General > General Technical Chat

The real reason why North America uses 120v instead of 240v.

<< < (15/17) > >>

jmelson:

--- Quote from: bdunham7 on November 24, 2022, 09:22:06 pm --- Older houses, especially attics and crawlspaces, along with barns, seem to be the among the most dangerous places.

--- End quote ---
Yup, poking around inbasement ceilings and inside walls of houses with knob and tube wiring, you will find bare conductors all over the place where you least expect it!
Jon

Gyro:

--- Quote from: AVGresponding on November 26, 2022, 06:48:35 am ---Generally speaking, 240V tools are not permitted on construction sites, regardless of cable length. Using battery tools is usually a matter of convenience, but for heavier tasks, the leaded 110V stuff gets used. Better to put wear on the gearbox of the hired SDS hammer drill than my own battery one!

--- End quote ---

That really ought to be discriminated as 55-0-55V rather than 110V. In the case of accidental contact you'd only get hit with 55V, it would take holding one wire in each hand to get a 110V shock. It's almost SELV.

AVGresponding:

--- Quote from: Gyro on November 26, 2022, 11:21:49 pm ---
--- Quote from: AVGresponding on November 26, 2022, 06:48:35 am ---Generally speaking, 240V tools are not permitted on construction sites, regardless of cable length. Using battery tools is usually a matter of convenience, but for heavier tasks, the leaded 110V stuff gets used. Better to put wear on the gearbox of the hired SDS hammer drill than my own battery one!

--- End quote ---

That really ought to be discriminated as 55-0-55V rather than 110V. In the case of accidental contact you'd only get hit with 55V, it would take holding one wire in each hand to get a 110V shock. It's almost SELV.

--- End quote ---

It's easier to just refer to it as 110V, and in the cases of CPC failure, class 2 devices (many drills etc are this now) and festoon lighting (where there is no CPC) for example, that's exactly what it is.

The inclusion of a CPC would make it PELV, not SELV, and it would have to be under 50V between any two conductors to meet the criteria for either.

mfro:
Just to fire up discussion: German statistics list 32 deaths caused by electricity  in 2019, 7 of them in industry/commerce (that is: professional) environments.

US population is (roughly) four times that of Germany, UK about 20% less.
 

tom66:

--- Quote from: JPortici on November 25, 2022, 09:17:29 pm ---In italy there should still be some areas in Turin and Rome with three phase 230V, no neutral (residential utilities are connected between two phases)
however the last i heard of it is that they started converting to the current 400V 3phase + neutral

--- End quote ---

I know Belgium is similar, in rural areas.
Apparently some electric vehicles cannot charge off such 230V 3ph, they require a neutral (they will charge on the slow charger, but not on a wall box.)

Navigation

[0] Message Index

[#] Next page

[*] Previous page

There was an error while thanking
Thanking...
Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod