , here my feelings , as one post says you can cut the main fuse but not the meter seals , fine but what if the tails are damaged or very under size or dangerouse, you ring them up and they say well be there on monday they then dont turn up ,i had a 2 hour journey to a site where they didnt turn up had to go back 2 days later so was 4 hours wasted journey and fuel to , i will cut seals and re seal i do take care and wear the appropriate PPE its not that i want to break the law i just get so frustrated that i contiuousley get let down , so if i need a seal cutting i phone them up say its dangerouse and get them out on an emergency , oh thats ok if you know who the electricity supplier is if you dont your stuffed just a point heres a pic what would you do

 

[justjust1]

Walk away mate, walk away!

No in all seriousness in this situation I WOULD be calling in the service provider to diss-connect the supply and move the customer out whilst i do a full re-wire of the entire house! Judging on the state of this i recon the rest of the wiring in the house is going to be the same!

Ker Ching!!!!

 

[londonlec]

Mmmm i wonder if the energy board issue these to their staff for removing the main fuse? Or maybe every sparky has a set under their bed!

They do, I have the full set in my van.
I have, hi viz, boots, flame retardant overalls, full face mask, gauntlets, gloves (to protect gauntlets), drummond test lamp and phase finder.

 

[Electricalserv]

To pull a main fuse? We've all gone mad!

 

[nikmet]

Domestic electricity supplies can Kill you as easy as Industrial or commercial, A guy I know,s brother was killed instantly just over a year ago from a 3A supply in the garden.
99% of the time pulling dno fuses will be ok, but the one time it may go wrong you risk serious injury with difficult questions to answer afterwards.
If you call the supplier before you start the work they will come and fit a 100A DP switch after the meter, Then you can switch the old fusebox on and off as much as you like :-D

 

[justjust1]

Domestic electricity supplies can Kill you as easy as Industrial or commercial, A guy I know,s brother was killed instantly just over a year ago from a 3A supply in the garden.
99% of the time pulling dno fuses will be ok, but the one time it may go wrong you risk serious injury with difficult questions to answer afterwards.
If you call the supplier before you start the work they will come and fit a 100A DP switch after the meter, Then you can switch the old fusebox on and off as much as you like :-D

Correct me if im wrong but I thought it was the amps that kill? If so, how could he die from a 3 amp supply?

 

[cbw]

Why does an rcd operate at 30ma?

How many ma does it take to kill

???????????????????? One for you to ponder justjust1!

 

[FatBob]

50mA is the accepted figure

 

[justjust1]

Why does an rcd operate at 30ma?

How many ma does it take to kill

???????????????????? One for you to ponder justjust1!

OK so your saying that 0.3 amps can kill someone?

 

[topquark]

OK so your saying that 0.3 amps can kill someone?

No, it's milliamps!! and the recognised amount is 50 mA that's 0.050 Amps. 30mA is hopefully the cutoff before it kills someone.

 

[justjust1]

No, it's milliamps!! and the recognised amount is 50 mA that's 0.050 Amps. 30mA is hopefully the cutoff before it kills someone.

Right so its not the amps that kill then, what is it?

I suppose a mixture of environment, volts and amps!

 

[cbw]

I was hoping you would look up why RCD operates at 30ma, its STAGGERING how little amperage is needed to kill.

10ma rcds are used in some nursery applications as 30ma could kill a small child.

I love this forum, thats something new and important you have learned today!!!!



IT IS AMPS!!!!!!!!!!!!!!!