Cord cut. How do I determine which wire is hot and which is neutral?

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Elstupido

Senior member
Jan 28, 2008
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It may or may not matter on a power supply, however, I would go through the effort to wire it correctly, hot wire on L1, neutral wire on L2.

And yes some older lamps were not polarized, and you could get a good shock from screwing in light bulbs if you touch the screwshell of the bulb
 

sdifox

No Lifer
Sep 30, 2005
97,658
16,560
126
Originally posted by: boomerang
Assume you have an A/C circuit with two wires. One is black with a wide pronged end and the other is blue with a narrow pronged end.

Which one carries the current?

Some idiot wired that receptacle with a Romex 12/4? White is neutral, rest is supposed to be hot. Unless you are wiring switches for staircases (or 3 phase power), you usually don't go with a 12/4.
 

boomerang

Lifer
Jun 19, 2000
18,883
641
126
Originally posted by: sdifox
Originally posted by: boomerang
Assume you have an A/C circuit with two wires. One is black with a wide pronged end and the other is blue with a narrow pronged end.

Which one carries the current?

Some idiot wired that receptacle with a Romex 12/4? White is neutral, rest is supposed to be hot. Unless you are wiring switches for staircases (or 3 phase power), you usually don't go with a 12/4.
It's an example, nothing more. Calm down.
 

boomerang

Lifer
Jun 19, 2000
18,883
641
126
Originally posted by: Elstupido
It may or may not matter on a power supply, however, I would go through the effort to wire it correctly, hot wire on L1, neutral wire on L2.

And yes some older lamps were not polarized, and you could get a good shock from screwing in light bulbs if you touch the screwshell of the bulb
And your body has a path to ground. But whatever, I see no need to continue the discussion. From previous posts, I seem to remember that you're an electrician. I'm not and I'll concede to your wisdom.

Shit, that sounds like I'm being sarcastic. I'm not trying to be that at all. Truly.

Somebody help out the OP with his last question. Edit: Who's probably regretting he asked it at all at this point. :laugh:

 

sdifox

No Lifer
Sep 30, 2005
97,658
16,560
126
Originally posted by: boomerang
Originally posted by: sdifox
Originally posted by: boomerang
Assume you have an A/C circuit with two wires. One is black with a wide pronged end and the other is blue with a narrow pronged end.

Which one carries the current?

Some idiot wired that receptacle with a Romex 12/4? White is neutral, rest is supposed to be hot. Unless you are wiring switches for staircases (or 3 phase power), you usually don't go with a 12/4.
It's an example, nothing more. Calm down.

:) I get emotional when people fuck up in wall wiring.
 

Elstupido

Senior member
Jan 28, 2008
643
0
0
Originally posted by: sdifox
Originally posted by: boomerang
Assume you have an A/C circuit with two wires. One is black with a wide pronged end and the other is blue with a narrow pronged end.

Which one carries the current?

Some idiot wired that receptacle with a Romex 12/4? White is neutral, rest is supposed to be hot. Unless you are wiring switches for staircases (or 3 phase power), you usually don't go with a 12/4.

Huh? I am sure he was talking about the cord cap, and not the receptacle. 12/3 romex with ground is used quite often when you want two circuits on one duplex receptacle, such as top half of the duplex circuit for a disposal, and the bottom half, another circuit for the dishwasher, under the sink in a kitchen.
 

sdifox

No Lifer
Sep 30, 2005
97,658
16,560
126
Originally posted by: sdifox
Originally posted by: boomerang
Originally posted by: sdifox
Originally posted by: boomerang
Assume you have an A/C circuit with two wires. One is black with a wide pronged end and the other is blue with a narrow pronged end.

Which one carries the current?

Some idiot wired that receptacle with a Romex 12/4? White is neutral, rest is supposed to be hot. Unless you are wiring switches for staircases (or 3 phase power), you usually don't go with a 12/4.
It's an example, nothing more. Calm down.

:) I get emotional when people fuck up in wall wiring.



Op, I am assuming you found the picture from a polish website? Or is the machine from Poland? They are on 230vac.
 

sdifox

No Lifer
Sep 30, 2005
97,658
16,560
126
Originally posted by: Elstupido
Originally posted by: sdifox
Originally posted by: boomerang
Assume you have an A/C circuit with two wires. One is black with a wide pronged end and the other is blue with a narrow pronged end.

Which one carries the current?

Some idiot wired that receptacle with a Romex 12/4? White is neutral, rest is supposed to be hot. Unless you are wiring switches for staircases (or 3 phase power), you usually don't go with a 12/4.

Huh? I am sure he was talking about the cord cap, and not the receptacle. 12/3 romex with ground is used quite often when you want two circuits on one duplex receptacle, such as top half of the duplex circuit for a disposal, and the bottom half, another circuit for the dishwasher, under the sink in a kitchen.

why would those 2 need to be on different circuit? Just curious. Don't disposals usually get wired to a switch?
 

Shawn

Lifer
Apr 20, 2003
32,236
53
91
I got the pic from a polish website. Don't know if the US model is any different, but I will be getting the US model.
 

sdifox

No Lifer
Sep 30, 2005
97,658
16,560
126
Originally posted by: Shawn
I got the pic from a polish website. Don't know if the US model is any different, but I will be getting the US model.

I would say red is hot, blue is neutral. IF you follow convention. check the marking on the board.
 

Elstupido

Senior member
Jan 28, 2008
643
0
0
The NEC (national electrical code) requires the dishwasher, and disposal to be on individual circuits. Taking these two circuits to one box and receptacle saves on parts and labor costs.

OP, I can't tell from your pics if the blue wire has a white stripe on it, if so that should be the neutral, or L2 wire.
 

Shawn

Lifer
Apr 20, 2003
32,236
53
91
Ok, that's how I'll wire it up. If I stop posting tomorrow it might not have worked out.
 

sdifox

No Lifer
Sep 30, 2005
97,658
16,560
126
Originally posted by: Shawn
Ok, that's how I'll wire it up. If I stop posting tomorrow it might not have worked out.

I'll keep an eye on google earth and look for thermal blooming. There is no shuttle launch tomorrow right?
 

compuwiz1

Admin Emeritus Elite Member
Oct 9, 1999
27,111
926
126
Originally posted by: Shawn
Ok, that's how I'll wire it up. If I stop posting tomorrow it might not have worked out.

See ya later.......with your new afro! ;)

 

sdifox

No Lifer
Sep 30, 2005
97,658
16,560
126
Originally posted by: compuwiz1
Originally posted by: Shawn
Ok, that's how I'll wire it up. If I stop posting tomorrow it might not have worked out.

See ya later.......with your new afro! ;)

110 is nothing...I've done 110 and 220. 220 blackened my finger...
 

jagec

Lifer
Apr 30, 2004
24,442
6
81
Originally posted by: Elstupido
The shell on the socket is insulated, but the screwshell on the light bulb isn't. Most people don't touch the metal part of the bulb when replacing, but a lot of do.

Meh...while it's true that polarity helps with safety (and it CERTAINLY matters when you're wiring your circuit breakers), anyone who has any business soldering should know enough about electricity not to make stupid mistakes like that.
 

AlienCraft

Lifer
Nov 23, 2002
10,539
0
0
< digging around in old er computer for service doc.s

I seem to remember a color code scheme that desginates colors for Consumer product power cords. Country of origin is key , iirc.
It was on a Roland service document...it may be in file cabinets if that's the case. Never did scan what i was hoping to....

Contry of Origin for the product, or a look inside... If there's a transformer on the front end of the power supply, it really doesn't matter.

 

AlienCraft

Lifer
Nov 23, 2002
10,539
0
0
Strip back the cut part and let us see the colors on the conductors. Ground is easy and the other two is a toss up.
 

AlienCraft

Lifer
Nov 23, 2002
10,539
0
0
Originally posted by: Demon-Xanth
Black or Brown=Hot
White or Blue=Neutral
Bare, Green, or Green with a Yellow stripe=Ground

trhere you go.

cuts and pastes this into a new notepad file....
 

5to1baby1in5

Golden Member
Apr 27, 2001
1,245
106
106
Originally posted by: boomerang
Originally posted by: compuwiz1
There is no polarity on A/C it does not matter. 1 of 2 ways to connect. Either way will work just fine.

Hello! Did anyone read this?

This is not exactly correct.

Yes, the device will still work no matter what the polarity.

The Neutral, however, will be at the same voltage as ground. You could touch it while grounded and not get zapped.

L1 (hot) oscilates between +120 V and -120 V relative to the neutral. If you touch it while grounded, then you will get shocked.

L1 is supposed to be wired to a power switch incase the device shorts out internally, you will not be sending power to the chassis when it is turned off. If it shorts internally while turned on, then it will blow the breaker.

In this case, the AC power goes directly to the main board and to a DC power supply. The DC power supply is most likely energized all the time, and is switched on via a DC power button. In this case, it may not matter how you wire it.

--------------------------------

If you look at a lamp chord, then you will notice the insulation has a ridge along one of the wires. This helps you track the polarity of the wires. The ridge is supposed to go to the wider prong (Neutral). Check your chord for this ridge. If it is there, then you will know which wire is L1, and which one is Neutral.
 

mrSHEiK124

Lifer
Mar 6, 2004
11,488
2
0
The DVD player at my grandparents house overseas always shocks me through the chassis when I try and push a button on the unit. Plugs in Israel aren't polarized unless they have a ground prong, and the DVD player only has a two prong cord; think that might have something to do with it?