Replacing wired fuses (Wylex) with MCBs

[cottontop]

Hi all,

Quick question which I hope is straightforward. At the moment our fusebox looks like this;

As these are clearly quite old, is it a straight swap to put these in place;

Clearly I would need to replace the brackets behind that are inplace (these are included). Is it that straightforward or would I need to consult with an electrician ?

Many thanks

Richard

 

[333rocky333]

It is possible and straightforward to fit them, but is notifiable work

Be aware the bar is Live once the backsheilds are removed, and the ELECTRICIAN that fits them needs to change both the shield and the mcb.

There are other factors , concerning whether you are allowed to do it yourself , as you would be altering the circuits

 

[333rocky333]

That B16 although will fit is the old range, as opposed to the others which are the newer range

It would look better if all were same type, they are about £7 each i think

 

[industryspark]

tbh you would be best off consulting with an electrician. old circuits like this then i would be wanting to check each circuit and its compliance with regs i.e IR ok? continuity of conductors? zs measurments?

 

[cottontop]

we have an electrician coming in friday to test the electrics. I will get his opinion and if he says they are ok i'll get him to fit them...

thanks

 

[ban-all-sheds]

IR ok? continuity of conductors? zs measurments?

RCD protection for sockets which could reasonably be expected etc.?
More circuits for better segregation?
Ability to add a shower circuit?
Space for expansion?

A new CU might be the favourite option...

 

[JohnD]

...Be aware the bar is Live once the backsheilds are removed, ...

no it isn't, not if you turn off the main switch of the CU. there is no need to open the front plate of the enclosure.

it is best to only remove one plastic shield at a time, fit the new one, then remove the next. this reduces the chance that you could put one in the wrong way, and also minimises the exposure of the busbar anyway. Fix the circuit labels before you start, so you can check you do not misplace any of the MCBs.

 

[ban-all-sheds]

no it isn't, not if you turn off the main switch of the CU.

Or even better the external isolator.

IIRC those Wylex's aren't very well shielded inside.

 

[JohnD]

Quite. If, like Cottontop, you have one.

Some of the old Standards have unshielded screws on the incoming terminals of the main switch, but if you only remove one shield at a time, you would need very long and flexible fingers to reach them.

 

[Adam_151]

Its actually an RCD, so you may as well 'test' it with the button on the front while you are at it, chances are its been more than 3months since the last time.

(Actually I reckon its got more to do with 'excercising' it than testing it )

 

[cottontop]

Actuallt it tripped last night when the kettle stopped working !!!

 

[ban-all-sheds]

(Actually I reckon its got more to do with 'excercising' it than testing it )

It is - if you don't the mechanism can sieze up.

The other way of testing is the one I always seem to end up using, no matter how careful I am when adding anything, which is to create a N-E fault....

 

[Adam_151]

The other way of testing is the one I always seem to end up using, no matter how careful I am when adding anything, which is to create a N-E fault....

Drop the neutral out at the board?
Change the board to one with RCBOs on every circuit (and finally be able to not have everything go out when someone overfills the iron...)


(seriously hoping that the 17th forces down the prices of RCBOs)

 

[JohnD]

(seriously hoping that the 17th forces down the prices of RCBOs)

from what i see, the fleabay price has increased by a third over the last couple of months.

 

[333rocky333]

...Be aware the bar is Live once the backsheilds are removed, ...

no it isn't, not if you turn off the main switch of the CU. there is no need to open the front plate of the enclosure.

Thats fairly obvious i would have thought though!
Nothing to stop him removing them with the switch on though, and I was making him aware that the live bar would be exposed

Who said you need to take the front plate off