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EV charge points


lizzie

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Good idea.  I fitted two charge points, one either end of our drive, a 30A one at one end and a 15A one at the other end.  Watch out for cost, though.  There are many EVSE options, and Rolec products are good, and that supplier seems to sell them at a reasonable price, but more than Rolec sell direct for  Also watch for zero cost offers, as these rely on selling your personal data via a data link in order to pay for the unit, and you may or may not be concerned about the privacy implications, targeted advertising, etc, that may be associated with this.  Rolec offer a subsidised install that is good value: http://www.rolecserv.com/ev-charging

 

One of the best quality, low cost, EVSE units are those based on Open EVSE (https://www.openevse.com/ ), a very nicely designed, open source, EVSE design that can be purchased in several different forms.  I've purchased parts from this firm: http://evbitz.uk/EVBitz.uk/Welcome.html a few times, when building the EVSE units I use (I've made four EVSE's now - MUCH cheaper than the commercial units!), but their ready built units are too pricey, in my view.  There are only about £30 worth of components inside an EVSE box, most of the cost is the case, cable and car connector.

Edited by JSHarris
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 i am no expert but why panic?

As long as you are able to pull cables from your power supply to where you would be placing the power point and a relatively easy install, I wouldn't be spending £300 on something i don't know will be compatible with the car i may buy in the future.

 

I still remember the guy who "future proof" his home sound system with a kenwood 50CD auto changer under his staircase, awesome at the time! 

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Good point, if you think that the J1772 EVSE standard may change before you get around to buying an EV, then just putting a hefty cable in place is probably a better bet.  In my case I already had a plug-in car, plus I'm pretty sure that J1772 will be around for another decade or so, so I fitted one standard J1772 tethered cable EVSE unit plus one fitted with an IEC62196-2 socket, as fitted to public EVSEs.

 

The argument in favour of fitting an EVSE now, though, is that they are still subsidised.  Whether or not that makes sense depends on how long the subsidy is likely to continue.  If you want to future-proof, then fitting an EVSE with an IEC62196-2 socket on the front, rather than a tethered J1772 charge lead and connector, guarantees that the unit will be OK for the next 20 years or so at least, probably a lot longer, as the IEC62196-2 charge point infrastructure is widespread in the UK and Europe. 

 

Given that the IEC62196-2 socket has been adopted as the standard fixed charge point connector, if, for some reason, EV manufacturers decide to bin the existing J1772 vehicle connector, then the EVSE will still be fine, as the IEC62196-2 connector supports single or 3 phase charging at up to 32A per phase (but realistically, home charging is very unlikely to ever normally exceed somewhere around 7.3kW single phase, because of local grid limitations).  7.3kW equates to roughly 25 miles range per charging hour at the moment.

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Thank you all. I dont pretend to understand all the technical stuff and I certainly couldn't build one, wiring. a plug is a major for me.

 

I think I will be changing my car next spring so not too far in the future but I am not sure which make or model yet which is why I thought this looked a good option as I could charge anything with right plug in cable. I also have friends with ev and was hoping to be able to let them charge when they visit.

 

I have a friend who worked at Tesla on the design side now moved to a fruity competitor on the R&D for their offering which is still way down the line.  He tells me all new homes and refurbs get universal EV charging points installed as a matter of course now.

 

 

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Sadly there is no "universal" EVSE (Electric Vehicle Supply Equipment).  Currently there are three main systems, none of which are truly compatible with each other. 

 

The most common, and the one that's found on the vast majority of public charge points, is the IEC62196-2 Type 2, usually with either an IEC62196-2 socket, or a tethered lead with a J1772 connector fixed on the end. 

 

The next most common is the Tesla-specific Supercharger, which is unique to Tesla and not used by any other manufacturer.  Tesla have done a good job of setting up Supercharger public charge points, but only Tesla cars can use them.  As a backup, a Tesla can slow charge using a separate IEC62196-2 Type 2 connector, rather than the Supercharger connector, which means the Tesla is compatible with all the IEC62196-2 public charge points, albeit at a slow charge rate.

 

The final standard is CHAdeMO, which is a DC fast charge standard, similar in some ways to the Tesla Supercharger (but not compatible with it, AFAIK), but it's not at all common here in the UK. 

 

If you're thinking of getting a Tesla, then look at getting three phase power in, so you can install a home Supercharger, but be aware that this will only charge a Tesla. 

 

If you want the closest there is to a "universal" solution, then look at installing an IEC62196-2 Type 2 EVSE, without a tethered J1772 lead and connector, but with an IEC62196-2 socket on the front.  That should be pretty future proof.  I would strongly recommend installing a 32A unit, which will allow home charging at around 7.3kW or so.  The majority of newer EV can accept a 32A charge now (often colloquially referred to as a "7kw" charger), and it very much looks as if the IEC62196-2 connector is going to win out from the other AC charge connector options.  Virtually all the non-Tesla public charge points that don't have tethered charge cables (so need you to provide the cable) use the IEC62196-2 connector - in fact I'm pretty sure there are no other AC EVSE sockets in use at public charge points in the UK now.

 

Edited by JSHarris
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Just a quick question as I know nothing about EV's and their charging systems.

If you park in a public car park and plug in your EV using your own lead, is it possible for the local low lifes to disconnect it (for fun) / pinch the lead etc or are they somehow locked in to both the vehicle and the charge point?

 

 

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10 minutes ago, RichS said:

Just a quick question as I know nothing about EV's and their charging systems.

If you park in a public car park and plug in your EV using your own lead, is it possible for the local low lifes to disconnect it (for fun) / pinch the lead etc or are they somehow locked in to both the vehicle and the charge point?

 

 

 

The leads lock both ends.  The charge point end, which has a larger IEC62196-2 connector, usually locks under a flap on the charge point, with just the cable coming out.  The car end, either another IEC62196-2 connector, or more commonly a J1772 connector, is lockable, with a release latch that can be locked and so made secure.  Someone could cut the thing off with bolt croppers, but the latch is secure enough to prevent pranksters just pulling the plug out.  The latch is also the signalling device to turn the charge point off mid-charge.  Pushing the connector release latch down (after unlocking it if it's been locked) sends a signal to the charge point to immediately operate the double pole contactor and turn off the power.  This is so that the connector is always unpowered when it's plugged in or out.

Edited by JSHarris
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Just for some context:

 

IEC 62196

https://en.wikipedia.org/wiki/IEC_62196

 

J1772

https://en.wikipedia.org/wiki/SAE_J1772

 

CHAdeMO

https://en.wikipedia.org/wiki/CHAdeMO

 

I am not a fan of EV's from a practical point of view, plug in hybrids are a much better solution.

 

As an aside, a Tesla parked outside where I work got a parking 'bump', the kind of thing I would not even bother about (annoying as it would have been).

Apparently the repair bill was several thousand pounds.  Way out of proportion to the damage.

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  • 2 months later...

Beat them to it! 

 

My charge point has been using the radio signal that is used to transmit the excess PV generation data to the Sunamp PV to modulate the mark-space ratio of the 1 kHz pilot signal that is sent to the car to tell it what the capacity of the charger is.  This allows the car to be charged at a rate determined by the available excess PV, but there is a fundamental flaw, that cannot be overcome with the current car interface standard.

 

That flaw is that any pilot signal that indicates that there is less than 6 A available is invalid - the standard does not allow cars to charge at a current that is less than 6 A.  This means that you cannot charge the car below 6 A, as the car charger just turns off if you try to (this applies to all AC charged cars).  So, the charge point has to just turn the pilot off when the excess current available drop below 6 A, then has to pause for around 30 seconds, to allow the car charger to gracefully shut down, and then when the excess current exceeds 6 A the charge point can turn on again, but in practice it makes sense to monitor the excess for a few minutes, to try and establish how likely it is that a useful level of excess power will be sustained.  Only then does the charge point send out the pilot signal at the actual excess current, as long as it's still over 6 A.

 

Above 6 A modulation is easy, just change the mark-space ratio of the pilot and the car will, if it can, try and draw current up to the new set limit.  It's not perfect, as the car charger lags well behind the changes in the available power signal, but it does sort of work.

 

A quick read shows that Zappi have done pretty much exactly the same as I have.  FWIW, the cost of all the parts in my unit, including the radio data link, came to a bit over £100, at retail prices.  Most of the cost is the £60 for the connector that plugs into the car.................

Edited by JSHarris
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Yes, they mention the 6 amp issue somewhere on the website I think.

 

7 minutes ago, JSHarris said:

FWIW, the cost of all the parts in my unit, including the radio data link, came to a bit over £100, at retail prices.  Most of the cost is the £60 for the connector that plugs into the car.................

 

Fair enough, but you aren't trying to run a business off the back of your unit! 

 

Also, this unit will have a government subsidy associated with it for many installations. We all know what impact that has on the price of such things.

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2 hours ago, SteamyTea said:

Publish your design, stop others claiming they have rights over it.

 

I could do, in fact a part of it is already published, back from when I first designed a DIY charge point, and even back then it had a modulation input that allowed the available current pilot signal to be changed on the fly, as I was thinking ahead to adding the excess PV firmware (and it is just firmware, there's no change to the hardware, just a wireless serial data link plugged in to the board).

 

I don't want to make money from it though, so I'm happy enough for anyone to just copy what I've done if they wish.

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39 minutes ago, Barney12 said:

When I looked into this I found that subsidised installs are only available if you can prove ownership/keeper of a EV.

So if you don't yet have one you'll have to buy a unit and get your sparky to install.

 

Link to Rules

 

 

 

 

 

In addition, you have to agree to your usage data being collected and sent by a mobile data link to the installation company usually.  In my case I had a site survey for a "free" installation and the company doing it refused on the grounds that there was no mobile signal available for them to use for data collection.................

 

This was the reason I decided to design and build my own charge points, as I hadn't realised that the grant-funded installers were being given the right to remotely collect usage data, a bit like smart meters.

Edited by JSHarris
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4 hours ago, JSHarris said:

I don't want to make money from it though, so I'm happy enough for anyone to just copy what I've done if they wish.

 

I finally bit the bullet and got an Outlander PHEV. Where would I find your schematics, pretty-please Mr. @JSHarris, sir?

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I have several versions, but the simplest one would be the easiest, as it doesn't rely on the energy measurement system that I have built-in to our supply point (in essence, I have a system that measures the true energy being imported/exported at our external meter box and transmits that data for use by the hot water system and the more sophisticated charge point).

 

I'll post more info later.

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Here’s some more info on EVSEs, a schematic and generic parts list for my basic 15A/30A version (max current can be changed in firmware – the components are all rated for 30 A).

 

First you need a 32 A capable Type 1 plug: https://evconnectors.com/electric-vehicle-chargers-and-accessories/j1772-32-amp-plug-and-cable-ds1-ev32p-nc, unless you are only looking to install a 15 A EVSE, in which case you could look at getting a 16 A plug: https://evconnectors.com/electric-vehicle-chargers-and-accessories/j1772-16-amp-plug-and-cable-ds1-ev16p-nc

 

You can opt to buy the plug and a special 5 core cable, from the same links, but the cable is a bit expensive and you only actually need 4 cores (I’ve never understood why they run both pilots up the cable, as one is either unused or cut off and terminated at the EVSE plug end, if you go for a cable with a plug on both ends).

 

It’s worth making a decision now as to whether you wish to use public charge points, as you can save some money buy making your home charge cable fir both your home EVSE and a public charge point.  This costs more for connectors, but there is an overall saving.  A 5m cable will be fine for all public charge points that use an IEC62196-2 socket.

 

I’ll assume for the moment that you just want a 15 A or 30 A home EVSE with a tethered lead.  If you want to make up your own lead and connector, then 4 core H07RN-F cable is ideal, as it’s very tough and remains flexible in very cold weather.  For a 15 A EVSE you can use 4 core 2.5mm², for a 30 A EVSE you need to go up to 4mm² cable.  As a guide, this link shows prices from Quickbit, who are generally fairly competitive: https://quickbit.co.uk/cable/cable-h07rn-f-cable/h07rn-f-cable-4-core

 

Terminating the cable inside the Type 1 connector ideally needs the proper crimp tool, but it is possible to solder the cables to the buckets in the pins with care, and there’s plenty of strain relief, so solder doesn’t present a reliability issue.  If you don’t have a big soldering iron (the pins are around 6mm in diameter and do need a powerful iron), or a crimping tool, then it may well be better to just bite the bullet and buy a Type 1 plug with a cable already attached.

 

You will need a waterproof consumer unit type box to fit everything into.  I use Italian made boxes that have room for the circuitry, and space to take an IEC62196-2 socket on the front, if you want to go down that option.  These are on Ebay: http://www.ebay.co.uk/itm/IP65-MCB-RCD-Enclosure-Caravan-Hook-Up-Distributiobn-enclosure-adaptable-box-/251948088117?hash=item3aa946bb35:g:NpAAAOSwd4tUCdfa from 247 Supply, and have enough room to take a 12V power supply, a 32 A DP RCBO, and the circuitry.

The relay is mounted next to the PCB in the blank area of the box at the bottom.  You can either fit a cable gland at the base of the box to take the trailing lead, or you can just fit an IEC62196-2 socket on the front if you wish to make an EVSE that works like a public charge point, with no tethered lead.  There a pros and cons for each option, and I’ve built one of each, at opposite ends of the drive.  99% of the time I use the one with the tethered lead, as it’s quicker to uncoil and plug in.

 

Rapid electronics can supply all the components.  The relays I used were Finder 66.82.012.0000 that are rated at 30 A at 240 V, with a 12 V coil.  They are easy to fix down with screws.  I used an alloy plate cut to fit the back of the box and mounted the relay and circuit board on that.  The power supply I used was a Meanwell 12V DIN rail mount one, that has some spare capacity (one on mine also runs a wireless CCTV camera).  The model is their DR-15-12, which has the stepped top needed to fit inside a consumer unit type box.  The LEDs can be fitted in holes drilled in the spare spacers to the side of the RCBO and power supply, so they can be seen under the clear cover.

The code for the microcontroller needs to be programmed in via the serial port connector at the lower right of the board, and is tweaked depending on whether you want a 15 A or 30 A EVSE.

 

The same basic circuit is used for the variable supply unit, but I feed in serial data from a radio link to the unused input port, C.3, so the PCB is slightly different, with that pin broken out, along with +5V and 0V for the serial data radio module.  The firmware is also a lot different, as it constantly polls the receiver to get the current state of excess PV generation (if there is any) and adjusts the mark-space ratio accordingly.

 

I can post the code for the basic EVSE later if you feel up to making one, and can easily make a PCB for you and programme the chip.  If not, then there are some good kits around at not far off the same price, that don’t need so much DIY.  This is one option: http://evbitz.uk/EVBitz.uk/EVSE_Kit_-_Type_1.html  that uses the Viridian EVSE module, that has all the control stuff and contactor already built in.  These kits will fit into the enclosure I used, and you can choose to just buy the Viridian EVSE controller (http://evbitz.uk/EVBitz.uk/Viridian_EPC.html) and the Type 1 plug and buy your own cable and box.

 

 

This is the schematic:

 

59e7a2ac2ef24_SimpleEVSESchematic.thumb.jpg.cae5fa11aca8e45f29cbfe2efefb0e9f.jpg

 

And this is the PCB layout:

 

59e7a2a6f2d21_SimpleEVSEPCB.thumb.jpg.e30c6ea48036721d49ffdfc48edf5ac3.jpg

Edited by JSHarris
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  • 3 months later...

Planning to add a EV charge point to our barn to holiday cottage conversion, opening Summer 2018.

 

Has a EV charge point style won out yet or are there still multiple options?  

 

Or is it still best to just get the electrician to plumb in a big fat (unconnected) cable to a waterproof outside box and wait a bit longer?

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3 hours ago, readiescards said:

Planning to add a EV charge point to our barn to holiday cottage conversion, opening Summer 2018.

 

Has a EV charge point style won out yet or are there still multiple options?  

 

Or is it still best to just get the electrician to plumb in a big fat (unconnected) cable to a waterproof outside box and wait a bit longer?

 

 

Best bet is to fit a "7kW" unit (in reality a 32 A unit, that may or may not deliver 7 kW at any given time) that has an IEC 62196 socket on the front.  Every EV that carries a charging lead for the non-fixed lead public charging points will be able to use this.  A lot of EVs don't come with this lead, it's an optional extra, but everyone I know with an EV carries on anyway.

 

If you wanted to save the cost of buying an EVSE now, there no reason why you couldn't just run a cable to a sealed box.  None of the AC charge systems commonly used allow more than 32 A per phase, but if you wanted to future proof you could always put the cable in a duct so that it can be swapped if need be if things change.  My personal view is that I'm not convinced that many people really need anything bigger than a 32 A EVSE, unless they are thinking of getting something like a Tesla and need to be able to recharge at home quickly.  That brings a whole host of other problems, though, like reinforcing the mains supply, so probably isn't a realistic option.

 

Also worth noting that a fair few EV suppliers offer a free EVSE installation if you buy a new car.  Might make the option of just running the cable to a box a more sensible one for you right now.

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On 18/10/2017 at 13:01, richi said:

 

I finally bit the bullet and got an Outlander PHEV. Where would I find your schematics, pretty-please Mr. @JSHarris, sir?

 

HOw are you finding this?

 

The secondhand prices of the early ... 2014 ... ones are beginning to look attractive.

 

F

Edited by Ferdinand
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