Isolation Switch

KenD

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I am in the process to install an EV charger with Egg. There are 2 fuse boxes with spares slots. Initially Egg said that my house meets all requirements to install the charger. However the told me that I need a Isolation switch installed.

Do I need the isolation switch?

Thanks in advance
 
I've no idea whether it is required but my charger is on it's own circuit so I can easily go to the consumer unit under the stair and flick the switch off - but it'd be much easier to have an isolator nearer the charger, and I guess wouldn't add a lot to the cost at install time.
 
Are they talking about an isolator for the consumer unit or an isolator for the charge point?
The former means that the electrician can install an additional circuit without requiring DNO attendance to pull the service fuse. It's a good idea to have one and they are often installed for free when a smart meter is fitted.
 
Some EV installers like the DNO to install a main isolation switch after the service head that is carrying the main cut out fuse, prior to their visit.
It’s good idea and makes life easy for anybody to completely turn off the main supply to the consumer ( fuse ) box.
Turning off at the consumer unit, will isolate the house electrics, but the incoming side of the consumer unit if still live !.
Not the case after a main cut out, double pole isolator switch has been fitted.
The EV installer MAY have requested the DNO to check if the carrying capacity of the main cut out fuse is adequate also.
A lot of newer properties pretty much have 100Amp main cut out fuses fitted as standard.
Older properties could still be running on the smaller 60 Amp rated main cut out fuse.
This was absolutely fine “back in the day” when we never had high demand items like 12 Kw electric showers / induction hobs / electric car wall boxes etc etc.
Some wall boxes now have a load balancing facility, they attach amp clamps to the meter tails and these clamps monitor the load being pulled by the wall box.
It has the ability to throttle back on the demand by the wall box, if it detects a high load being consumed in the property.
When the high load in the house has reduced, it will allow the wall box to ramp up again.
 
I've no idea whether it is required but my charger is on it's own circuit so I can easily go to the consumer unit under the stair and flick the switch off - but it'd be much easier to have an isolator nearer the charger, and I guess wouldn't add a lot to the cost at install time.
Hi smoke, l had to have isolation switch and fuse increased to 100amp

Are they talking about an isolator for the consumer unit or an isolator for the charge point?
The former means that the electrician can install an additional circuit without requiring DNO attendance to pull the service fuse. It's a good idea to have one and they are often installed for free when a smart meter is fitted.
Sorry, yes that is what was required before my install, my Octopus supplier did isolation switch free, and UK power upgraded 63amp to 100amp free as well, O and installer increased tails
 
we we’re required to have a duel pole isolator switch installed before EV charge company would install.
 
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My Home charger (Rolec) has a dedicated isolation switch, installed by the charger installer.
I have one of the earlier Rolec ( dumb ) wall boxes myself.
It is powered from a standalone MCB breaker in an enclosure, this in turn supplies a feed via a 6.00mm twin and earth cable to the Rolec wall box.
In the Rolec wall box there is another 40 Amp RCBO that can be used to isolate the power to the box itself.
But remember there is power still being supplied to the wall box, until the RCB upstream is fully isolated.
 
Just to clarify my installation, I have an isolator upstream of my consumer unit but my installer also fitted an isolator adjacent to my Hypervolt.
isolator.jpg
 
Scheduled the Isolation switch with Eon this Thursday. Cost £98, Eon doesn't give free Isolation switch if installing smart meter at the same time. The Eon services on WhatApp is good.
 
Scheduled the Isolation switch with Eon this Thursday. Cost £98, Eon doesn't give free Isolation switch if installing smart meter at the same time. The Eon services on WhatApp is good.
Wow, the switch that Octopus fitted for free was to switch of consumer unit completely, which in turn isolate the charger as well,
 
Mine was free along with tails upgrade and then it was also free to be de looped
 
Appointment for switch installation booked for 6-8 pm last night. The EON engineer didn't turn up and received cancellation notification about 6:30pm. Rebooked for 21st Apr. Filled a complaint and try to push the appointment early, not sure if it helps.
 
@KenD

Who is fitting the actual charger? (Sorry, just re-read your first post to this thread and see it is Egg.)

I needed an isolation switch installed when my charger was installed. The installation company took care of installing both, on the same day. Can Egg not do this for you; it doesn't require your DNO or electricity supply company to fit it. Especially if you now have to wait a further 6 weeks for EON to return.
 
Fitting an isolator requires removal of the service head fuse and that will involve breaking a tamper proof seal. Normal electrical installers have no legal authority to do this.
 
yes Alb is right. Egg told me that only the supplier can install the Isolation switch and there is risk to be sued if they install it.
Having looked back, Egg needs to take some blame as well. I could had install the isolation switch earlier. I have sent all photos of the fuse boxes, route of the cable and location of the charger in Nov 2022. I am told that all ok and just to book a date for installing the charger once I get a date to collect the car. I am only told that I need a isolation switch when booking the date. Luckily or unluckily that I found a slot from EON to install the isolation switch last night. EON eng didn't turn up...
I need to rely on public chargers for a while, which cable to buy, normal type 2 7 KW or type 2 22KW?
 
yes Alb is right. Egg told me that only the supplier can install the Isolation switch and there is risk to be sued if they install it.
Having looked back, Egg needs to take some blame as well. I could had install the isolation switch earlier. I have sent all photos of the fuse boxes, route of the cable and location of the charger in Nov 2022. I am told that all ok and just to book a date for installing the charger once I get a date to collect the car. I am only told that I need a isolation switch when booking the date. Luckily or unluckily that I found a slot from EON to install the isolation switch last night. EON eng didn't turn up...
I need to rely on public chargers for a while, which cable to buy, normal type 2 7 KW or type 2 22KW?
UK ZS only Needs single phase 32 amp cable but a three phase 32amp will do the same job but will work on other cars that accept 22kw
 
@Alb @KenD

Sorry, in my installation, fitting the isolation switch did NOT involve removal of the service head fuse; it was connected to a spare socket on my CU. The installer added an RCD unit to that spare socket and then connected the isolation switch.

I believe my DNO are fully aware of exactly what was done by the installer; certainly I know they corresponded with each other on several occasions, including when, after installation, I discovered that the charger was repeatedly "disconnecting", necessitating a reboot via the isolation switch. The problem turned out to be that the incoming mains voltage, which has, by law I believe, to be between 216 volts and 253 volts, was actually up to 258! Hence, the charger's overload protection was being activated.
 
it was connected to a spare socket on my CU. The installer added an RCD unit to that spare socket and then connected the isolation switch.
Yes that's what I understood was meant by isolator and how I envisaged it in my post upthread.
 
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