EV Charger...double pole MCB?

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DaveS79

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HI all. Hope everyone well. Making some strides to start fitting EV chargers. At this stage still bit confused about some of the requirements. Am looking at installing a Hypervolt unit. This checks a lot of boxes, has in built PEN fault protection, CT monitoring so no chance of blowing main fuse and lots of settings available via App. Thing still not entirely sure of is requirements for double pole isolation. Customer looking to upgrade CU at same time so would just install dual type A rcd board.....So this covers me with the type A requirements for charger but as I understand it even if fit a type C MCB from this board for charger this is still not adequate as mcb not double pole and chargers require double pole isolation just to isolate this circuit  so the double pole RCD is not suitable? Thing is the CU is situated in enclosure very tight for space to house another mini CU. Am I missing something or over complicating this. Would just a DP isolator next to charger be suitable?

Thanks

 
Really you need to be fitting RCBo boards these days ..................

and double pole isolation - you mean like a cooker or shower isolator?

 
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When you say 'dual board' do you mean 2 RCDs so on fault you lose half the House?
That's correct yes. My job is to advise on costs and options and let customer decide. That said in 2 years of fitting mainly dual RCD boards not had anyone phoning me with any big power loss problems and if circuit schedule designed with some thought into it, it shouldn't mean major disruption if did lose half the board 

Really you need to be fitting RCBo boards these days ..................

and double pole isolation - you mean like a cooker or shower isolator?
Hi Murdoch. No one of these https://www.electricalcounter.co.uk/products/Industrial+Plugs+%26+Sockets/Rotary+Isolators%2FChangeovers/2+Pole+Isolators/BG+CPRSD240+Insulated+Rotary+Isolator+2+Pole+40A+AC+IP65+Rated/2131660629

 
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That's correct yes. My job is to advise on costs and options and let customer decide. That said in 2 years of fitting mainly dual RCD boards not had anyone phoning me with any big power loss problems and if circuit schedule designed with some thought into it, it shouldn't mean major disruption if did lose half the board 

Hi Murdoch. No one of these https://www.electricalcounter.co.uk/products/Industrial+Plugs+%26+Sockets/Rotary+Isolators%2FChangeovers/2+Pole+Isolators/BG+CPRSD240+Insulated+Rotary+Isolator+2+Pole+40A+AC+IP65+Rated/2131660629
That is fine for double pole isolation as is the use of a dual rcd consumer unit.

 
That's correct yes. My job is to advise on costs and options and let customer decide. That said in 2 years of fitting mainly dual RCD boards not had anyone phoning me with any big power loss problems and if circuit schedule designed with some thought into it, it shouldn't mean major disruption if did lose half the board 

Hi Murdoch. No one of these https://www.electricalcounter.co.uk/products/Industrial+Plugs+%26+Sockets/Rotary+Isolators%2FChangeovers/2+Pole+Isolators/BG+CPRSD240+Insulated+Rotary+Isolator+2+Pole+40A+AC+IP65+Rated/2131660629
Dual RCBO boards do NOT comply with current regs, or even 17th regs either 

 
That said in 2 years of fitting mainly dual RCD boards not had anyone phoning me with any big power loss problems and if circuit schedule designed with some thought into it, it shouldn't mean major disruption if did lose half the board 
you’ve been lucky then. I’ve come across countless homes in the last 12 or so years where a minor fault on one circuit has plunged half of the home into darkness ….

the worst are people who put all sockets on 1 rcd and all lights / cooker on the other

 
That is fine for double pole isolation as is the use of a dual rcd consumer unit.


Clearly you are offering advice outside of your depth of knowledge and/or experience..    :shakehead

I believe on multiple occasions in the past you have commented something along the lines of...

"You never do, or rarely do, or don't do much" Domestic work?

So you may not fully grasp the compliance requirements of regulation 314.1 (i)..

specifically the comment... "MINIMIZE INCONVENIENCE IN THE EVENT OF A FAULT"

its on page 50 if you need to double check...   :C

A faulty fluorescent fitting, (Neutral->Earth short), in a garage killing the power to the socket that also supplies the internet router is VERY inconvenient.....   

especially when its off and you can't reset it and the electrician can't get there till tomorrow..

As is a failing freezer compressor in the kitchen knocking off the upstairs lighting and the combi-boiler...   

Or the pond pump and water feature lights failing while you are away for a summer weekend visiting family.. 

So you come back on Sunday night to no lights or power to the fridge that has got warm!!

Plus in each of the above, the possible half a day to a full days labour paid to track down the cause of the fault can be expensive and inconvenient compared to the time & initial installation costs of a full RCBO CU..

You may well have a different opinion of the concept of "inconvenience"..

but in my experience, (trading self employed since Feb 1999),  Dual RCD board are a minefield of inconvenience!!

And anyone still installing dual RCD boards is most likely lacking an understanding of the realistic problems they can and do cause..  

Had a call yesterday from a customer I initially visited in 2015...

having problems with power tripping off..  (existing CU.. NOT installed by me.. but NOT full RCBO!)

Including loosing sockets in kitchen...

If it wasn't inconvenient they would NOT be calling me!

I am going back Friday afternoon to see what I can find...

depending upon how long I am there..

It may well have been more cost effective to have gone full RCBO initially!!

The concept of a design where a faulty circuit can remove power from a perfectly good circuit beggars belief...

about as sensible as designing a car where any single failure will illuminate ALL warning lights on the dashboard!

:C

Guinness    

 
Thats a **** way of installing an EV charge point..... always install them with their own protection (as dictated by the manufacturer)

other questions......

Have you got an EV charge point qualification?

Have you completed any manufacturer training?

do you have the specific tester and adaptor to test an EV charge point?

 
That's correct yes. My job is to advise on costs and options and let customer decide. That said in 2 years of fitting mainly dual RCD boards not had anyone phoning me with any big power loss problems and if circuit schedule designed with some thought into it, it shouldn't mean major disruption if did lose half the board 


2 years?   

In all honesty and practicality I would suggest that you have had insufficient time for you to fully comprehend the error of your ways...

re-read 314.1 (i)   then consider...

(1) would a Dual RCD board minimise inconvenience compared to a full RCBO board?

Or..

(2) would a full RCBO board minimise inconvenience compared to a Dual RCD board?

@DaveS79

If you were a close friend or relative, I would be very strongly recommending to you that Dual RCD boards are not worth the savings over full RCBO..

And if I were installing one in your house it would by full RCBO..

(I have replaced the CU's at both my Moms & Mother-In-Laws...    in both cases they now have Full RCBO boards!!!)

I wouldn't entertain messing around with a dual RCD board for anyone who is important or special to me!

:C

 
Yeh.... I think the cost puts them off.... and then the go on to install them thinking that their 5 year old MFT will test it correctly...... urm.... NO it won't
I need to buy an extra module for my MFT so if I want to install EV chargers OR test them it’s an easy upgrade for me 😀

You can hire them for a reasonable rate. I did this for the charger I installed at my place.
out of interest how much did that cost you ?

 
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