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To me, 220 sounds 20 like lower than 240. I have a hunch that this might be a common perception.

Really?

I have all sorts of electronics that say everything from 208V - 240V that all go in the wall, so I think all those numbers are probably close to each other in whatever a volt is.

I think if I'm worried about a limit of some kind, being within 5% of that limit seems like I might as well be over-limit if the commonly seen distribution I see in my house is greater than 15%

I have a lot of electronics that accept 100-240v doesn’t mean I think they’re close together, just that they have compensating mechanisms to handle such voltages.

The margins are generally lower for higher power devices because the electronics are more expensive. Thankfully these electronics in general are becoming cheaper which is one reason why they’re ending up in the hands of people inexperienced with them.

Also try to tell someone they need an extra 30% in margin and often they'll think they’re being upsold.

> I have a lot of electronics that accept 100-240v doesn’t mean I think they’re close together, just that they have compensating mechanisms to handle such voltages.

I bet you also have a lot of electronics that don't though, and those that do probably say so.

My kitchen mixers, dishwasher, washing machine, driers, rice cooker, refrigerators, sauna, and pool pump aren't that tolerant by a long shot. I've got a few computers with a switch on the back to choose between 220v and 110v.

Plugging something that takes 110v into my house breaks the thing, so I've learned to check.

But I don't have anything that's 208v that can't go into the house. So I think whatever the situation is with volts, within 15% is "basically the same", so coming within 15% of the rated limit, is probably just like exceeding the limit by 15%.

And so this is why I would not expect something at 146V to be under the safety limit of 150V.

> Also try to tell someone they need an extra 30% in margin and often they'll think they’re being upsold.

Where do you get 30%?

You’re listing things that are high powered and or old. Modern PSUs don’t have that switch. While it’s in the early stages I expect more white goods to switch to BLDC motors which will likely use voltage transformers that’ll support the 110-240v.

People generally are not lugging white goods internationally, the average persons experience with different voltages is for laptop and phone chargers when they travel.

But for the matter at hand, the margin mentioned is needed on the solar systems, this is where the inverters can get expensive, which is why it can look like an unnecessary upsell to people who’ve never blown a device before.

> You’re listing things that are high powered and or old.

Sure. I have high-powered and old things, and I bet you've seen stuff like that too.

I'm explaining why I, as a non-expert, would not put 146V into something that says it can't take more than 150V.

> People generally are not lugging white goods internationally

Travel doesn't enter into it; My appliances came from Europe, they're just labelled a bunch of different voltages, so I think voltages within that range are roughly equivalent.

Furthermore, British have such a very special relationship with tea, such it would be entirely understandable that a Brit would take their kettle with them and often become quite annoyed that they cannot get an adapter to use it when holidaying amongst the yanks.

Not sure what I expected from someone who thinks 208V and 240V are close together from some labels they saw on some devices.

US appliances using single-phase power work between 208V and 240V so they work on both residential and commercial electrical systems.

Line-to-line voltage on a three-phase 208V system is 208V, line-to-line on 240V single-phase system is 240V.

Most commercial lighting products are rated for 120V-277V so they work on both residential and commercial (480/277V line-to-neutral single phase voltage is 277V)

> Adding "resilience" usually adds to the per-unit cost.

In this case, the cost is much less than a dollar (say, a varistor that blows the existing fuse) and it prevents a catastrophic failure.

But they want you to have to buy another one.

Why does this kind of comment get downvoted that pinpoints the actual motivation? We just pretend that planned obsolescence is history.

At least in parent's case, probably because the vast majority of their comments are black-and-white hot takes that are always downvoted regardless. And they basically never respond when asked for any sources.

Yeah bad faith commenter then

Voting based on ad hominem is against HN guidelines.

I’m sorry who did you mean to say this to? Not sure this is relevant here

Because it’s an extreme claim backed up with no evidence. Hanlon’s razor applies here.

Also see Hitchens' razor and Russel's teapot.

They're just being cheap. If you're going to let customers plug panels directly into your box you should have overvoltage protection. It's that simple.

> Making a web page to educate future customers seems like a really good idea

I don't think this is an official website of ecoflow.

Other than that I agree. I don't think asking for a bit of knowledge from the customers is a bad thing. A warning in the manual about safety factors should be enough.

> Idk. I don't have a PHD, but 220V sounds like 240V to me. I wouldn't do this.

220[Vrms] * 1.414 = 311[Vp-p] btw. HOW!?

AC wiggles and wobbles.

So the issue is that 220V is nominal in China, 230V nominal in UE and 240V is UK/part of Australia. So if anyone is preparing product for global market (as most are doing now) more likely then not will support all of this voltages. Thus is kind of normal (but wrong) to assume 220V sounds like 240V.

When the voltage was unified in UE, the nominal value was set to the median of 230 V, but its tolerance was raised from 10% to 15%, so that the new maximum peak value of 230V + 15% will match the old value of 240 V + 10%.

So now for all 220/230/240 V standards you have the same maximum voltage value that is used for electrical designs (about 265 V effective), so they are equivalent, regardless of the name.

True, however there is also old equipment. For example I have heard that light bulbs designed for 220V will last for noticeably shorter period of time ar 230V nominal circuit. That is why it is worth to check supported voltage. But you are right - newer equipment will suport all voltages.

Many charguers are now 100-240V, 50-60Hz, that is close to pluggable anywhere on Earth. (I burned one or two a long time ago, when I forgot to check and used a 120V transformed here with 220V)

Same thing happened to PC PSUs. I don't think there is a recent unit that still has the self-destruct voltage selector switch which pops them if you are in 230V land (and the switch is set to the smaller setting).

Besides the ratio between the peak and effective value, you must also account for the standard tolerance of the nominal value.

The actual maximum peak voltage for the European mains, is 230 V * 1.15 * sqrt(2), because of a 15% tolerance. That is about 375 V. With a small safety margin, the minimum voltage rating for components connected to 230 V a.k.a. 220 V is of 400 volt.

Makes me wonder if that was how EV DCFC quickly settled with 400VDC. The voltage makes sense if it was somehow known that engineers has intuitions with safe designs for 400Vp-p systems.

I would be wary of relating any DC constraints to AC constraints and behaviour.