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DIY Home EV Charger

jamesfotherby.com

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Re: DIY Home EV Charger

#121

Post by gambiting »

tw04 wrote: post #27
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.

>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 the UK law on this does not.

Re: DIY Home EV Charger

#122

Post by tverbeure »

throitallaway wrote: post #89
NotSammyHagar wrote: post #84

Earlier quoted context omitted.

The evse (misnamed charger here) needs to reduce the amperage based on what the car side wants. So it does more than just pass mains voltage.

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 similar that way if they wanted to...

Re: DIY Home EV Charger

#123

Post by michaelt »

mrb wrote: post #94

"It costs about £900 in the UK to have an EV charger installed by an electrician" £900 is $1140. In southern California, it cost me $750 for top notch work and hardware, including: $400 to have an electrician install a 240V 50A outdoor outlet (NEMA 14-50), plus $350 for a good quality level 2 40A EVSE (this one: https://www.amazon.com/dp/B082LMVSLY ) that I installed myself as it simply plugs in the outlet and it's j…

> I would love to see a breakdown of that £900... that seems really high.

The £900 will include: supply of a 7kW EVSE; adding a new circuit to your consumer unit/fuse box; running a few tens of meters of fairly expensive cable (6mm SWA suitable for outdoor and underground use) in a careful, tidy way; adding an extra ground point, if needed; an electrical safety test with a special tester; and issuing a certificate (which is mandatory for this type of installation). It'll take the electrician about a day.

People in the UK pay a fairly hefty premium as we don't have as many qualified installers as we probably ought to.

Of course, standard British sockets already supply 3kW - so the cheaper option is just to get an outdoor socket installed on an existing ring main. This is substantially quicker to install in most cases.

Re: DIY Home EV Charger

#124

Post by djaychela »

rsync wrote: post #97
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…

"... would nullify my homeowners insurance ..." It almost certainly wouldn't. Generally speaking, in the United States, homeowners insurance "covers stupid". DIY electrical wiring, and the like, would be covered unless something was intentionally or maliciously negligent. If you miswire a three-way lightswitch (in good faith) and (somehow) burn your house down, that is generally covered.

I'm not sure that's true in the UK. The law changed a few years ago limiting the kind of changes you can make to your home wiring, and you have to have a certificate for new circuit installations or significant modifications. I would not want to be the test case for finding out if this did invalidate your home insurance.

Re: DIY Home EV Charger

#125

Post by bigfudge »

myself248 wrote: post #116
MostlyStable wrote: post #6

Earlier quoted context omitted.

I would have liked to see a cost breakdown. If it's significantly cheaper than OpenEVSE (somewhwere between $500-$600 depending on which kit you get), then maybe some people would be willing to take the risk (it seems like there are some safety concerns with his design that I don't feel qualified to adjudicate). But without some kind of a cost difference, I'd probably stick with something like OpenEVS, which seems to…

OpenEVSE can be a codebase or a kit. If you want to source all your own parts, or maybe reuse significant parts of a non-open EVSE and just drop the processor into it or whatever, then it can be very cheap indeed. If you buy their branded kit, then full price applies. When OpenEVSE was new, I built one on perfboard, actually a very compact modular stack of perfboards, one layer per subsystem. Handed it off to my soft…

What I don’t understand is what the motivation for manufacturers to not just install the open software is… are they trying to harvest charge time data or something? It seems like it would be easier to change any logos in software but leave the rest as is. Non tech buyers wouldn’t know or care… and nerds would buy it in droves. This goes for a lot of the low end network gear too. Are they really adding much value in software?

Re: DIY Home EV Charger

#126

Post by Dylan16807 »

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?

It's funny that people don't want to call it a charger specifically because it doesn't do the AC-DC conversion, and your example of a thing people call a charger is an AC-DC converter.

And depending on the sophistication of the phone, that converter outside the phone might be doing most of the work.

Re: DIY Home EV Charger

#127

Post by Dylan16807 »

KennyBlanken wrote: post #47
myself248 wrote: post #3

Save you a click: It's an EVSE, not a charger. Looks very similar to OpenEVSE but he wrote his own code. Nice clean build. Not sure why the extra work instead of just downloading OpenEVSE.

Everyone calls them chargers. If you said "do you like the EVSE you have?" or "do you know where the nearest EVSE is?" most people would stare at you with a blank expression.

> If you said "do you like the EVSE you have?" or "do you know where the nearest EVSE is?" most people would stare at you with a blank expression.

Because you'd need to use a word like "plug" or something, not because of whether it's "charger" specifically.

Re: DIY Home EV Charger

#128

Post by bigfudge »

tw04 wrote: post #95
clnq wrote: post #34

Earlier quoted context omitted.

You’re responding to a statement you straw-manned. The comment you’re responding implies a slippery slope, not an equivalence between DIY safety and letting kids be outside.

What? Are you op's alt-account, or did you not bother to read his response? I straw-manned nothing. He compared making your own home-charger to letting your kids play outside, not me. I simply pointed out that comparing the two was ridiculous. The fact you'd accuse me of straw-manning when I was doing literally the opposite is somewhere between hilarious and offensive.

FWIW I read it as a straw man too, and the original as a slippery slope argument rather than an equivalence. Communicating in short bits of text is hard.

Re: DIY Home EV Charger

#129

Post by bigfudge »

mindslight wrote: post #66
reanimus wrote: post #46

Earlier quoted context omitted.

Homeowner's insurance assumes you're doing your due diligence to not do things that unnecessarily destroy your home. Negligence is specifically not covered when it's something that you should have reasonably been able to prevent. There's a difference between a panic-induced response that makes an accidental fire worse and you making the explicit decision to install something unsafe.

I see the distinction you're making with my specific example, but I'm aware of no such distinction for the policies I've had. Are you referencing any concrete laws or contractual terms? Also then, a different example: You plug in a non-NRTL-tested appliance from Amazon, and it burns down your house. Clearly outside the bounds of what is prudent, but also something many people commonly do. You're telling me that insur…

Ianal but the law often seems to work on the basis of terms like reasonable or expected. Buying junk electronics from Amazon is so common and risks so little publicised that it doesn’t seem reasonable to exclude them. Building a diy power supply is very uncommon and almost certainly requires knowledge to do so that would also tell you it’s a dumb idea.

As an aside- do cheap electronics actually burn a lot of houses down, or is that scare mongering? I half remember reading that it was large white goods like dishwashers and washing machines that actually started most fires, and they are not typically bought on Amazon or only on price.

Re: DIY Home EV Charger

#130

Post by dbrgn »

mrb wrote: post #94

"It costs about £900 in the UK to have an EV charger installed by an electrician" £900 is $1140. In southern California, it cost me $750 for top notch work and hardware, including: $400 to have an electrician install a 240V 50A outdoor outlet (NEMA 14-50), plus $350 for a good quality level 2 40A EVSE (this one: https://www.amazon.com/dp/B082LMVSLY ) that I installed myself as it simply plugs in the outlet and it's j…

Another recent example: I'm in Switzerland. I paid 550 CHF (630$) this summer for a "go-e Gemini" charger. I screwed it to the wall and ran a roughly 15m 3-phase 16A cable to the main fuse box (maybe around 50 CHF for cable and installation tubes), where an electrician connected it properly for 108 CHF (124$) and added an appropriate RCD for 116 CHF (133$). All in all, it cost me around 800-900 CHF (900-1000$).

Without doing some of the installation work myself, the electrician would have cost me several hundred CHF more.

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