Welcome to the forum. In the circumstances described, it would seem that you are fully aware of the negatives around granny charging, but have little alternative, other than not to do that and use public charging. You have already taken all possible steps to limit risks, so there is little else you can do without spending a lot of cash. The plug in the granny lead will already have a thermister device that cuts power if heat builds up there, but the socket has no such protection. Best you can do for now is keep a close eye on the socket/plug connection and make sure that it remains warm rather than hot.

The remaining technical risk will then be from the PEN fault issue, which is not discussed much but is still there. There are stand-alone solutions but they are not cheap. Check on-line about that problem with UK mains supplies. Or use the "Search Community" box above to find threads on that subject.

Most likely you will decide to note the issue but not do anything about it as you may be moving soon. And tbh there are many thousands of people who use a granny charger in the way you envisage without any problems. That doesn't take the PEN problem away, just makes it a fully informed decision.

 

The only thing I would add is to stop the charge in the car or via the cars app, rather than just switching off at the mains. Kinder on the on board charger and the mains switch.

 

Are you able to drop the current from 10A down to 8A either in the car or on the EVSE?

 

The house is rented and you are within your rights to use a granny charger, the car is leased and under warranty. You'll be fine 😁.

 

Thanks for the replies, very useful information. I will from now on stop charging from the car screen.

Yes, I can drop the charge to 8 A, this drops the miles added by2 per hour.

So a plug in RCD is not worth adding?

Thanks again.

Steve

 

So a plug in RCD is not worth adding?

Its probably worth getting an inline rcd short extension lead(not as an extension but to provide rcd protection, toughleads make a 2m version and i wouldnt want one longer than that for this purpose) if theres no rcd at all in the consumer unit(there should be one for sockets likely to be used for equipment outdoors) make sure its a type A rcd if you do that as a type ac rcd isnt suitable but is quite common) toughleads seem to make good quality ones

I wouldn't recommend a plug in rcd as they are quite a bulky plug

 

All compliant granny chargers contain an integral 6mA DC RCD, plus a standard 30mA AC RCD - there is no need to add an external RCD and if anything, it likely makes the situation less safe as you have added extra contacts into a relatively high power load.

 

Its a pretty minimal if any extra risk on this situation(with a competently built lead) unless your also testing the socket its all plugged into which no one is generally doing, i get they should have a built in rcd but for a 3 pin charger with no rcd protection at the board id still want a seperate inline type A rcd

 

Since 1 June 2020, the Electrical Safety Standards in the Private Rented Sector (England) Regulations 2020 mandate that all rental properties must have electrical installations that are safe.

Landlords must provide an Electrical Installation Condition Report (EICR) every 5 years.

No genuine EICR would allow a board with no RCDs.

Obligated to remedy within 28 days.

A granny charger is unsuitable for charging an EV.

 

A granny charger is unsuitable for charging an EV.

Ahem. A granny charger is a suitable method for charging an EV, provided appropriate precautions are taken with their use, which rules out certain use cases. In general, granny chargers are not rugged enough to be used for frequent charging, although this will vary from make to make - I had no issues using one as my only charging method for two years in a rented property, but I only had a plug in hybrid at the time with a much smaller battery.

 

And the granny charger has an RCD! I know some may not feel comfortable using that but it is a fully functional RCD implemented in the internal electronics of the granny charger, and unlike a type B RCD it is DC sensitive as well as AC sensitive.

As for open PEN protection, that varies. There are granny chargers that implement one of the types of open PEN protection as they have a contactor between the vehicle earth and the plug earth. If I put a meter on my VW granny charger then there is no connection between vehicle PE and plug PE when unplugged. A power failure to the granny charger (voltage out of range), as will typically occur in a PEN fault, will cause this contactor to open.

 

The presence of an RCD inside the appliance or lead does not remove the requirement for RCD protection at the fixed wiring end. EVSE lead with residuals is considered supplementary protection.

Granny chargers plugged into a 13 A socket are explicitly outside the scope so your testing is moot.

This situation as described by OP is stacking risk on risk and I find it bonkers that others are rationalizing unsafe practice just to dodge cost or hassle.

Just pointing it out from the opposing side so the risks aren’t glossed over.

 

rationalizing unsafe practice just to dodge cost or hassle.

I am happy to meet the cost and hassle of a proper EV charging unit, but have an unsympathetic landlord who won't allow the work to be done. So I use a granny charging unit, limited to 6 amps, checked over by a professional electrician. I only need to charge the car (42.5Kw battery) once every three weeks, never at night and always monitoring for undue heat. There must be tens of thousands of EV owners who use granny chargers carefully and sensibly without any issues.

 

Saying “tens of thousands do it” isn’t evidence of compliance or safety, it’s just normalisation of bad practice.

 

The requirement to have RCD protection on sockets is one for a landlord (or homeowner), it is not anything to do with a tenant, and I cannot think of any law that would make using a non-RCD protected socket illegal for a tenant. Sure, it's not particularly safe compared to the state of the art, but the liability is entirely with the landlord. If you're a private home owner, you're not legally required to ensure your installation is up to any code unless it is modified or extended. You might have difficulty when it comes to sell the property, as some solicitors would insist upon a property having a recent EICR, but ultimately it's a risk for the buyer and seller to agree upon.

And in any case, granny chargers have a built in RCD. I know you might not think this matters, but it's a fundamental requirement of any EV charging equipment. Fixed EVSEs do not require an RCD if they are built into the EVSE, so why would you be worried about a granny charger, I do not know. Yes the socket should have an RCD, but does it make this situation any less safe? No, I don't think so.

As for PEN protection, I did a little test last night with my VW granny charger, which is kept as a spare in case my main charger fails me. I found that when the input voltage dropped below 140V ac the earth contactor isolated itself and the charger shut down (this is out of spec for the 722.411.4.1 iv method which requires 207V min., but this device was released before that became a regulation). I also found that by adding progressive amounts of insulation tape around the earth pin that the charger does some kind of earth impedance test and will refuse to power up if the earth impedance is high. I'm trying to think of a way I could simulate a better test here, perhaps I could deliberately add impedance to the N-E and tie them together at the source, as I'm not sure if the charger is measuring N-E impedance or using some other mechanism to determine the PE health. But it does appear that there is more going on inside these devices than some think.

I don't have hundreds of pounds to spend on the copy of the IEC standard that portable EVSEs are made to, but I would be quite surprised if they represent the hazard suggested, given car manufacturers still supply them with their vehicles (aftermarket or sometimes as standard) and they are sold on the open market by the likes of Screwfix, Toolstation, Halfords...

 

Are there any statistics as to how many people have been killed or injured through the use of granny chargers?

 

A pointless excursion because the regs can't effect what you do with a socket. Just because you can doesn't mean you should.

What else can it do except say it shouldn't be done, just like don't pme supply to a caravan via a 13a socket, or don't wire an immersion via a 13a socket or fcu and recommend suitable precautions are taken.

Besides we have BS1363-2 EV for a reason.

These endless topics on this issue is extremely annoying, especially this "waaaah waaaah my OEM provided one" despite quoting no product standards or giving examples of products for other markets. Please let me know how your granny charger goes in France... oh wait it's banned.

Be informed and compliant or not. It is bonkers that people think stuff that physically fits means it's OK or not knowing a software-based RCD in a portable lead are supplementary, not substitute for a compliant installation RCD. Beggars belief.

Seeing as noone even wants to bother im not going to reply further, and people wonder why we describe the UK as decades behind elsewhere electrically.

 

The same software-based RCD you bemoan in a portable charger is just the same as is used in many wall mounted EVSEs which do not require an RCD at the consumer unit, so what difference is there? For instance both PodPoint and EO supply EVSEs with such RCDs built in, nothing wrong with doing the test in software provided the software is implemented and tested according to standard. Besides, combined AFCI+RCD breakers are using software now because it's easier/cheaper to build both functions into one microcontroller that throws the contacts open (the design of which is pretty similar to a contactor, it's just latching instead of momentary). Of course, you have to trust software, but you do the same anytime you press the accelerator pedal in any car made in the last 20 years, it's all software controlling the engine/motor.

 

Yikes.

 

Dog with bone.

 

Hi, Thanks for allowing me to join. Just leased a Leapmotor C10, first EV. I knew the car/driving would be a learning curve, but had not really considered it is nothing compared to the charging issues. Rented house, so knew my choices would be limited, especially as might be moving in next few months. Read lots of opinions re using Granny Charger as main charging. No real point in going over that here as I really have no choice, at least for the foreseeable. What i am trying to get my head around is how to use it as safely as possible. Complicated by the fact there is no RCD on the consumer unit (speaking to landlord about that, but nothing will change quickly, if at all). So.........., how best to use the Granny Cable. I have tested the sockets I intend to use with a socket tester, all appears fine. in the socket I have been using for the last few days the plug (where it meets the socket) has not gone above 21 degrees, even after a few hours (using infa-red gun gadget). Car app shows Current 5.5A Voltage 351.8V Power 1.9kW. Apart from Stop Using It, which I am sure some will suggest, what are my options to make it as safe as possible? I am not doing enough miles to make the overnight low rates available worthwhile so am staying on the standard rate (20p per kWh), so dont need a timer as I can charge anytime. I envisage topping up for a few hours maybe 3 times a week, only during the day when we are here. I have seen plug in RCD's on Amazon, is one of those worth adding between plug and socket? Socket is in garage and cable will run under the door, so no weather issues and no extension cable needed. Is there anything else I can do to improve the safety? Thanks (sorry for such a long first post) Steve

How I hate that term, granny charger! I'm not a granny and hate gender specific labels. Anyway, wanted to share my experience of using my domestic electric supply to charge my MG4 for the past 3 years with no problems at all. Firstly, bear in mind the advice re these types of batteries generally, whether in smartphone or EV. For longevity and health of battery keep it between 30 and 80% whenever possible. MG actually advise this. Avoid fast charge when possible, because it degrades battery faster. When charging at home, I use a normal socket, a normal albeit slightly heavy duty extension lead, and bought a compatible extension cable for car from Amazon. The normal extension lead is fed through my letter box and connected with the car lead. Two key safety points: never try to charge faster or at a higher rate than your normal domestic appliances, and keep the extension lead from property extended. Do not allow it to coil. Mine runs the length of the house, along the skirting board. This is to avoid generating too much heat, or overloading your socket. There were reviews on Amazon where people's sockets had burst into flame! So, a long, extended heavy duty extension cable from socket, through letterbox, a long, low voltage charge (selected on car extension cable), plug into car extension cable and off you go.

 

Maybe everyone will now realise why we have regs. 😅

 

Compliance with electrical regs is already a baseline assumption of cover.

In the event of a fire, the insurer has a straightforward way to decline or reduce payout: non-compliant installation.

 

Electrical regs cover the fixed installation, not a portable device, such as a granny charger. You are not breaking any electrical regs simply by plugging a portable appliance (granny charger) into an electrical installation that is already compliant for use with other portable appliances. The regs require that any socket that has been installed specifically for EV charging meet some extra requirements, but that does not prohibit you from plugging a granny charger into a socket that was not installed for EV charging.

Besides, all of your arguments seem to revolve around compliance, rather than any practical problem with using a granny charger.

 

I thought the BS standard for UK sockets was 10 amp load continuously for 24 hours or more? The quality MK ones seem to offer this. Should be fine to use a granny charger at 10 amps.

If you have granny chargers with thermal cut outs in both ends then nothing untoward should happen.

Many house fires start due to have shiny crap hanging in the window that sets fire to furnishings as the sun reflects onto something flammable.

 

I thought the BS standard for UK sockets was 10 amp load continuously for 24 hours or more? The quality MK ones seem to offer this. Should be fine to use a granny charger at 10 amps.

If you have granny chargers with thermal cut outs in both ends then nothing untoward should happen.

Many house fires start due to have shiny crap hanging in the window that sets fire to furnishings as the sun reflects onto something flammable.

No regular UK socket is type tested for such a load. There is a distinction between purely resistive and inductive loads.

Even the newer cyclic test isn't continuous for that long. It's 8h.

You need to remember the original type test is absolutely ancient compared to the modern things we have now. Back in the day you'd be lucky if you had a kettle.

 

Yep, providing the wiring to the socket isn't in good condition and the connections to the socket properly clamped up, and 1 ohm resistance in the line at 10amps will cause a 10v drop across the plug which emits 10watts of heat which over hours of use could melt the socket.

BTW when my daughter bought her house quite a few years ago they got an electrician friend to check it over and he found faulty wiring on a couple of sockets.

 

Technically, all sockets that were compliant when installed remain compliant even if the regulations subsequently change. So that someone using such a socket to charge a car using a portable EVSE is also acting legally. It's only new circuits that are installed for the purpose of charging an EV that must comply with the regulations in force now.

We all understand that this is somewhat unsatisfactory, but we are where we are. And to accuse people of failing to comply with regs by using a historic socket is just wrong.

 

Technically, all sockets that were compliant when installed remain compliant even if the regulations subsequently change. So that someone using such a socket to charge a car using a portable EVSE is also acting legally. It's only new circuits that are installed for the purpose of charging an EV that must comply with the regulations in force now.

We all understand that this is somewhat unsatisfactory, but we are where we are. And to accuse people of failing to comply with regs by using a historic socket is just wrong.

That the entire point, retrospective application isn’t how wiring regs work.

Existing circuits may be used for new purposes only if they are verified suitable. A historic socket is not suitable for EVSE loads.

This is now just circular nonsense.

 

Thanks for all the replies, I had no idea this thread had gone on so long. I dont understand most of what has been discussed here.

My charger was supplied with the car, I had done some research so did not discuss it with the dealer. I did not know at that point about the house wiring though. I don't suppose many EV salesmen say to their potential customers "....you do realise you will need to spend another £1000 buying a charger for this at home ...."

The landlord is going to upgrade the electrics. I am using the GC for a max 4 hour approx 2-3 times a week, monitoring the plug/socket temp, it rarely goes above 17, unlike my tumble dryer that spends most of its time at 33.

Thanks again.

 

Thanks for all the replies, I had no idea this thread had gone on so long. I dont understand most of what has been discussed here.

My charger was supplied with the car, I had done some research so did not discuss it with the dealer. I did not know at that point about the house wiring though. I don't suppose many EV salesmen say to their potential customers "....you do realise you will need to spend another £1000 buying a charger for this at home ...."

The landlord is going to upgrade the electrics. I am using the GC for a max 4 hour approx 2-3 times a week, monitoring the plug/socket temp, it rarely goes above 17, unlike my tumble dryer that spends most of its time at 33.

Thanks again.

Great news.

 

I once boiled a 3kW kettle twice in a row, I felt how warm the plug was, shat my pants and therefore had to boil it again.

I'm sure kettles are so dangerous that you need to keep some water closely, just in case.

Having replaced an outdoor socket for one of known quality some time back when I did need to granny charge I was bricking myself in case the feds turned up and wagged a finger.

The plug and socket actually stayed a lot cooler than my kettle one did though.

Now, where'd I put my fresh dacks???

Gaz

 

You can joke about, but bottom line is you’re normalising corner-cutting, all to dodge spending a few hundred quid on a proper circuit.

 

My electricity use for my ev last year at normal tariff was £188.21 if i had a ev tariff for the risky overnight charge it would have been £70.32.

less than 1000kwh a year does not warrant a 7kw evse

 

I thought it would be an interesting question to ask how long does a smart charge point last for on average. The end point being if it fails completely or it has lost it's smart function for whatever reason. I asked Chat and it gave an estimate for retaining it's smart functionality as five years and 10 years if you use it in dumb mode. I'm sure YMWV. I was trying to ascertain what the average yearly cost might be given an installation or replacement cost averaging £1,000. Because that's what should be added to the cost of charging when comparing tariffs and of particular importance when your yearly mileage is low.

 

Replacement cost varies.

For example binning one chargepoint for another might cost less than £200 to fit plus the cost of the chargepoint.

Another example is if a Wallbox Pulser was to fail within warranty they send an engineer out to swap the unit FOC *at keadt that gad been the case)
Indra Pro used to have a much better warranty, back when it was 5 years I was given the impression that it would be dealt with at no cost but niw the warranty us just 3 years there coukd akso be additional charges.
Pidpoint will try to pretend something faulty needs swapping out entirely at a fuscounted cost of £600 but within the warranty it's free unless you're deemed responsible for it failing.

If people are replacing a like for like chsrgepoint outside of the warranty then the cost will be much lower than a full install so it depends very much on what they are changing to, if it's different then a bit of fiddling required may push a very cheap swap cist up a bit.

Swapping from a working unit to a different unit for compatibility reasons akso allows sone money back for the old unit assuming it's in good order.
For example I sold my old Podpoint after I replaced it with an Indra. The replacement cost was around £180 so with a bit of money nade on the Pidpoint and getting the Indra cheap the overall cost was barely any different to the cost of an Indra Pro from a reasonably priced retailer.

The costs of a full install are ydyally a one-off and future changes should be a lot cheaper.

Rather than viewing the cost of a chargepoint as related to the tariff it's better to get something with varied compatibility and look at it as an incudental cost to owning the car.
Just as a phone charger has nothing to do with Vodafobe or EE but more with your Samsungke or Apple phone.

I did out my Podpoint for an Indra because I wanted to use OVO but that was more a result of Vauxhall making a very poor decision to push Podpoint onto people in the first place.

Gaz

 

I have the OVO EV charger warranty, it's currently £1.75 per month on a promotion and I expect it will be more next year. There is a £250 excess if the charger is over 10 years old.

 

Which chargepoint does that cover/what do you have?

Gaz

 

If you can get a warranty at a reasonable price then that is useful. Some companies treat failed units out of warranty like electronic waste and that should be part of the consideration as well.

 

Aviva Zero car insurance cover includes home charger cover: