Wiring a 480V Single Phase Circuit

[BobB]

NO, you brought up the 277 first, and didn't even realize it.

Do you remember saying this (it's quoted above)?: "At any rate, a better description IMO would have been something like a two wire service, usually one phase of a three phase supply."

If you have, in your words, "a two wire service", and ONE of the wires is "one phase of a three phase supply", the OTHER wire of the "two wire service" is the NEUTRAL. One phase to ground IS 277 volts on the system that I mentioned.

Like Chris said, scope two phases of a 3 phase system......the waveforms combine to make a SINGLE waveform.

I could care less how it is derived, however if you get it from the power co., its gonna be 3 phase. The OP stated that he was familiar with 3 phase power, so gee, a discussion of how to derive single-phase

480 from a 277/480 volt 3 phase Wye connected system didn't seem OT to me. When discussing a 277/480 system, it doesn't hurt to also mention that 277v SINGLE-phase can also be derived from line-to-neutral while stating that the 480 single-phase is line-to- line.

....snip....

distribution is

Gee Wally, if it were _that_ far off OT, where do you think a lot of people get those kind of lights for growing reefer (AS WAS PREVIOUSLY DICUSSED)???????? Can you say 480volt SINGLE-PHASE ballasts from parking lot lights that Sparkies threw away when they were installing new lights?

Looks like YOU are the > > >

Looks like YOU are the one who needs to f*ck off.

......snip.....

and you can get a job as a commercial/industrial electrician sometime and find out real fast that 480 volts single-phase derived from a 3 phase 480v system is any two phases line-to-line.

How many times do you have to be told? When two phases of a 3 phase system are combined, THE RESULT IS A SINGLE VOLTAGE WAVEFORM?

[Volts500]

Excuse me? My first reply to you was _civil_, YOU are the one who started with the cussing and the put downs. One of those dish it out but can't take it kinda guys, eh? It was OK for YOU to call me a stupid ass the other day in alt.hvac after you displayed total ignorance of the topic being discussed, just like you're doing now, but when I return the favor you cry like a baby. Point is....don't post stupid crap and you won't have to whine about being corrected.

[PrecisionMachinisT]

Like what--stating some c*ck and bull story alluding that single phase would always come from a three phase source, then sticking to it come hell or high water ???

....LOL....

At any rate, fishin season is pretty much over here at least for the time being.......I would go back and argue some more but seems pointless--what a piece of work you are, and I do mean that as a complement.

If you care to explain to us one more time what single phase current is, appreciate if you could do it without any reference to polyphase systems--this because generally one should have a working knowlege of these before moving on to the various three phase distribution stuff, instead of it being the other way around--and because in your very first reply you stated to the effect the OP didnt understand polyphase systems despite his initial claim to the contrary.

Cheers,

[TURTLE]

This is Turtle.

So After the voicing your anger, What do you have to say about it.

TURTLE

[Volts500]

Get your facts straight, if your gonna try to use it as a put down, ya chump. It was bleed over from the "Package Unit Wire/Amp Rating" thread, you know it. You know, where you found it necessary to check-in as a cluless moron (along with many of the others in the alt.HVAC subgroup of alt.H(ack)VAC flex/fiberboard duct boys), just like you found it necessary to check-in as a moron in _this_ thread.

Here's YOUR clueless post :

Message-id:

"You stoopid ass.

The breaker size is dependant on the wire gage--and it is to protect the wire.......makes no differance if there never gets a load connected to it at all, ever......

Matters not if you connect a 100 amp load to a # 10 wire with a 30 amp breaker--sure it will trip the breaker, but the important thing is it will trip the breaker before the wire catches fire.

[Volts500]

No anger here, Turtle, just speaking to 'em in their own language. I believe that I had most of my say in the "Package Unit Wire/Amp" thread in alt.hvac. and in the bleedover in a few other threads. But now that you bring it up, there are a few more things on my mind. If PJM and his cronies are so adamant about "homemoaners"(as HE and others call them) posting in alt.hvac, and seem to enjoy the personal attacks on them, WHY is it that at least ONE of the regulars over there can't find the time to post the FAQ so that homeowners know not to post there? I also find it interesting that the very same people get their bread buttered by hardworking homeowners find it necessary to refer to the hand that feeds them, in a public forum of all places, as "homemoaners?

[PrecisionMachinisT]

"Bleedover" huh.....so you can do that but not me ???

Find fault with the statement--remember, the intended load has not been defined as of yet..........

Chump must be a really serious insult where you are from........means little to me though--do they let folks use computers in the joint???--just curious, as I've heard certain things.........

==========

...................Okay, back to square one here...........................

I have 120/ 208v service, what is 277v single phase ???

Do I need a three phase service to operate a 480v single phase load ???

What is "single phase" ???

How many ways can it be produced ???

=========

What a fish........

Ya ever stop to consider you just *might* be taking these usenet

*discussions* a bit TOO seriously???

[Chris Lewis]

According to PrecisionMachinisT :

"Two phases from a three phase circuit" is a single phase circuit. How it's derived isn't really relevant at the point-of-use.

The confusion arises out of the word "phase".

Technically, "three phase" describes the circuit itself. When you "take two phases" from a three phase circuit, "take two phases" is slang for what would have been more clearly said as "taking two of the three hot conductors".

What does that have to do with the situation at hand?

That's also correct, but doesn't imply (as perhaps it should) that the two wires are hot wires. Not one of the hots and a neutral, for example.

[Chris Lewis]

According to Jake :

Out of curiousity, I did a few google searches.

H'm. At least some commercial grade grow lamps run at 480V.

See, for example, the GLX series of fixtures:

[Pop Rivet]

Do any of you guys realize what "phase" means? It's not -just- the hot wire - there also has to be a phase difference in the voltage in each wire to generate the required voltage IFF it's more than a single-phase system. 480Vac single phase is pretty standard stuff in industry as is showing up here.

Pop

used for.... my

stories on these

480V.

named after them.

[bitzah]

/me hands the man a star

..and has been for years elsewhere. In Aussie we have been manufacturing and installing 415 Ø fan motors for the refrigeration industry for years ! It is also common practice (or was) to connect Refrigeration systems with a 415 Ø control circuit..giving the added no cost protection of a simple phase failure unit...but I wabbit on..sorry. Thanks for your heads up :-)

BTZ

[PrecisionMachinisT]

Im not confused, someone else is confused about some apparent percieved confusion--you just got caught in the crossfire is all.....

Absolutely nothing, except to demonstrate you can generate OR pick a single phase and generate three phases from it.

Notwithstanding, I *will* concede that at most any modern commercial power plant, three phases are generated......sheesh....pertty sure theres generally three syncronous alternators upon a common shaft electrically linked via a wye connection.....

Hell, I'm a machinist, myself and many others like me actually make the damned equipment.........

If I look closely I can see bits *I* actually made in these photos :

If Mr. Volts500 Sparkie0 dude can puff his chest and brag, then why cant *I* ?

Unless its corner grounded delta, or some other obscure and likely obsolete transmission system, granted, no.

Point being, while it is one thing to have a specific service into a facility, and then only purchase equipment that will easily integrate into the existing plant electrical distribution, it is quite another to have the knowledge and ability to interface equipment having different needs into an existing system--480 v single phase can be easily supplied to most any equipment.....pretty much regardless of the existing AC service, be it three phase or single, so long as it is capable of handling the amperage draw of the connected load.

Cheers,

[PrecisionMachinisT]

"homemoaners?

Well, Im not Turtle, but......

But alt.havoc is like a big family there.

However dysfunctional you choose to view is up to you.

Remember, you are now a part of this extended Errrr "Family"................

[bitzah]

snip

I suspect that the very form of elitism that exists on the beer Swillers Porch that is ... Another Hackers Vocal Arsewipe Circus ...precludes any such warning. My guess is the indigenous expect people to read the A.HVAC Charter which (apparently) invites only Professionals to discuss HVAC at a Professional level. Sadly the inhabitants need to revisit the intent of the Charter,, at least IME. That said,, the forum was not always that way inclined,, However too many Xmas's and too many ClicktyKlik WinBloes versions later,, it is the way it is :-(

Sad but true.

BTZ

[Greg Epperson]

480 single phase is simply using 2 of the 3 hot legs. Phase to phase is 480, Phase to ground is 277vac which we use only for lighting.

[Dean Hoffman]

It's funny how these old threads pop up now and then. But anyhow, single phase in my little world can be 480 line to line and 480 line to ground. I think it's called corner ground delta. Some rural utilities here in Nebraska use it to supply irrigation well motors. We run four wires from the service disconnect to the pump panel. The neutral and equipment ground are connected in the meter. The grounded leg isn't generally supposed to be fused.

[Dean Hoffman]

Oops. Dummy attack on my part. What I described above is one version of 3ø 480. We also do have single phase 480 which is just double normal household voltage. We add a phase converter to create 3ø

480 to power irrigation systems.

[gfretwell]

I have seen a lot of 240 corner delta for sewer lift pumps. The service looks exactly like regular 120/240 except it is fed from 3 transformers. (2 pole breakers with a neutral bus). The first time I saw one it had me going fir a minute. They had 3 phase pumps on something that looked like single phase

[rricha04]

replying to Pop Rivet, rricha04 wrote: How about a plasma cutter like Hypertherm Powermax 85 Input voltages: CSA 200 ? 480 V, 1-PH, 50/60 Hz

200 ? 600 V, 3-PH, 50/60 Hz CE 380/400 V, 3-PH, 50/60 Hz Input Current @12.2 kW CSA 200/208/240/480 V, 1-PH, 70/68/58/29 A 200/208/240/480/600 V, 3-PH, 42/40/35/18/17 A CE 380/400 V, 3-PH, 20.5/19.5 A

[William Ross]

replying to Joshua, William Ross wrote: Looks like you bought an overseas appliance. This is why you need a transformer when American and traveling abroad.