DIY V2L cable

[Tig170]

.... only if you are feeding back into the grid, these days its not worth it (3 - 5 pence / KWh), just use the settings (frequency shift) to stop any back feeding, and you can do as you please.

 

[Tig170]

So now the MG4's have both gone back I have no need for the V2L cable that I built at the begining of this thread.
Only powered up to test it, never used since.
Parts are roughly £70 plus time to make it work with the mg4 and the other MG's.

So if anyone is interested and doesn't have the skills to make one up themselves.
I'm offering this one up for sale if anyone is interested.
Just looking to get my money back for the parts, but you will receive a fully rewired for MGs and working V2L cable and I will also include tracked and insured delivery in the price which will be a tenner probably too.
Like I say never been used apart from powering up to test it then it went back in the box as I rejected both my MG4's
5 meter cable
waterproof sockets

Looking for £70
Send me a pm if interested

View attachment 13309
Cheers

I'm doing the same (with bits via Ali express < £50 delivered), the only thing i did find was that if if left on the AC in the car, I got to 4.4+KWh (max was above 5.3?) discharge, which caused the car to smell (electrical), a bit - so do switch off your AC if you are pulling a few amps.

 

[Eclectic]

PP and PE
Most cables already have a 680 in place already between those 2 so its just a case of swapping it out.

View attachment 12586

You also need to connect cp to pe - some MGs don't like cp "floating"

 

[Tig170]

... I must admit that in my system - i simply swapped the "existing charing" resistor for a "discharging" one (I think they were £2.80 delivered on amazon for 10)

 

[Ayoull]

.... only if you are feeding back into the grid, these days its not worth it (3 - 5 pence / KWh), just use the settings (frequency shift) to stop any back feeding, and you can do as you please.

It's to do with the prevention of the passing of a fault from any generation (that a battery storage system is classed as) to the DNOs network at loss of mains as you could kill a jointer or linesman on the network, opposed to exporting back power.

 

[Tig170]

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must admit that the v2L cable is working well as a simple top-for our grade G energy efficiency house. We must be taking out (at max 2kw/hr)10-20KW from the Mg4 each day -for at least this year (till may 24) in that off-peak charging is 4.5ppkh via EDF from (00:-05:00am each day!)

 

[Purclewan]

---

must admit that the v2L cable is working well as a simple top-for our grade G energy efficiency house. We must be taking out (at max 2kw/hr)10-20KW from the Mg4 each day -for at least this year (till may 24) in that off-peak charging is 4.5ppkh via EDF from (00:-05:00am each day!)

Just out of curiosity, how are you feeding the output from your car to your house? Have you a method for doing it automatically or do you have (as I presently have) an Island solution as previously described with a throw over cct. I am looking for an automatic solution taking into account all the issues raised during this discussion on not feeding back into the grid.

 

[Tig170]

All our loads are on AC Out (off grid mode - i.e. no backfeed on AC IN - VE Multiplus II GX - 5000). Currently have a very manual system, for us, we only need 7.5kw to run the house / day, which is the battery capacity, so have limited AC IN to 10A, which just about charges the house battery fully overnight - the car is on its own consumer unit for charging.


Before christmas (when we needed to topup the house battery during the day), as it was colder / had too much heat loss from house, I just swapped the charger/invertor over manually ( at present currently using a simple 3 pin plug / socket) either from the car, or the mains.

... but am a bit like yourself maybe (the VE Quattro would solve this), it would be desirable to have an automated system, but just at present a manual system suits us just fine in plugging in one or another (its also a bit of a pain, on the cars menu system - i.e. you have to get in (or just push down on the centre of the drivers seat), and then switch it on via the menu. Also 10A is within tolerance on the MG4 @ 2.3Kw, but remember to switch off the aircon, otherwise the display will show 5Kw+


... longer term, im not 100% what to do, as our current system is very dependant on cheap overnight electricity (you can only get octopus at present @12.5p off-peak rate?), which in our case lasts another 18 months, longer term I think we’ll need more battery storage (maybe dont need this as the MG4 covers this!), but getting in solar, which will limit the reliance on the grid to Nov-Feb in the UK.

..... also thinking of trickle charging the house battery on the DC side from the AC230v out of the MG4 - as a trail was thinking on getting RS Stock No.:200-6362, to see whats happens

 

[Purclewan]

All our loads are on AC Out (off grid mode - i.e. no backfeed on AC IN - VE Multiplus II GX - 5000). Currently have a very manual system, for us, we only need 7.5kw to run the house / day, which is the battery capacity, so have limited AC IN to 10A, which just about charges the house battery fully overnight - the car is on its own consumer unit for charging.


Before christmas (when we needed to topup the house battery during the day), as it was colder / had too much heat loss from house, I just swapped the charger/invertor over manually ( at present currently using a simple 3 pin plug / socket) either from the car, or the mains.

... but am a bit like yourself maybe (the VE Quattro would solve this), it would be desirable to have an automated system, but just at present a manual system suits us just fine in plugging in one or another (its also a bit of a pain, on the cars menu system - i.e. you have to get in (or just push down on the centre of the drivers seat), and then switch it on via the menu. Also 10A is within tolerance on the MG4 @ 2.3Kw, but remember to switch off the aircon, otherwise the display will show 5Kw+


... longer term, im not 100% what to do, as our current system is very dependant on cheap overnight electricity (you can only get octopus at present @12.5p off-peak rate?), which in our case lasts another 18 months, longer term I think we’ll need more battery storage (maybe dont need this as the MG4 covers this!), but getting in solar, which will limit the reliance on the grid to Nov-Feb in the UK.

..... also thinking of trickle charging the house battery on the DC side from the AC230v out of the MG4 - as a trail was thinking on getting RS Stock No.:200-6362, to see whats happens

Thanks for the reply, sounds like you are trying to do something similar to me but are a few months ahead.

My biggest issue with the manual changeover is the multiple Raspberry Pies I have running to control the home automation, the heating control system (Underfloor) and my MQTT server.

Sadly Raspberry Pie's do not always take well to power interruptions which can corrupt the boot disk, not great when all your automation is running on them so I need to do a controlled power down and then reboot after switch over.

Trying to build a UPS for the Pi's that will also do a controlled power down but not there yet.

On a different note, I keep hearing that the MG4 cannot be locked when in V2L mode and that the 12V battery discharges as the car is still on. Have you had any experience of this?

 

[Stageshoot]

I'm doing the same (with bits via Ali express < £50 delivered), the only thing i did find was that if if left on the AC in the car, I got to 4.4+KWh (max was above 5.3?) discharge, which caused the car to smell (electrical), a bit - so do switch off your AC if you are pulling a few amps. View attachment 13310

View attachment 13311

Not surprised you smelt burning with that cable at 5kw output, thats max 13amp 2.7Kw cable, run that over that spec for any period and you are in for a world of pain.

We have wired back to the house using proper 7Kw Capable Cabling and the car outputs 30amps at 220v (7Kw with no issues or burning smells!)... I would upgrade your cable if you are going to do it long term..

 

[Stageshoot]

@Tig170

Which software version is your car running, as on our Trophy Ver R30 it does not show the discharge power on the car screen.

 

[thejaybeeok]

I understand the need to save money, but I can’t believe some of the V2L cables and adapters people are buying.

Some have no IP rating, use undersized cables, have no thermal protection, have no CE markings.

Please stay safe.

 

[Stageshoot]

I understand the need to save money, but I can’t believe some of the V2L cables and adapters people are buying.

Some have no IP rating, use undersized cables, have no thermal protection, have no CE markings.

Please stay safe.

Exactly these 13amp cables should have a 2k Ohm resistor in them the same as the official MG version to hardware limit them to 2.2Kw

The 470 Ohm resistor allows the car to output 7kw and doing so through the thin 13amp cables is a recipe for disaster.

 

[Deleted member 10041]

If an electrician came to the house to do a job and fitted the wrong amp cable for the job people would quite rightly refuse to pay him and possibly report him to a regulatory body yet when it comes to people doing a job their self suddenly they are happy to cut a few corners to save a few quid.
Hope nobody has to regret their decision.

 

[Purclewan]

Exactly these 13amp cables should have a 2k Ohm resistor in them the same as the official MG version to hardware limit them to 2.2Kw

The 470 Ohm resistor allows the car to output 7kw and doing so through the thin 13amp cables is a recipe for disaster.

Can only agree that we may see some dangerous situations arising because of lack of understanding or basic knowledge of electrical circuits. I think some of the YouTube videos I have seen are definitely giving a false sense of how easy it is to connect your home to your car (it is easy but only using the correctly rated cables and wiring).

I want to use V2L for load balancing and backup supply in my house and that's part of my rational for buying an electric car but I'm following a similar route to Stageshoot.

I already have proper cabling from my Garage to my house as part of my backup generator system together with a full isolation switchover from Mains to Generator at my consumer unit.

For my V2L cable, I am making up my own short cable using 4mm artic flex which is rated at 32A or approx 7KW, about 3KW over my normal load. This will be hard wired into my existing generator input in the garage. I did consider using 6mm cable but found that would be just too thick to fit the adapter.

I still need to work out the earthing situation to ensure that my ECCBs and MCBs in the consumer unit work as intended (any advice Ayoull?) but whatever happens, I will only do it all if I'm confident I am not going to burn my house down or worst, kill someone as a result of trying to save a few shillings.

 

[Sloucher]

I think it about time that someone, with the requisite technical and industry knowledge, once and for all lays out the dangers involved in trying to use V2L to power their house to the average joe on this forum.

Fine, the guys discussing it on here currently (pun NOT intended) may seem to know all the problems associated with connecting an independent AC source, i.e. the car or generator, to a house which is connected to the national grid. I am not criticising them per se, but I would hate for anyone with no electrical knowledge read these posts and think "oh, that's easy, I can do that".

Unless you know what you are doing - and you are sure that your DNO knows all the details of your system, please, please do not try to use V2L as V2H. In other words, if you don't know what is involved - just don't - unless you want to be responsible for possibly electrocuting a linesman. Just stick to using V2L for what it is intended for - running 240v ac appliances in isolation.

 

[Ayoull]

I am a DNO design engineer and have on numerous posts stated V2L is dangerous and against the requirements of the ESQCR in that you must not cause harm or damage or distortion to the network.

You are not permitted to connect any power backup or generation device to a DNO connected premises without the DNO advising it is permitted to do so, and if it isn't type tested you will have to provide evidence that you have undertaken industry standard tests to show that it complies with all the requirements of G98/G99 as applicable.

If you are using the system in island mode you will require a grid level earthing system that does not induce a voltage in any DNO earthing system or electrode and a copies of a RENA (or other approved study type) study showing this, along with copies of electrical design calculations for contributiory fault levels and earth grading charts, all this has to be submitted to the DNO prior to commissioning.

If this is not done the DNO can request to disconnect your system and if you refuse they have the statutory right to disconnect you due endangering others due to the potential to cause harm, injury and potentially death to others.

As under fault conditions if you have not done all of the above you cannot prove your system won't potentially kill a jointer, engineer or linesman working on the network as you can't prove you've designed your earthing system to not induce a voltage in the DNOs earth, and cannot prove your system has been designed or approved for the way in which you are using it.

 

[DangerousDoug]

I'm an electronics engineer and do understand the issues associated with connecting VTL directly to house wiring. Therefore the only "domestic" use I'll make of my VTL cable is to separately connect the UPS I have feeding my internet/server environment. I have an EPS UPS unit feeding my internet router, DNS server (raspberry pi), home file server (Linux microserver) and a couple of other Pis. I can easily run an extension lead from the (home made - as this thread) car VTL cable in through my office window. We have a solar/battery system with auto change-over isolator switch, so the house can be powered from the solar battery in case of power cut, but the car can keep the internet running (our most important electrical system!) and laptops/phones charged should there be a longer term power cut.
The other use I intend for the VTL cable is in case one of us is stranded with a flat EV battery (we both drive EVs) so the MG4 can be used as a "recovery vehicle" to charge the other.

 

[Ayoull]

Just stick to using V2L for what it is intended for - running 240v ac appliances in isolation.

That's it V2L is basically just using your EV like a giant suitcase Genny or a small battery pack like you buy for emergencies for your phone.

I hope I'm wrong but can envisage someone getting hurt and car manufacturers disabling it via an update as they are partially culpable under H&S legislation for not designing out an extreme obvious risk scenario to anyone who works for a DNO or is competent electrically.

 

[Sloucher]

@Ayoull and @DangerousDoug , many thanks for your erudite explanations and warnings associated with the mis-use of the V2L feature provided on our cars.
Hopefully they will cause people to think twice before mistakenly thinking that V2L (vehicle to load) and V2H(vehicle to home) are one and the same.
So far, only a few vehicle manufacturers provide true V2H and MG is not one of them.