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DIY Home EV Charger

jamesfotherby.com

11–20 of 195 posts

Re: DIY Home EV Charger

#11
1. Two words: strain relief.

2. If it's outdoors, at least spray the electronics with Fine-L-Kote or similar to keep water vapor out.

3. Those relays look undersized for the load. Look at Grainger for similar ratings. Do not buy power relays on eBay or Alibaba. Current ratings there tend to be wildly exaggerated.

4. Er, overcurrent protection? An approved circuit breaker?

Re: DIY Home EV Charger

#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.

Re: DIY Home EV Charger

#13

This is such a bad DIY project because the costs of screwing up can be burning your house down. This is non-trivial amounts of power. If you spend the money fot an EV, buy something safe and have it professionally installed. Keep the DIY projects to something less dangerous.

Software engineers have a tendency to overestimate their own abilities, the arrogance is often on full display here for all to see.

Maybe we need a few to burn their own houses down to act as a deterrent and encourage others to stay in their lane.

Re: DIY Home EV Charger

#14
post #11

1. Two words: strain relief. 2. If it's outdoors, at least spray the electronics with Fine-L-Kote or similar to keep water vapor out. 3. Those relays look undersized for the load. Look at Grainger for similar ratings. Do not buy power relays on eBay or Alibaba. Current ratings there tend to be wildly exaggerated. 4. Er, overcurrent protection? An approved circuit breaker?

He says he installed a 50A OCPD, which is the same overcurrent protection an electrician would install and used relays from TE Connectivity (a respected brand) rated at 125% of the current the EVSE advertises as available. Both of those decisions seem perfectly sane/safe to me.

Re: DIY Home EV Charger

#15
post #11

1. Two words: strain relief. 2. If it's outdoors, at least spray the electronics with Fine-L-Kote or similar to keep water vapor out. 3. Those relays look undersized for the load. Look at Grainger for similar ratings. Do not buy power relays on eBay or Alibaba. Current ratings there tend to be wildly exaggerated. 4. Er, overcurrent protection? An approved circuit breaker?

Any Fine-L-Kote like recs that HD, Lowes carry?

Re: DIY Home EV Charger

#16

This is such a bad DIY project because the costs of screwing up can be burning your house down. This is non-trivial amounts of power. If you spend the money fot an EV, buy something safe and have it professionally installed. Keep the DIY projects to something less dangerous.

It looks like all he’s doing is switching mains voltage, so it doesn’t seem that dangerous. There isn’t much that can go wrong with the high-power side of this system.

Re: DIY Home EV Charger

#17

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.

Fairly certain most DIY electrical work is strictly verboten in the UK, where the author is located. I would think at a minimum you need approval from the council. Not too dissimilar to the permitting process in the US, but the UK is noticeably more safety-obsessed.

Re: DIY Home EV Charger

#18

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.

The leaps here are way too big.

Re: DIY Home EV Charger

#19

More like a DIY arson investigation. You might not only burn down your house, but also get in trouble with the law and not receive compensation from your property insurance company. This is a horrendous idea. Just do basically anything else DIY besides high current/voltage electronics.

Some of us on here don’t know just software engineering and nothing else

Congrats to OP on a clean project

source: electrical engineer who writes high performance software you’ve definitely have used

Re: DIY Home EV Charger

#20

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.

Fairly certain most DIY electrical work is strictly verboten in the UK, where the author is located. I would think at a minimum you need approval from the council. Not too dissimilar to the permitting process in the US, but the UK is noticeably more safety-obsessed.

Well, there's a pretty large fraction which is still fine to do full DIY. (but not EV chargers) The next level basically either requires some certification or to get the council to inspect it, but plenty of people just ignore that.
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