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Wiring question

schloaty

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I recently disconnected a hot tub (replacing it with a green house) and I want to use the same dedicated circuit to power the greenhouse equipment.

Only problem is, there is an extra wire! I have a red and a black wire that are connected to the juction box, a green wire that is grounded, but there is also a (much thicker) white wire was (if I remember right) wired directly to the tub (by passed the junction box entirely).

What the heck is this white wire?

What would I do with it if I wanted to wire in an outlet?

Thanks for any help! I can post a pic of the juction box if it would be of any help...
 
The white wire is the Neutral -- It must be connected to any equipment that only uses 120 VAC. The black is a 120VAC hot line and the red is the other 120VAC hot line, together they provide 240VAC to equipment that uses 240VAC exclusively, in those types of equipment the neutral is not needed, just the two hot lines and the green - ground. In any equipment that uses 120VAC for any component, the neutral is needed to complete the 120VAC circuit.

In other words for 240VAC equipment the 240VAC flows (both ways) through the black and red wires, but in 120VAC equipment the white - neutral wire is needed to complete the 120VAC circuit and allow the current to flow (to and from the source).

In your case the white wire is probably larger than either hot wire because the hot tub likely had both 120VAC and 240VAC devices operating in it. Though the 240VAC devices may have used more power, it was delivered to them more efficiently at the higher voltage. 120VAC devices are somewhat less efficient and since there are two different "legs" of 120VAC, the red and black, they theoretically need the larger neutral to complete their path back to source since they are likely not balanced as 240VAC circuits would be.

As you observed the white wire does not go through any switching devices, it, like the green or bare grounding wire must be continuous and never broken. Since it is used to complete any 120VAC circuits, when those devices are operating it carries current and is HOT.
 
I can attest hot tubs are 240. I had one as well, but mine had a 30 amp 240VAC breaker and a 20 amp 120VAC. The only thing that runs on 240VAC is the heater. Everything else runs on 120VAC.
 
OK MOVE OUT OF THE WAY AND LET THE ELECTRICIAN THOUGH.



I agree with what was said here except for a couple of minor points.

[b said:
Quote[/b] ]The black is a 120VAC hot line and the red is the other 120VAC hot line, together they provide 240VAC to equipment that uses 240VAC exclusively, in those types of equipment the neutral is not needed,

Not entirely true. By code the hot tub should be wired through a GFCI. (Ground Fault Current Interrupter). These devices are what's in most bathrooms with the red and black buttons. They keep you from getting fried if you drop the hairdryer in the tub. They are required anywhere that is within 6ft of a water source or outside. Since the hot tub is a water source it has to be GFCI protected. GFCI's require a neutral to work. There are other 240v objects that requires a neutral, Stove and Dryers requires a neutral.

[b said:
Quote[/b] ]n your case the white wire is probably larger than either hot wire because the hot tub likely had both 120VAC and 240VAC devices operating in it. Though the 240VAC devices may have used more power, it was delivered to them more efficiently at the higher voltage. 120VAC devices are somewhat less efficient and since there are two different "legs" of 120VAC, the red and black, they theoretically need the larger neutral to complete their path back to source since they are likely not balanced as 240VAC circuits would be.

I really don't know why the neutral is bigger. There is no reason for it to be. I agree with most of what was said above. When you say power regarding electricity, you are not talking about voltage, you're talking about amps. A 240V device will use roughly half of the power of a 120V device. So that's what makes higher voltage more efficient. It's about the same as trying to drive a stake in the ground with a 16 oz hammer verses a 5lb hammer.
You're right about the power from the two hot legs (Black and Red wires) traveling back on the same neutral wire. But the neutral wire only has to be rated the same as the hot wires. Even though it is carrying double the load. There is a very smart way this is done. (Thanks to Nikolos Tesla for designing a better electrical system than what Thomas Edison had) Look up "War of the Currents" Very interesting and it deserves it's own topic here. In the USA electricity is on 60 hertz. That means 60 times a second there is a pulse of electricity sent through the each wire. The hot legs alternate, meaning that there is never electricity on both wires at the same time. They take turns. So the neutral never has more power on it than a single hot leg, but it has twice the power because instead of it being 60 hertz it's 120 hertz. That's where the name AC (Alternating Current) comes from. The USA has a 3-phase system which is even more efficient than Single Phase 240V. It's is the same as I described above except there are 3 hot wires instead of two. This system is used for bigger buildings like stores, restaurants, office buildings, ETC.


OK what was the original question? Oh yeah hot tub and greenhouse. Dave send me pics of where the hot tub wires come out and the hook up of the green house and I'll get you going in the right direction.
 
[b said:
Quote[/b] ]What the heck is this white wire?

Any IDIOT would know what that wire is.
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Maybe you should pay somebody like an electrician to come out there and tell you what that wire is. After all...people that stupid SHOULD pay for being so stupid.

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laugh.gif
 
I agree, I'll come take your money. Or you can pay me in Dave's firey sauce.

And no Pak that is not what I meant.
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[b said:
Quote[/b] (PlantAKiss @ Aug. 15 2006,5:38)]
[b said:
Quote[/b] ]What the heck is this white wire?

Any IDIOT would know what that wire is.  
smile_l_32.gif
  Maybe you should pay somebody like an electrician to come out there and tell you what that wire is.  After all...people that stupid SHOULD pay for being so stupid.

smile_n_32.gif
 
laugh.gif
Harsh...
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PAK, you need an "outlet" to vent that angst.
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This amateur will add that you should never assume anything when working with wiring in older houses.  Just because a wire should be something doesn't mean it actually is.  Remember that previous owners as incompetent as us each had an opportunity to really screw things up.

Whenever there's any doubt, test and make sure wires are what you think they are.  And there should always be doubt.  It's amazing how often grounds aren't grounded.  And definitely don't take my (former) shortcut of thinking it's safe to work downstream of a wall switch without tripping the circuit breaker.  I got shocked that way once and figure someone must have switched the neutral instead of the hot wire.

Since I'm not methodical enough for my own good, I've pretty much quit doing wiring and I long ago gave up the illusion of doing plumbing.
 
[b said:
Quote[/b] ]Harsh...  

PAK, you need an "outlet" to vent that angst.

ROFL!

Well...I'll agree with you that I need an outlet...  
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...BUT... I can't afford to pay an electrician to come and put one in. lol

Actually...I was just repeating the same thing Schloaty said to that poor, sweet woman who forgot to flip her breaker switch.  Schloaty was encouraging Ozzy to ra pe her with high fees for just a simple switch flick.

I'm just trying to stick up for her.  I think she's probably a very nice person who had the heat get to her brain and suffered a temporary lapse in common sense.  
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  • #10
Ozzy, be a nice guy and drive up and install an outlet for PAK.
 
  • #11
Actually, I could use numerous outlets...upstairs bathroom and hallway, breakfast room, etc. I have some loose outlets too. Are they dangerous if they are about to fall out of the wall? I could definitely keep an electrician busy. But, I can't afford their HIGH FEES.
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  • #12
[b said:
Quote[/b] ]After all...people that stupid SHOULD pay for being so stupid.

And I stand by this statement. To admit to lack of knowledge is the mark of wisdom, not stupidity.

This woman of whom you speak was stupid because she did not ask around, but instead jumped straight to hiring an electrician.

I WILL pay an electrician for his or her knowledge if this is something that I am wise enough to realize too risky for me - however I will also exercise enough wisdom to ask around BEFORE I spend my hard earned cash.

smile_n_32.gif


Ozzy, I'll take a pic of the electrical hookups I have - haven't actually purchased any outlets yet, so I can't show you that end, but I can show you what's currently (NPI) in place.
 
  • #13
[b said:
Quote[/b] ]This amateur will add that you should never assume anything when working with wiring in older houses.

True so true.

[b said:
Quote[/b] ]And definitely don't take my (former) shortcut of thinking it's safe to work downstream of a wall switch without tripping the circuit breaker. I got shocked that way once and figure someone must have switched the neutral instead of the hot wire

I did the same thing once when I was 15. I assumed that if the switch is off then there is no way that there can be electricity in the light. I was SO WRONG. I got shocked, and I couldn't understand why.
Your theory of the neutral being switched is possible. As a matter of fact that's the way it was done decades ago. More likely though the light was what electricians call "back fed" The hot wire is taken to the light and a 12/2 romex is taken from the light to the switch. One wire is the hot and the other is the switch leg. When you do this, you have to make the white wire hot. So if you assume that the white is always a neutral, you can be dead wrong.


[b said:
Quote[/b] ]Actually...I was just repeating the same thing Schloaty said to that poor, sweet woman

Sweet woman, you obviously have never met her. I wish I could state here how I felt about that woman but the filter would change my words all around. I can't state how I feel about her here.
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All I can do is quote Ricky Bobby. "Shake and Bake"

[b said:
Quote[/b] ]Ozzy, be a nice guy and drive up and install an outlet for PAK.

Ok I'll do my part. I'll work for almost free, if we take up a collection for gas money and materials I'll need to do the job. I will even fix her AC problems.

[b said:
Quote[/b] ]I could definitely keep an electrician busy. But, I can't afford their HIGH FEES.
smile.gif

Don't lie you have enough to pay the bill.

Dave, show me the pics of both the green house hookup and the hookup from the house before you buy the connectors. I may be able to save you some time. You don't want to buy the wrong ones.
 
  • #14
[b said:
Quote[/b] ]Ok I'll do my part. I'll work for almost free, if we take up a collection for gas money and materials I'll need to do the job.

Almost for free? There ya go...charging yet another poor, sweet woman an exhorbitant fee.

I say a ham biscuit oughta be a-plenty. lol
 
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