RDB85

~
Trainee
Nov 23, 2017
1,088
178
638
Liverpool
If you're a qualified, trainee, or retired electrician - Which country is it that your work will be / is / was aimed at?
United Kingdom
What type of forum member are you?
Trainee Electrician
I’m looking to get my consumer unit upgraded in my Garage as it’s an old Chint board that is not very good..

My Dad is looking at EV Chargers too and I was wondering if it’s possible to get a consumer unit that would handle that. The current board has MCBs for

6A - Lighting
16A Electric Fire
32A for Sockets

I’m also in the process of renewing a cable that was cut by the builders to feed my Shed which has a single socket an LED Baton light and FCU. So it’s needs an MCB for that too.
 
What is the board fed from? (MCB rating, cable size and type etc.). And what earthing system?
 
What is the board fed from? (MCB rating, cable size and type etc.). And what earthing system?

The board is fed from the main CCU in the house. It’s on a 40a mcb with a 10mm T&E it was the only cable that I available. The earthing system is a TNC-S
 
The board is fed from the main CCU in the house. It’s on a 40a mcb with a 10mm T&E it was the only cable that I available. The earthing system is a TNC-S
Two more questions:
Which installation method from table 4D5 would you say the current 10 sq mm T+E is?
Is the 10 sq mm T+E installed in such as way as to not require RCD protection?

It would be preferable to split the meter tails and use a fused switch at the house so as to be sure the MCB's at the garage can trip under fault conditions without the upstream B40 tripping. At the moment either or both could trip.

Subject to your answers being "clipped direct" and "yes" respectively there's at least three ways I can see of proceeding:
-the easy but dodgy way, change to a B50 in the house so the design current of the circuit is well in excess of the max demand when the EVCP is in use. Dodgy because you still don't have selectivity.
-the cunning way, leave the distribution circuit alone and use an EVCP system with a 2nd CT clamp to throttle charging if the garage demand exceeds 40A. For example if the electric fire is on and there's a heavy load on the RFC the EVCP could be set to throttle itself to keep the total garage demand under 40A
-the right way, change to a fused supply

You'll also need to check for a looped supply at the house and find out the supplier fuse size. Most of the time there will need to be a CT clamp at the origin to throttle charging to a grid limit of 60A. Some systems have wireless CT options. e.g. Zappi

For the board change I'd suggest Fusebox with double pole compact RCBOs.
 
  • Like
Reactions: Baddegg and DPG
Two more questions:
Which installation method from table 4D5 would you say the current 10 sq mm T+E is?
Is the 10 sq mm T+E installed in such as way as to not require RCD protection?

It would be preferable to split the meter tails and use a fused switch at the house so as to be sure the MCB's at the garage can trip under fault conditions without the upstream B40 tripping. At the moment either or both could trip.

Subject to your answers being "clipped direct" and "yes" respectively there's at least three ways I can see of proceeding:
-the easy but dodgy way, change to a B50 in the house so the design current of the circuit is well in excess of the max demand when the EVCP is in use. Dodgy because you still don't have selectivity.
-the cunning way, leave the distribution circuit alone and use an EVCP system with a 2nd CT clamp to throttle charging if the garage demand exceeds 40A. For example if the electric fire is on and there's a heavy load on the RFC the EVCP could be set to throttle itself to keep the total garage demand under 40A
-the right way, change to a fused supply

You'll also need to check for a looped supply at the house and find out the supplier fuse size. Most of the time there will need to be a CT clamp at the origin to throttle charging to a grid limit of 60A. Some systems have wireless CT options. e.g. Zappi

For the board change I'd suggest Fusebox with double pole compact RCBOs.
if this would be on a farm. it'd be a2.5mm cable protected by a 6" nail . worked for 40 years, why spend?
 
  • Like
Reactions: loz2754
Where would the best place to get a Fuse Box CCU from. I’ve counted the circuits currently in the Garage CCU:

  1. 63A Main Switch
  2. 32A Sockets
  3. 16A Electrical Heater
  4. 16A spare
I’ve got to run a circuit that will power my sheds that just have a 10w LED baton light and a Socket and FCU. That is is currently fed into a 32a mccb in a weatherproof enclosure in 4mm NYY. I’m planning on using 4mm NYY from the Garage to the MCCB.
 
Try Denmans for Fusebox bits and pieces..
 

Similar threads

OFFICIAL SPONSORS

Electrical Goods - Electrical Tools - Brand Names Electrician Courses Green Electrical Goods PCB Way Electric Underfloor Heating Electrician Courses Heating 2 Go Electrician Workwear Supplier
These Official Forum Sponsors May Provide Discounts to Regular Forum Members - If you would like to sponsor us then CLICK HERE and post a thread with who you are, and we'll send you some stats etc

Advert

Daily, weekly or monthly email

Thread starter

RDB85

Trainee
~
Joined
Location
Liverpool
If you're a qualified, trainee, or retired electrician - Which country is it that your work will be / is / was aimed at?
United Kingdom
What type of forum member are you?
Trainee Electrician

Thread Information

Title
Upgrade Consumer Unit in Garage with EV Charger Capability.
Prefix
N/A
Forum
UK Electrical Forum
Start date
Last reply date
Replies
8

Advert

Thread statistics

Created
RDB85,
Last reply from
a-z electrics,
Replies
8
Views
2,555

Advert