Second consumer unit

[Amun]

Hi,
All of the charger installations that I've seen have come off of the main consumer unit. My consumer unit doesn't have any spare capacity, but I could always have a larger one fitted. This could also have the benefit of updating my MCBs to the later safer version (RCBO?). Alternatively, I could simply get a second junction installed to take the car charger.

However, the car charger still wouldn't be in the best place for me - I'd rather have it on the detached garage. Would it be feasible to run suitable rated armoured cable (e.g. 32-40amp) as a separate feed to the garage and attach it to it's own consumer unit - which the car charger could then connect to? The current feed to the garage is only about 20amps, so I'd rather just leave that alone. Or is there a reason that it has to run from the main consumer unit?

TIA

 

[Davemac278]

I've just had an OHME smart charger fitted. It was a non standard installation as I didn't have the space on my old fuse board. Had to have a consumer box fitted just for charger. Cable run was long 15m out wall by fuse box, down side of house and round the front of house.

I had smart meters and 25mm tails installed by Lowri Beck via Avro Energy my supplier on Monday.

UK Power Networks as DPO upgraded my 60amp fuse to an 80amp fuse on Tuesday. (They will come back and fit a 100amp fuse if I upgrade my 16mm tails to 25mm to consumer unit)

I would think they could do a similar length run into your garage

 

[Amun]

Thanks for that....
We have a 100A fuse fitted already and adding another unit/switch like yours would certainly work. It's the routing that's different - e.g. something similar to your setup could work (i.e. running the cable around the house) but it would leave the charging unit near the front door. This would give us less flexibility over where and how the car was parked. However, if the unit was on the garage, then we could charge with the standard cable from any one of three parking positions.
To get armoured cable to the garage it might have to be trenched in around drains etc, which makes quite a difference - so I question whether to have this done by our local people, terminating in a connection/consumer unit in the garage. This would then make the charger installation very simple.

 

[notdodgy]

Hi,
All of the charger installations that I've seen have come off of the main consumer unit. My consumer unit doesn't have any spare capacity, but I could always have a larger one fitted. This could also have the benefit of updating my MCBs to the later safer version (RCBO?). Alternatively, I could simply get a second junction installed to take the car charger.

However, the car charger still wouldn't be in the best place for me - I'd rather have it on the detached garage. Would it be feasible to run suitable rated armoured cable (e.g. 32-40amp) as a separate feed to the garage and attach it to it's own consumer unit - which the car charger could then connect to? The current feed to the garage is only about 20amps, so I'd rather just leave that alone. Or is there a reason that it has to run from the main consumer unit?

TIA

The main purpose of the fuse / breaker is to protect the cable.
Your second consumer unit will need to be at the meter end.

The charger end will just terminate in the charger connection box or you can have a commando socket installed and the Ohme cable with a commando plug.

The commando socket will provide additional Isolation.

If there is a distance between the meter and the charger, it may need heavier cable and a local earth spike.

 

[bloggsy]

Hi -when I got my 7kw home charger installed, and for the 4 hours the electrician was here, I grilled him on everything I could think of!

From what he told me, there's no real reason to go for anything higher than a 7kw home charger as most EV's can't handle that much AC power to recharge (I think the MG ZS maximum AC charging rate is 7.5kw). 50kw public chargers are DC and different.

In my case, a spur was taken from the main supply coming into your property (after the meter), splitting the power between the main consumer unit and my home charger with a 40A circuit breaker in it's own consumer unit/box in between. So, you could run a 6mm 3 core steel wire armoured cable to your garage and into your home charger (I'm not sure whether the breaker would be by the main consumer unit or in the garage - your electrician could give you suitable advice, of course!).

Some chargers are 'intelligent' (I got a Pod Point and it's intelligent apparently) in that it connects to a central server and receives updates 'over the air'. It also has a sensor which monitors how much electricity is being used by the house and can limit the power the home charger is using, if the house is demanding more electricity which is all designed to help prevent the home charger from overloading the home circuit.

As notdodgy has said, you will need the system to be earthed (although I think there's one or two home chargers that don't require earthing) and you will also need to have your pipes 'bonded' which means they should be connected to an earth, to prevent an electrical shock. Mines wasn't and I had to have that done before my charger was able to go live.

Hope this helps!

Cheers

Bloggsy

 

[ALANB]

Hi,
All of the charger installations that I've seen have come off of the main consumer unit. My consumer unit doesn't have any spare capacity, but I could always have a larger one fitted. This could also have the benefit of updating my MCBs to the later safer version (RCBO?). Alternatively, I could simply get a second junction installed to take the car charger.

However, the car charger still wouldn't be in the best place for me - I'd rather have it on the detached garage. Would it be feasible to run suitable rated armoured cable (e.g. 32-40amp) as a separate feed to the garage and attach it to it's own consumer unit - which the car charger could then connect to? The current feed to the garage is only about 20amps, so I'd rather just leave that alone. Or is there a reason that it has to run from the main consumer unit?

TIA

Be aware that you only get the grant for the first unit, a second unit does not qualify. It's only one per address.

 

[Amun]

The main purpose of the fuse / breaker is to protect the cable.
Your second consumer unit will need to be at the meter end.

To protect the cables covered by the CU. The new main CU (or additional small one if I don't change the old CU) would cover the armoured cable to the garage. Another consumer unit could be fitted in the garage, if required.

I've daisy chained CU to outbuildings at my last property, and it was all signed off legally under the building regs.

If there is a distance between the meter and the charger, it may need heavier cable and a local earth spike.

The cable would have to be properly rated, certainly, but I believe that chargers like the Zappi do away with the requirement for an earth spike.

 

[Amun]

Hi -when I got my 7kw home charger installed, and for the 4 hours the electrician was here, I grilled him on everything I could think of!

From what he told me, there's no real reason to go for anything higher than a 7kw home charger as most EV's can't handle that much AC power to recharge (I think the MG ZS maximum AC charging rate is 7.5kw). 50kw public chargers are DC and different.

In my case, a spur was taken from the main supply coming into your property (after the meter), splitting the power between the main consumer unit and my home charger with a 40A circuit breaker in it's own consumer unit/box in between. So, you could run a 6mm 3 core steel wire armoured cable to your garage and into your home charger (I'm not sure whether the breaker would be by the main consumer unit or in the garage - your electrician could give you suitable advice, of course!).

Some chargers are 'intelligent' (I got a Pod Point and it's intelligent apparently) in that it connects to a central server and receives updates 'over the air'. It also has a sensor which monitors how much electricity is being used by the house and can limit the power the home charger is using, if the house is demanding more electricity which is all designed to help prevent the home charger from overloading the home circuit.

As notdodgy has said, you will need the system to be earthed (although I think there's one or two home chargers that don't require earthing) and you will also need to have your pipes 'bonded' which means they should be connected to an earth, to prevent an electrical shock. Mines wasn't and I had to have that done before my charger was able to go live.

Hope this helps!

Cheers

Bloggsy

You'd need a 3phase supply for a 22kw charger, which most homes don't have. So I'm looking at a standard 7kw charger with current limiting (to get round any diversity issues).

IIRC I used 10mm armoured cable for my previous outbuildings, but then I did tend to overspec everything. 6mm might be OK, but we'd have to check the capacity at that length.

 

[Amun]

Be aware that you only get the grant for the first unit, a second unit does not qualify. It's only one per address.

I'm only looking to install one unit, just trying to decide the most flexible way to install the supporting infrastructure.

 

[Les burrows]

Hi, Don’t know much about how to get around your problem, what I do know is if you want to get the OLVD grant £350 you have to use an approved installer so they should be able to tell you all you need to know and that should be your best and safest bet.

 

[Les burrows]

SORRY POSTED TWICE BY MISTAKE BUT CANT REMOVE IT Hi don’t know much about getting around your problem, what I do know is if you want to gat the OLVD grant of £350 you have to use an approved installer so they should tell you what’s the best and safest way to go could be your best bet

 

[Jake]

Be aware that you only get the grant for the first unit, a second unit does not qualify. It's only one per address.

A second unit does qualify for the grant if a 2nd EV is registered at that address.