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We need a lot more electricians

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Re: We need a lot more electricians

#361

Earlier quoted context omitted.

Right, don't go off code for having to do a big upgrade like this. I legit hit 100A several times a month. Have hit over 150A. Easy way for me to draw 100A at once: 40A: EV charging 32A: Electric Oven warming up at max 24A: Electric Dryer 40A: HotTub jets on 40A: AC ON Max Unlikely all of those are on full max, but it's pretty easy to imagine getting past 100A before we even touch things like lights and computers. EV…

Do Americans quote large appliance current at 220V or 110V equivalent? From the EV it seems the former, but in that case I'm horrified at how power-hungry your appliances are. A typical new oven sold in Europe is 3.6kW, 16A @ 230V. A new tumble drier is 600W, so about 2.5A at 230V. There's such a range of hot tub and AC sizes I can't compare these.

My small, or at least unremarkable, oven is 4.8kW, also 230V. It's from about 2006, iirc.

Electric tumble dryer is 5.6kW at 230V. It's from 2017. Maybe yours is gas, and 600W is the motor?

I have a smallish 1900sqft 1950s house with average or smaller appliances.

I love doing appliance comparison with European houses, though.

Re: We need a lot more electricians

#362

Earlier quoted context omitted.

Required to sheath ground in green? What on earth for? That makes ground less effective since you want any incidental contact with ground to ground the object touching it.

Because without a common language for what color wires carry load a simple oversight can be fatal.

Except a bare wire is always a ground.

Re: We need a lot more electricians

#363
post #248

Earlier quoted context omitted.

Right, don't go off code for having to do a big upgrade like this. I legit hit 100A several times a month. Have hit over 150A. Easy way for me to draw 100A at once: 40A: EV charging 32A: Electric Oven warming up at max 24A: Electric Dryer 40A: HotTub jets on 40A: AC ON Max Unlikely all of those are on full max, but it's pretty easy to imagine getting past 100A before we even touch things like lights and computers. EV…

And if you only have a 200A service, your service drop is likely only 2 or 1/0.

Most 200A services around me are 4/0 Aluminum

2/0 copper would work but would cost more, so likely not used.

Re: We need a lot more electricians

#364
post #311

Earlier quoted context omitted.

> electric tools (like chainsaws) The amount of electricity shifting all gas powered tools like chainsaws and lawn mowers to electricity is less than a drop in the bucket compared to the other needs. Changing all my tools from gas to battery increased my electric bill in the peak growing season by like 2.5kWh/month, compared to a usual usage of ~2,000kWh/mo. Its also a pretty easy to time shift demand and doesn't nee…

Now your nit picking on one thing on the list. EVs, home heat/AC, and stoves are all substantial (depending on how much you use the stove). When looked at on a macro scale there is an impact.

> When looked at on a macro scale there is an impact.

At a macro level, for the chainsaws and tools that's as if each household left a single 4W LED lightbulb turned on all the time. If that's enough to have to seriously re-think the grid we're already massively doomed. I better go and talk to the power company to get approval before I plug in another lamp at home!

If you don't want someone nitpicking the equivalent of a 4W lightbulb on your list, don't include the equivalent of a 4W lightbulb on your list. It doesn't belong on a list comparing it with things like adding heat pumps, EVs, all electric home appliances like electric ranges and what not. All of those use literally hundreds of times more electricity, some during times which are hard to load shift or spread the load out over several hours.

Even then, when well time-shifted and people aren't excessive in their load, adding an EV to a household's energy usage really doesn't rock the boat nearly as much as you'd think.

The average car puts what, 14,000mi on it a year? Lots of EVs can get ~3.5mi/kWh, so that's 4,000kWh an average car would put on the grid over a year. So ~333kWh/mo. For a home using ~2,000kWh/mo before an EV, that's adding ~17% to their energy usage which can often easily be shifted and spread out to what is usually the lowest demand part of the day (late, late evening/early early morning). Its not like its doubling their usage to add an EV.

A large chunk of the time when my EV charges the wholesale electricity rates in my area are negative. Often during the way off-peak hours the grid is nowhere near max utilization. True, this varies from location to location, but no grid is operating at like 95% generating and delivery capacity all the time.

I do agree there will be some big changes that'll need to happen with electrification. Some places will have bigger changes than others, such as places that didn't even have AC before moving to heat pumps. But when it comes to places that already had to deal with a good amount of AC usage, switching from some other form of heating to heat pumps isn't really changing the peak usage that much. Its just keeping that high usage year round versus only in the summer.

But honestly if everyone on my street added an EV to their home the power company would not need to make a single change. The grid is already planned to handle all these homes with their AC running in the peak summer days while running an electric stove and the rest of their home appliances on normal schedules during waking hours, having a 28A or 32A circuit running at the coolest hours of the day when everyone is sleeping (practically nobody is doing laundry at 3am while running the oven and stove) isn't going to upend the grid. I realize not everyone on the planet lives on my street, but my street isn't some fanciful magical place that exists only in dreams.

Re: We need a lot more electricians

#365
post #101

Earlier quoted context omitted.

There is a good chance that if you installed GFCI in some old house it would just... trip due to shitty wiring. But yeah, the law should probably have exception for installing safety devices, it's better to have some than zero because someone can't afford it.

>There is a good chance that if you installed GFCI in some old house it would just... trip due to shitty wiring. No, that's not true! A GFCI measures the current going in and the current going out and if they are not equal it trips.

I had a GFCI installed in my 1930s built house the other week

The circuit repeatedly tripped, so the electrician uninstalled it. To install the GFCI he would need to spend 1-2 days splitting circuits to find the leak(s) so instead of ~$40 + 1 hours labour it's potentially thousands of dollars

Re: We need a lot more electricians

#366

Earlier quoted context omitted.

I have twice lost a fridge full of food due to spurious GFCI trips, once when I was a recent graduate and it was a painful experience financially. I now make sure my fridge/freezer is NOT on a GFCI. I'll take my chances of getting a 120VAC shock from my fridge [which is attention-getting, but very unlikely to be injurious].

Also funny how fridges are required to have their own circuit, but newer fridges are increasingly vfd/inverter drive, and don’t have surge power draws anymore. They use a few hundred watts continuously and that’s it. I’d be more quickly to find out my fridge died if the lights in the kitchen stopped working. Not sure why fridges don’t just have a battery-powered alarm that goes off when the temperature gets too high…

What kind of fridge do you have that draws several hundred watts continuously? I haven’t tested my fridge, but I have a very large chest freezer that never draws more than ~35W. Surely a fridge can’t be 10x worse than that.

Re: We need a lot more electricians

#367
post #21

Earlier quoted context omitted.

Did you upgrade your wiring? Your old breakers were the size they were for a reason.

Even with the same size breakers you have to be careful. Many circuits in the US are wired using a shared neutral. These circuits must not share the same phase and when rewiring an entire panel this seems like it'd be an easy mistake to make.

Multiwire branch circuits must be wired with tied breakers. If the person rewiring doesn't understand that this must be duplicated in the new panel, they definitely has no business upgrading their own panel.

Re: We need a lot more electricians

#368

Earlier quoted context omitted.

> Even after the replacement was complete the electrician had to come back and redo the wiring connections because the inspector said the PVC joint at the top of the box had to be metal instead. Right. There must be a reliable metallic path to ground. This is a big problem with PVC pipe retrofits. In older houses, plumbing and conduit are metal and good grounds, and grounding to plumbing used to be permitted. Once PV…

> ... and grounding to plumbing used to be permitted Do you have a citation for this? I was under the impression that using plumbing as equipment ground was never allowed, but that conductive plumbing has required to be bonded to ground for some time. I was further under the impression that by code, plumbing repairs couldn't leave behind unbonded sections of conductive plumbing.

I assisted with a few residential electrical-service upgrades last year (in California). ...If the plumbing pipe could be used as one of two paths to ground (i.e. conductive all the way), it was. Otherwise two grounding stakes were installed instead of one.

> by code, plumbing repairs couldn't leave behind unbonded sections of conductive plumbing

I assume that's correct, but I think shady / lazy / amateur contractors can assume the inspector won't check work in the crawl space.

Re: We need a lot more electricians

#369
post #34

Earlier quoted context omitted.

I'd never heard of a 400 A service until just this discussion (it's common to have 100 A - 200 A), but it's important to keep in mind the voltage differences and that effect on total power: UK: 100 A x 230 V = 23,00 W US: 200 A x 120 V = 24,00 W Edit: I am wrong in my understanding of US power distribution. It's 200 A per leg, which the US has two of. But it seems like the UK may or may not have 380 3 Phase, so the n…

> but it's important to keep in mind the voltage differences and that effect on total power: > UK: 100 A x 230 V = 23,00 W > US: 200 A x 120 V = 24,00 W That's incorrect. The service drop in the US is 220V. It gets stepped down at the main load center to 120V for most of the regular circuits. So it's more like 48000W service in US houses.

> The service drop in the US is 220V.

240V. Since we're throwing around numbers, let's be accurate. This is a pet peeve of mine. We've been standardized at 240V since 1967, and it was higher than 220V years before that.

Re: We need a lot more electricians

#370

Earlier quoted context omitted.

Do Americans quote large appliance current at 220V or 110V equivalent? From the EV it seems the former, but in that case I'm horrified at how power-hungry your appliances are. A typical new oven sold in Europe is 3.6kW, 16A @ 230V. A new tumble drier is 600W, so about 2.5A at 230V. There's such a range of hot tub and AC sizes I can't compare these.

2 4 0V circuits are simply both legs of the 1 2 0V split phase connected together, so the amperage is measured at 120V. The circuit breakers for 120V and 240V circuits are the same, except 240V circuits use two breakers with the handles tied together[1]. Electric resistive heaters like ovens and clothes dryers are always perfectly efficient, so I'm not sure how you even thought it would be possible to have an ineffic…

> I'm not sure how you even thought it would be possible to have an inefficient heater

They're inefficient relative to a 250-500% efficient heat pump.

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