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DIY Home EV Charger

jamesfotherby.com

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Re: DIY Home EV Charger

#141

Post by elihu »

gambiting wrote: post #120
elihu wrote: post #61

Earlier quoted context omitted.

And yet the technical people need accurate names to call things so they can communicate without ambiguity. I think "charging station" is the least confusing term for the fixed infrastructure part. If regular people call those "chargers" in non-technical conversation, then I'm not going to lose sleep over it.

The thing that you use to provide your phone with electricity - do you call it an AC-DC converter, or do you call it a charger like nearly everyone on earth, even though the charger part is actually inside your phone?

I call it a USB cable.

Re: DIY Home EV Charger

#142

Post by urtie »

I've run something similar for 5 years, using https://www.smartevse.nl/ as the brains. The main advantages over commercial EVSE's in my case were that I could loadbalance charging the car with the electricity demands of the house, and that I could have the EVSE itself inside, so that there's no 240V current on any circuit from the breaker box indoors towards the car when there's no car present.

I do intend to add a second sometime, so that I can put the EVSE in my home automation UI as well; the version 2 of smartevse that I use does not have a network connection, but it can be connected to be controlled by a version 3 that does.

Re: DIY Home EV Charger

#143

Post by nsteel »

michaelt wrote: post #139
Symbiote wrote: post #133

Earlier quoted context omitted.

> the cheaper option is just to get an outdoor socket installed on an existing ring main From my searching, this doesn't meet the current regulations of the socket is intended for EV use. The costs to make it compliant bring it up to the better options anyway.

It goes without saying that you've got to have a 'granny cable' with appropriate protection - but AFAIK every EV comes with one of those. And of course, you'd fit a socket like [1] which is waterproof even when in use, and has a built-in RCD if your consumer unit doesn't have one. It's common sense when using electricity outside. And your installer will want to make sure the circuit has enough capacity to avoid nuisa…

> but AFAIK every EV comes with one of those.

No, not any more.

Re: DIY Home EV Charger

#144

Post by nsteel »

gambiting wrote: post #118
prmoustache wrote: post #117

Earlier quoted context omitted.

Also. £900 is negligible and pocket change compared to the price of an EV, even in the second hand market.

No one looks at it this way, because extremely few people buy cars with cash. Majority of buyers buy a car on finance - and compared to the monthly £500 a car might cost you, £900 is not insignificant, that's nearly two car payments, and also I have no idea how wealthy you'd have to be to call £900 "pocket change". We have an EV and a PHEV, I had a charger installed back when government grants were much more generous…

I used a granny charger for the first 3 weeks after getting my EV. I don't use the car that much but even so, the painfully slow charging made it a hassle. And also remember, if you want access to cheap electricity, you need to use a "real" EVSE. This DIY one can't provide access to that either.

Re: DIY Home EV Charger

#145

Post by nsteel »

gambiting wrote: post #121
tw04 wrote: post #27

Earlier quoted context omitted.

>I'm disappointed at the anti-DIY sentiments here, it's this safety obsessed mentality that got us to where kids can't walk outside by themselves any longer. Just no? That analogy is EXTREMELY strained. From his own link: A word about safety. I’m not an electrician. I’m not allowed to make alterations to my consumer unit. I let my kids play outside all the time solo and with friends without supervision. On the flip s…

>>I’m not an electrician. I’m not allowed to make alterations to my consumer unit. So two funny things about this in UK law - the law doesn't say who is allowed to work on your consumer unit, you can do it by yourself if you wish. What the law does specify is that the work has to be certified by a "competent person" but then doesn't actually narrow down what a "competent person" means. Local regulations might, but th…

But they can provide a list of them! https://www.competentperson.co.uk/

Re: DIY Home EV Charger

#146

Post by gambiting »

nsteel wrote: post #145
gambiting wrote: post #121

Earlier quoted context omitted.

>>I’m not an electrician. I’m not allowed to make alterations to my consumer unit. So two funny things about this in UK law - the law doesn't say who is allowed to work on your consumer unit, you can do it by yourself if you wish. What the law does specify is that the work has to be certified by a "competent person" but then doesn't actually narrow down what a "competent person" means. Local regulations might, but th…

But they can provide a list of them! https://www.competentperson.co.uk/

Of course - but again, the law doesn't specify that a "competent person" has to be on that list, or any list.

There was a huge debate about this couple years ago, when someone asked "can a foreign electrician certify a UK electrical installation as safe", and after very long debate the outcome was that yes, they can, because the British regulations never actually specify what they mean by "competent" and a certified electrician(even if foreign) is definitely "competent" even if not registered with any UK based authority.

Re: DIY Home EV Charger

#147

Post by gambiting »

nsteel wrote: post #144
gambiting wrote: post #118

Earlier quoted context omitted.

No one looks at it this way, because extremely few people buy cars with cash. Majority of buyers buy a car on finance - and compared to the monthly £500 a car might cost you, £900 is not insignificant, that's nearly two car payments, and also I have no idea how wealthy you'd have to be to call £900 "pocket change". We have an EV and a PHEV, I had a charger installed back when government grants were much more generous…

I used a granny charger for the first 3 weeks after getting my EV. I don't use the car that much but even so, the painfully slow charging made it a hassle. And also remember, if you want access to cheap electricity, you need to use a "real" EVSE. This DIY one can't provide access to that either.

>>And also remember, if you want access to cheap electricity, you need to use a "real" EVSE.

Why? I was on Octopus Go for a long time, I'd just set the in-car timer to charge between 00:30 and 04:30, worked fine even with a 3-pin charger. It won't work with Intelligent Octopus, but it's by no means the only way to get cheap electricity.

Not that it matters anyway, I kept a detailed log of our usage for months and concluded that GO wasn't actually saving us any money, the cheaper electricity at night didn't offset the energy used during the day, not at the idiotic prices they charged for peak usage anyway. We just switched to Octopus Tracker, I can charge my car at any point during the day and it's actually cheaper than being on GO.

Re: DIY Home EV Charger

#148

Post by SigmundA »

tverbeure wrote: post #122
throitallaway wrote: post #89

Earlier quoted context omitted.

This completely goes against my understanding of electricity. The correct amount of amps are pulled by the plugged in device, and it doesn't matter how much are available at the supply side (as long as it meets the minimum.)

Any good DC lab power supply can operate as a constant voltage source or constant current source. By default, the power supply will maintain a constant voltage at the terminals, but if the connected device starts too pull a current that's higher than the specified limit, the power supply will lower the voltage to keep the current in check. Not saying this is the case here, of course, but they could do something simil…

These are not DC power supplies, thats whats inside the car, a boost DC power supply converting 240v AC to 400v or 800v DC, thats what regulates current and voltage to the batteries.

If the AC "charger" attempted to regulate current by varying voltage the actual onboard charger would just attempt to pull more current to make up for the voltage drop and probably trip the whole thing.

There would be no point in regulating the AC current, it would make the charger very complicated and expensive replicating much of whats in the DC converter/charger in the car.

A full DC charger like at a charging station does do this because it is the actual charger bypassing the cars small internal DC charger with DC leads going directly to battery at full pack voltage.

Re: DIY Home EV Charger

#149

Post by mcbishop »

pardoned_turkey wrote: post #38
foobarian wrote: post #12

I'm disappointed at the anti-DIY sentiments here, it's this safety obsessed mentality that got us to where kids can't walk outside by themselves any longer. The box in that guy's build is outside and could probably burn to a crisp without hurting anything else. I suspect it would not hurt anything even inside a garage, other than making a lot of smoke and setting off smoke detectors.

All the no-name $6 extension cords from Amazon that we have in our homes are far more likely to burn your place down than this project. It's surprising that we have such cavalier attitudes when it comes to our own field, but so much fear and magical thinking about the power of government oversight when it comes to everything else...

Yup, I'm sure a lot of people are trickle charging their EVs with 16-gauge extension cords.

Re: DIY Home EV Charger

#150

Post by sumo89 »

michaelt wrote: post #139
Symbiote wrote: post #133

Earlier quoted context omitted.

> the cheaper option is just to get an outdoor socket installed on an existing ring main From my searching, this doesn't meet the current regulations of the socket is intended for EV use. The costs to make it compliant bring it up to the better options anyway.

It goes without saying that you've got to have a 'granny cable' with appropriate protection - but AFAIK every EV comes with one of those. And of course, you'd fit a socket like [1] which is waterproof even when in use, and has a built-in RCD if your consumer unit doesn't have one. It's common sense when using electricity outside. And your installer will want to make sure the circuit has enough capacity to avoid nuisa…

Sample of 1 but yeah we have a plug in hybrid and and waterproof socket in the storm porch, the car charges in a few hours. No desire to spend nearly 1k to charge a bit quicker
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