DIY Home Improvement, Remodeling & Repair Forum > DIY Home Improvement > Electrical and Wiring > Range wiring




Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old 12-13-2009, 05:30 AM  
speedy petey
Lic.Electrical Contractor
 
Join Date: Mar 2006
Posts: 445
Liked 39 Times on 27 Posts
Likes Given: 17

Default

Quote:
Originally Posted by rdmayers View Post
Texas asked the question if it was done correctly.I can not answer this until i find out how the #10 neutral gets there.Is this so had to understand.Everyone want to reply,but nobody want to answer my question
I don't think any of us can accurately answer this, not just you.
Texas posted this one and only post two nights ago and has not been back since. EVERYTHING from here on out is purely speculation until (unless) he returns.


Actually, unless there are other problems/circumstances we don't know about it is likely a compleltey complaint installation.

210.19 Exc. 2 tells us this:

Exception No. 2: The neutral conductor of a 3-wire branch circuit supplying a household electric range, a wall-mounted oven, or a counter-mounted cooking unit shall be permitted to be smaller than the ungrounded conductors where the maximum demand of a range of 83/4-kW or more rating has been calculated according to Column C of Table 220.55, but such conductor shall have an ampacity of not less than 70 percent of the branch-circuit rating and shall not be smaller than 10 AWG.


__________________
speedy petey is offline  
 
Reply With Quote Quick reply to this message
Old 12-13-2009, 12:10 PM  
Nestor_Kelebay
Emperor Penguin
 
Nestor_Kelebay's Avatar
 
Join Date: Mar 2009
Location: Winnipeg, Manitoba
Posts: 1,844
Liked 2 Times on 2 Posts

Default

And here I got into a bar fight last night with a guy who insisted that "ampacity" was a real word. Now I'm going to have to visit him in the hospital and apologize.

OK, so provided that the 10 gauge wire meets the requirement of being able to carry 70 percent of 60 amps, then we can assume the wiring was done by someone who knew the electrical code, and almost certainly did it correctly.

But, RDMayers point still remains, and I'd like to know (and probably all of the other non-electricians in here, too)... how could that physically be done if you can't buy a cable with an undersized white wire? Would you run a #6 two conductor cable to the range and then what? Have the 10 gauge neutral wire strung across the kitchen ceiling between the electrical panel and the stove and doubling as an indoor clothes line?

Or do they make special cables for ranges with an undersized neutral just because the code allows a smaller neutral in certain circumstances?



__________________

Last edited by Nestor_Kelebay; 12-13-2009 at 12:34 PM.
Nestor_Kelebay is offline  
 
Reply With Quote Quick reply to this message
Old 12-13-2009, 12:48 PM  
speedy petey
Lic.Electrical Contractor
 
Join Date: Mar 2006
Posts: 445
Liked 39 Times on 27 Posts
Likes Given: 17

Default

Quote:
Originally Posted by Nestor_Kelebay View Post
And here I got into a bar fight last night with a guy who insisted that "ampacity" was a real word. Now I'm going to have to visit him in the hospital and apologize.
Well, according to Firefox it is not a word, but I know it is. At least in my world.
Why is he in the hospital? Did he trip walking out to his car and sprain his ankle?




Quote:
Originally Posted by Nestor_Kelebay View Post
But, RDMayers point still remains, and I'd like to know (and probably all of the other non-electricians in here, too)... how could that physically be done if you can't buy a cable with an undersized white wire? Would you run a #6 two conductor cable to the range and then what? Have the 10 gauge neutral wire strung across the kitchen ceiling between the electrical panel and the stove and doubling as an indoor clothes line?

Or do they make special cables for ranges with an undersized neutral just because the code allows a smaller neutral in certain circumstances?
One can only assume conduit. It is certainly feasible.
Since we have yet another MIA thread starter we may never know.
__________________
speedy petey is offline  
 
Reply With Quote Quick reply to this message
Old 12-13-2009, 03:12 PM  
JoeD
Contractor
 
Join Date: Mar 2006
Location: Welland, Ontario
Posts: 948
Liked 100 Times on 82 Posts
Likes Given: 2

Default

Quote:
It's when you put the black and red wires through reactive loads like capacitors (TV sets and CRT computer monitors) or inductive loads (like electric motors and electromagnets) that the current sine waves get out of phase with the applied voltage sine waves. And, when you have the current and voltage sine waves in both the black and red wires out of sync, when they meet at the white wire they won't cancel out completely, and you can have some residual current and voltage in the white wire.
This is not correct. The only time current flows on the neutral is when you need 120 volts. 240 loads even if they are reactive or inducutive will still cancel each other out. A 240 volt welder is very reactive and it has no neutral.
__________________
JoeD is offline  
 
Reply With Quote Quick reply to this message
Old 12-13-2009, 08:01 PM  
Nestor_Kelebay
Emperor Penguin
 
Nestor_Kelebay's Avatar
 
Join Date: Mar 2009
Location: Winnipeg, Manitoba
Posts: 1,844
Liked 2 Times on 2 Posts

Default

Quote:
Originally Posted by JoeD View Post
This is not correct. The only time current flows on the neutral is when you need 120 volts. 240 loads even if they are reactive or inducutive will still cancel each other out. A 240 volt welder is very reactive and it has no neutral.
Let me get back to you on this point, Joe.

My understanding is that people often presume there can't be any current through the neutral wire because it's connected to ground in the main panel. So, if it's grounded at the panel then it supposedly has zero voltage, and therefore can't have any current. But, ask any dairy farmer, and you'll find out about "dirty electricity" where there are voltages and currents in the neutral wire that interfere with their operations. There can be enough voltage in supposedly neutral wires to cause cows to stop giving milk because of the tingling they feel from the very small shocks they get. I'm gonna phone down to the Electrical Engineering Department at the U of M tomorrow and ask what would happen in the neutral wire if there were an inductor connected between the black and neutral and a capacitor connected between the red and neutral.
__________________
Nestor_Kelebay is offline  
 
Reply With Quote Quick reply to this message
Old 12-14-2009, 09:40 AM  
Nestor_Kelebay
Emperor Penguin
 
Nestor_Kelebay's Avatar
 
Join Date: Mar 2009
Location: Winnipeg, Manitoba
Posts: 1,844
Liked 2 Times on 2 Posts

Default

Joe:

The University of Manitoba doesn't have anyone who knows anything about house wiring except the electricians employed there.

I talked to one major electrical contractor this morning and he tells me it's common to have current through the white wire. When they wire electrical outlets for kitchens, they will often cut the tab between the two outlets on a duplex receptacle and connect one outlet to the black voltage source and the other to the red voltage source. They do that because it's common for people to blow fuses or trip the breaker to the kitchen electrical outlet because so many things that get plugged in there draw high current (coffee maker, toaster, microwave, electric frying pan, etc.) So, by providing two 15 amp circuits to that outlet and sharing the neutral, you don't blow as many fuses, but any imbalance in the current ends up going down that shared neutral. If a toaster and blender are plugged in, you might have 10 amps through the toaster and 3 amps through the blender, and the difference of 7 amps will flow through the neutral. However, that same electrician told me that even through there is 7 amps in that neutral, there won't be any voltage in that white wire, and that violates the first principle of electricity. You simply can't have current without a voltage to drive it.

That electrical contractor suggested I talk to one of the instructors at Winnipeg's Red River College where they train electricians, and I did so. I could tell that instructor simply didn't know enough about the subject to have any confidence in his answer, and he suggested I talk to the engineering department at Manitoba Hydro.

Manitoba Hydro employees get every 2nd Monday off, and that just happens to be this Monday. I will talk to Manitoba Hydro's engineering department tomorrow.

Anyhow, I fully understand that such an "imbalanced load" (as described for a kitchen outlet) is not exactly what we're talking about. What we're talking about is a current and voltage in the white neutral wire due ENTIRELY to the red and black voltage and current sine waves not cancelling each other out.

I remain convinced that if those red and black sine waves don't cancel out completely, then there simply has to be a resulting current and voltage in the white wire. There's simply no other option. I'll talk to Manitoba Hydro tomorrow.

__________________

Last edited by Nestor_Kelebay; 12-14-2009 at 09:57 AM.
Nestor_Kelebay is offline  
 
Reply With Quote Quick reply to this message
Old 12-15-2009, 06:51 PM  
Nestor_Kelebay
Emperor Penguin
 
Nestor_Kelebay's Avatar
 
Join Date: Mar 2009
Location: Winnipeg, Manitoba
Posts: 1,844
Liked 2 Times on 2 Posts

Default

Phoned Manitoba Hydro today, talked to two electrical engineers and one electrical engineering technologist, and none of them knew that residential power consisted of two hot wires and one neutral wire with the two hots out of phase by 180 degrees. The technologist had no idea who to even refer me to. One engineer was willing to help, but didn't know that power was delivered via two hots that were 180 degrees out of phase. The other electrical engineer, a supervisor of the department was asking more questions than me... why do I want to know this, what difference does it make, who am I doing this for, etc. etc. etc. Then he just lost interest in the discussion and told me he didn't know the answer and didn't know of anyone who might.

This is getting stupid already. The question isn't difficult, and I'm amazed that no one at Manitoba Hydro is knowledgeable about this.

__________________
Nestor_Kelebay is offline  
 
Reply With Quote Quick reply to this message
Old 12-16-2009, 07:52 PM  
triple D
Senior Member
 
Join Date: Jan 2008
Posts: 296
Liked 1 Times on 1 Posts

Default animal cruelty!

Stop whipping this horse!!!! The only thing in an oven using a neut. is the light bulb, or timer, or cooling fan. The neut is simply not required by code, anywhere, to match current carrying conductor size. Refer to quote in speedy's post.

__________________

[COLOR="DarkGreen"][FONT="Franklin Gothic Medium"]See my work-Check out my album. "Git 'Er Done":D [/FONT][/COLOR]

triple D is offline  
 
Reply With Quote Quick reply to this message
Old 12-17-2009, 06:52 AM  
travelover
Senior Member
 
Join Date: Aug 2007
Posts: 693
Liked 2 Times on 2 Posts

Default

Quote:
Originally Posted by Nestor_Kelebay View Post
....................This is getting stupid already. The question isn't difficult, and I'm amazed that no one at Manitoba Hydro is knowledgeable about this.
Well, I'm not surprised considering that they don't even know that hydro means water and electricity is - well, electricity.
__________________
travelover is offline  
 
Reply With Quote Quick reply to this message
Old 12-17-2009, 12:18 PM  
Nestor_Kelebay
Emperor Penguin
 
Nestor_Kelebay's Avatar
 
Join Date: Mar 2009
Location: Winnipeg, Manitoba
Posts: 1,844
Liked 2 Times on 2 Posts

Default

Oh ye of little faith! Be patient.

I am confident that I understand reactance well enough that if you have an inductive load on one leg of 220 volt house wiring and a capacitive load on the other leg, then where the two amperage waves meet at the white wire, there won't be complete cancellation, and there will be some NET amperage in the white wire.

The issue I'm having now is that the voltage sine wave HAS TO BE affected by the inductor. If it wasn't, then the voltage sine waves would cancel completely, and I'd be standing here saying that there's a net amperage in the white wire WITHOUT any associated driving voltage in that white wire. (and, like, hey man, you can't have current without a driving voltage) If there's smoke there fire, and if there's current, there's voltage.

So, that's where things stand right now. One of these days I'm gonna take a drive down to the U of M.

PS: The horse tells me that he's wanting to know the answer too. The horse tells me he's always understood that the current sine wave is affected by impedance, but agrees that the voltage sine waves can't cancel completely cuz then you'd have current without voltage. He's a smart horse.



__________________
Nestor_Kelebay is offline  
 
Reply With Quote Quick reply to this message
Reply


Quick Reply
Message:
Options

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter DIY Home Repair Forum Replies Last Post
1926 Roper gas range HELP! nancyl General Appliance Discussion 0 09-17-2009 10:40 AM
LP range burns too hot guyod General Appliance Discussion 7 04-14-2008 12:24 AM
Wiring up range hoods and bathroom fans dble_g2k Electrical and Wiring 2 10-10-2007 06:35 PM
Estate Stove Co. Gas Range - Need Help! bobbisue General Appliance Discussion 3 06-08-2006 11:09 PM
Replacing Stove Top with Range the.vicster Electrical and Wiring 1 02-24-2006 06:05 PM