How do I make this safer than it is now?

[yellowvanman]

TT system wired about 10 years ago, using a 16th Edition board but with no 100mA RCD as main switch. (muppet!)

As it stands the 30mA doesn't trip and so needs changing anyway.

Whats the best way to protect the non RCD circuits without spending a fortune? The options I think I have are:

1) Change main 100A switch for a 100mA time delayed RCD - as it should have been in the 1st place

2) Change main 100A switch with a 30mA RCD - trouble is there is no discrimination with the other RCD in the board! Or don't even bother changing the other RCD and just have 1 protecting all circuits!

3) Change non RCD MCBs with RCBOs - too expensive.

Anyone got another option? I'm inclined to do No. 2.

 

[i=p/u]

option 2 seems easiest

 

[johnboy6083]

i would use option A. Then you have discrimination, and the option to add RCBO's later if the client wishes

 

[WPD Lad]

See if the DNO will give you a PME?

 

[ezzzekiel]

option 3 for me, cost shouldnt be an issue.

 

[TPES]

When I used a TT for my assessment there was no 100mA RCD as a main switch, there was a dual RCD CU with 30mA protection to every circuit.. This was perfectly acceptable

 

[telectrix]

buy a dual RCD board from B&Q £50. 10% off on wednesdays if you not over 60, take your granny with you.

 

[ezzzekiel]

When I used a TT for my assessment there was no 100mA RCD as a main switch, there was a dual RCD CU with 30mA protection to every circuit.. This was perfectly acceptable

If all circuits had 30ma protection then there would be no need for a 100ma, depending on the amount of non protected circuits then board swap as tel says sounds the better option

 

[Amp David]

What board is it by the way?

 

[telectrix]

BG, British General. 10 way, hi integrity.

 

[yellowvanman]

Legrand board.

I reckon changing MCBs to RCBOs would be cheaper than changing board but customer doesn't want to pay that sort of money. Its been like this for 9-10 years and obviously customer asks why do I need to spend money on this? I'm twisting her arm to do something at least.

Sorry I thought the question was directed at me.

 

[Amp David]

Only asking regards board make as depending on how many RCBOs you need it'll probably be cheaper than the time delayed RCD option.

Yes, sorry it was aimed at YellowVanMan.

 

[Engineer54]

If this is your typical 200 ohm UK TT system, then it's got to be all RCBO, with a 100mA RCD front end!! .... As wirepuller says it'll not be too often, you'll get two RCD devices failing on you at the same time... lol!!

 

[Knobhead]

As wirepuller says it'll not be too often, you'll get two RCD devices failing on you at the same time... lol!!

Famous last words.
I’ve just been watching a documentary about the Titanic!

 

[Geordie Spark]

Famous last words.
I’ve just been watching a documentary about the Titanic!

Damn !!!

I would have liked to watch that, but didn't know it was on.

Which channel was it on Tony?

Maybe it'll be repeated later.