Question: 120 volt lighting circuit

[joulesarecool]

I'm aware that the 1987 code edition required lighting that was within a certain distance from the floor or grade (say 7'-6" for example) to be wired to a 120V source. In the 1990 edition up to the current edition, this requirement has been removed, as far as I can tell.

Is it a commonly held belief that all lighting within reach by an individual be wired for 120V for "safety" (less of a shock in case of a short) reasons, even thought it is not code required?

 

[barbeer]

I would think 410.3 (05) replaced those requirements no matter what voltage.

 

[celtic]

Is it a commonly held belief that all lighting within reach by an individual be wired for 120V for "safety" (less of a shock in case of a short) reasons, even thought it is not code required?

It is NOT a belief I subscribe to.

120v will kill you just as dead as 277v.
The fact of the matter is, there are MORE incidents at the lower voltage (120v) than at the higher voltage (277v).

250.110 may be where you got the height requirement concept:

(1) Where within 2.5 m (8 ft) vertically or 1.5 m (5 ft) horizontally of ground or grounded metal objects and subject to contact by persons
(6) Where equipment operates with any terminal at over 150 volts to ground

or perhaps Part V of 410 (410.17 et al))?

Luminaires (fixtures) and lighting equipment shall be grounded as required in Article 250 and Part V of this article.

There are some other requirements in 210.6

 

[iwire]

I think it is a wise idea to keep 277 out of reach and find that is commonly practiced in my area.

Lighting on store shelfs, displays etc will all be 120 while up at the ceiling will be 277.

I don't want to receive a shock from either 120 or 277 but if I had to make a choice.....

 

[Denis]

zap

zap

"I don't want to receive a shock from either 120 or 277 but if I had to make a choice....." 277v is my preference

 

[George Stolz]

If you're gonna go down, go down with a bang...? :-?

 

[mengelman]

I think there are more incedents of 120 killing people because 120 is accessable to more people.
I dont think I have ever seen 277 or more in a home.

 

[peter d]

Faults are much more powerful and explosive at 277 volts, another good reason to keep 277 volt lighting up high.

 

[dbuckley]

Please, forgive me for being amused; 277V is only a little bit more than 240V, and thats what all the lights I've been around for almost all my life operate from. I cant see whats especially dangerous about properly constructed 277V fittings...

 

[480sparky]

Please, forgive me for being amused; 277V is only a little bit more than 240V, and thats what all the lights I've been around for almost all my life operate from. I cant see whats especially dangerous about properly constructed 277V fittings...

240 is a phase-to-phase voltage. Get between one phase and ground, you've got 120 volts cookin' your innards. It's kind of difficult to accidently get between the phases in a ground-fault scenario. But 277 is a phase-to-ground voltage. Grab hold of one phase, and you've still got 277.

 

[Pierre C Belarge]

240 is a phase-to-phase voltage. Get between one phase and ground, you've got 120 volts cookin' your innards. It's kind of difficult to accidently get between the phases in a ground-fault scenario. But 277 is a phase-to-ground voltage. Grab hold of one phase, and you've still got 277.

that is a good point!

 

[LarryFine]

that is a good point!

Yeah, he does that from time to time. That's why we keep him around.

 

[wasasparky]

I'm aware that the 1987 code edition required lighting that was within a certain distance from the floor or grade (say 7'-6" for example) to be wired to a 120V source.

Partially true - the limit was 8' for screw-shell lampholders.
There were several exceptions including ballasted fixtures, etc...

 

[LawnGuyLandSparky]

Partially true - the limit was 8' for screw-shell lampholders.
There were several exceptions including ballasted fixtures, etc...

Because this code was minsunderstood, a complex of 5 schools in NYC (High school, 2 intermediate and 2 elementary) with 277v lighting (probably the first, and last) was fitted with a low-voltage momentary contact switching system.

Built in the 70's, when 480v services were all the rage and, the story goes that the contractor thought that the wall switches would be in violation, could kill young students, and convinced the engineers to add a safe code-compliant switching system.

Do this day, as you pass those buildings at night - at least 1/2 the classroom lights are stuck on.

 

[dbuckley]

240 is a phase-to-phase voltage. Get between one phase and ground, you've got 120 volts cookin' your innards. It's kind of difficult to accidently get between the phases in a ground-fault scenario. But 277 is a phase-to-ground voltage. Grab hold of one phase, and you've still got 277.

240V may be phase to phase where you live, but where I live these days it's 240V phase to ground. So if I somehow contrive to get myself between the hot and something grounded, I've got the full monty 240V cookin' thing going on. So best advice is not to become that hot to ground bond, whatever the voltage.

 

[tshea]

I dont think I have ever seen 277 or more in a home.

Except when I was messing around with the buck-boost transformer....

 

[480sparky]

240V may be phase to phase where you live, but where I live these days it's 240V phase to ground. So if I somehow contrive to get myself between the hot and something grounded, I've got the full monty 240V cookin' thing going on. So best advice is not to become that hot to ground bond, whatever the voltage.

Just out of curiosity, where do you live?

 

[frenchelectrican]

240V may be phase to phase where you live, but where I live these days it's 240V phase to ground. So if I somehow contrive to get myself between the hot and something grounded, I've got the full monty 240V cookin' thing going on. So best advice is not to become that hot to ground bond, whatever the voltage.

Sure i get nailed from 240 Volts Line to Netural [ common in European area ] [ some area did used 120 L-N but not much ] and 415 Volts L-L

But i got nailed with 600 Volts DC and got it away alive even i did used proper LOTOGO [ Lockout Tagout Groundout ] prodcure and someone did ingore it and i got nailed pretty hard.

but for the AC system either NA[ North Americian ] or EU [ European union ] it dont make much diffrence which one will nail ya hard both about the same

Merci, Marc

 

[LawnGuyLandSparky]

frenchElectrician, what is the code in Europe concerning countertop outlets and spacing?

 

[frenchelectrican]

frenchElectrician, what is the code in Europe concerning countertop outlets and spacing?

Unforetally they are not uniform on this part on the code because each area have difffrent set of codes but AFAIK majorty of them used the RCD aka GFCI and the countertop repectales are spaced a metre apart [ 3.1 feet ] and will useally have at least 2 SABC with 16 A circuit's but if the appalince required 32 A or higher useally hardwired either in 1 ? or 3 ? format

and useally required a local disconnecting switch as well for high current devices.

for majorty of lighting circuits useally are not RCD'ed but it can change the code depending on the area.

Merci, Marc