Wiring a new outlet (new to old style)

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Jay H

New Member
Nov 20, 2006
659
NJ
For sanity sakes, I want to make sure I did this right. Last night I wired a new basic 15A outlet to my dining room which must of been an addition to the house, many years before I lived there. For some reason, there is only 1 outlet in the entire room so I wanted to add another one that was easily accessible via the shared wall it shares with my living room. A lot of my electrical is old BX style with the metal sheath that is also used as ground. As such, the junction box is metal and has a metal plate and screw that is used to compress the BX shield (as ground) to the metal junction box so the entire box is grounded. At least it tests fine with my basic simple electrical tester.

I have some new Romex style 14/2 + ground and a new plastic junction box and 2 new outlets that I used. One to replace the old existing outlet (might as well) and 1 for the new outlet I've installed. I hooked up hot to hot and white to white as you'd think and I hooked up the ground wire from the ground tab on the new outlet (green screw) and just hooked that to the metal plate that screws the entire BX cable to the metal box as that is the existing ground. I tested the new outlet and it shows up fine on my circuit tester and everything works but just want to make sure this was the right way to do this? I don't need to connect the *old existing* outlet's ground tab to the metal box too do I? Just want to do things right...

Jay
 
OK, that makes electrical sense and it's not hard for me to get in there and wire the old outlet ground to the metal box...

Jay
 
Jay H said:
For sanity sakes, I want to make sure I did this right. Last night I wired a new basic 15A outlet to my dining room which must of been an addition to the house, many years before I lived there.

I have some new Romex style 14/2 + ground and a new plastic junction box and 2 new outlets that I used.

There is a difference between what is basically safe, what prevents voltage drop to excess, and what is allowed under code by an inspector.

By code as used in most areas - the new outlet is not required to have a ground wire attached to the ground screw ONLY if it fastens directly to the metal box. If it sits away from the box on it's "plaster ears" on the finished wall - it IS required to have the ground wire attached.

I'd be more concerned about wire-sizes. You mentioned having armoured cable, but what size wire gauge and what size fuse or breaker protects it? 14 gauge wire is rarely used in circuits other than for lighting due to the severe voltage drop. If your original armoured cable is 12 gauge - you should NEVER attach a 14 gauge wire to extend it. If it IS 14 gauge all the way, then I assume it is on a 15 amp breaker or fuse. That is rarely done anymore. The amp-rating on the actual plugs you put in are usually 15 amps for the plugs themselves but 20 amps for pass-through. Most household circuits for duplex outlets are 20 amps protected and 15 amps at each set of plugs. Some places also require a few 20 amp rated plugs that have the alternative slots in them (horzontal and vertical).

I'm not trying to confuse the issue. Just mentioned since you did not mention the BX wire gauge. Never mix wire sizes. Wire size for saftey reasons matches fuse/breaker to wire size. Wire size for voltage -drop reasons is different.
 
This is basic indoor 15A circuit. I didn't measure but a layman's eye, it looked like the same gauge wire.

I wired a 20Amp circuit for outdoor yard tools before and used 12gauge about a year ago but this is your standard indoor circuit.

Jay
 
Your post caught my eye - be sure that the circuit breaker connected to this new outlet is no greater than 15amp. Generally, household electrical outlets are required to be 20A - although years ago things were different. If you have a 20A or greater breaker, simply change the breaker to a 15A and you'll be fine.
 
these are 15amp "pushmatic" type breakers. Yeah, it's an older circuit panel....

Jay
 
jdemaris said:
Jay H said:
For sanity sakes, I want to make sure I did this right. Last night I wired a new basic 15A outlet to my dining room which must of been an addition to the house, many years before I lived there.

I have some new Romex style 14/2 + ground and a new plastic junction box and 2 new outlets that I used.

By code as used in most areas - the new outlet is not required to have a ground wire attached to the ground screw ONLY if it fastens directly to the metal box. If it sits away from the box on it's "plaster ears" on the finished wall - it IS required to have the ground wire attached.

Mostly accurate statement, however the receptacle must be the self grounding type. here is a pic of one http://www.mikeholt.com/onlinetraining/page_images/1113923850_10.jpg

Personally i always run a jumper wire between the outlet and the box, in situations likes your Jay.

markpee said:
Your post caught my eye - be sure that the circuit breaker connected to this new outlet is no greater than 15amp. Generally, household electrical outlets are required to be 20A - although years ago things were different. If you have a 20A or greater breaker, simply change the breaker to a 15A and you'll be fine.

The only required circuits that must be 20 amps are, the 2 for kitchen, 1 for dining (can be shared with kitchen)bathroom, washer and possibly the garage.

Everything else can be 15 amp lightning and general purpose outlets (bedrooms, studys, hallways, living rooms etc
 
The 20amp circuit requirement though must be new because all the breakers in my house are 15amp, except for when the previous owner had a pool and a filter and he had a 20amp circuit running there. Since the pool is no more, I used that 20amp breaker and put outlets on the outside so I can run some high amperage lawn tools (and I have an Electric Makita chainsaw that is needs the current)... OK, if the screw in terminal is the ground, the outlet is grounded to the box and my new outlet is grounded to the box too..

Jay
 
Seige, the photo in your link is the perfect example of how one photo is worth a thousand words. Well done!
 
I always loop the ground wire through the ground terminal screw in the box and then directly attach to the outlet... takes five seconds and adds a little stability that stops the outlet from rocking in the box as well - think of tripod vs a ladder... I rarely use the push in connectors on modern receptacles for the same reason, I do it old school and make the loop around the terminal screws - pretty much have to with 12 gauge in your case

20 amp breakers for kitchen receps are a new concept replacing the old dual 15 requirement, but I still prefer split receptacles and they are still allowed, just that it's easier and cheaper to patch in only one 20Abreaker into a box (vs 2x15) and run only a 2/12 vs a 3/14 wire. Best modern electrical code change is probably arc-fault breakers for bedrooms. Wonder how many lives they've saved.
 
Jay H said:
The 20amp circuit requirement though must be new because all the breakers in my house are 15amp

A main reasoning behind using 20 amp circuits for all recepticles is not necessarily to provide 20 amps at an outlet. In fact, most household appliances are limited to a 15 amp draw. The problem is voltage drop. 15 amp circuits use 14 gauge wire - and you can't run 14 gauge wire very far without a substantial voltage-drop. 20 amp circuits use 12 gauge wire and can supply many 15 amp outlets at a farther distance from the main entrance panel.

Usually a 2% voltage drop at most is considered ideal. A 14 gauge copper wire with a 15 amp draw can only be run 30 feet from the main box to stay at 2% and ad 60 feet, there is a 4% drop. 12 gauge at 15 amps can run 45 feet and stay below a 2% drop.
 
seige101 said:
Mostly accurate statement, however the receptacle must be the self grounding type

Mostly accurate? The guy DID say he is using a new 15 amp grounded duplex. To my knowledge, they are all self-grounding and have been for many years.

Different states use different versions of electrical code. New codes are not law, just suggestions until taken on by any particular government entity. In my state of NY, code states cleary exactly what I stated here - when installing a grounded three-prong outlet. Code also allows the installation of a new two-prong non-grounded outlet in "old work" but not in new construction.
 
jdemaris said:
seige101 said:
Mostly accurate statement, however the receptacle must be the self grounding type

Different states use different versions of electrical code. .

Different inspectors in the same town use different interpretations of the code.
 
kenny chaos said:
Different inspectors in the same town use different interpretations of the code.

Yes, and it's the same with code enforcement officers doing buiding-code inspections in general. They can use their own discression and either allow certain features that the printed code does not permit, or disallow features the printed code does allow. In other words, they are empowered to take each inspection on an independent basis depending on the overall situation.
That's why it's usually not a good idea to piss off a code officer even if you know, for sure, he or she is wrong about something. Been through this many times. Once they tell you "no", even if you are right, you have to puruse in court. Easier to acquiesce at the beginning.

I went through this recently with the county head of code enforcement in a northern Michigan county. He did not know his a*s from a hole-in-the-ground and was wrong on many issues -easily proven in the writing in their own code that I suspect he never read. I had to pretend otherwise to get done what I needed to do. I suspect telling him he was a fool would not have gotten me very far.
 
Getting way off topic here but it's been my experience that "hard" code enforcers are really very easy to have removed for residents, commercial's a different story. I've never been afraid to remind one who he works for.
 
jdemaris said:
kenny chaos said:
Different inspectors in the same town use different interpretations of the code.

I went through this recently with the county head of code enforcement in a northern Michigan county. He did not know his a*s from a hole-in-the-ground and was wrong on many issues -easily proven in the writing in their own code that I suspect he never read. I had to pretend otherwise to get done what I needed to do. I suspect telling him he was a fool would not have gotten me very far.

Amen, I once had an electrical inspector fail my new panel install in my cottage.. reason "Failed to bond ground to incoming propane lines" . I didn't have any propane lines, no tank, no natural gas etc... He might as well have written down "Failed to bribe inspector".

Had to get a certified electrician in to make the required "correction" which consisted of a fruitless hunt for the non existant propane lines, a cup of coffee and talking about how stupid the inspector is and what other mistakes he made on a regular basis. Cost me sixty bucks for the signature. Damn bureaucrats.
 
Just to let all of you know, If you have that old BX in your house that is considered a non grounded wire. The newer BX has a small aluminum strip in it to help carry current with the outer jacket back to ground in case of a fault. It was the second generation wire invented B meaning type B, X meaning experimental. It took the place of knob and tube and the outer jacket was considered protection only. Yes it does appear to be a ground if you use your meter and test from the hot to the outer casing or the box. What happens when you put power to a coil? It heats up, this can start a fire in the walls by using the jacket as a ground if there is a short circuit. Just replace with a non grounding outlet, they still make them. Also if you are extending the circuit from that older bx, even if you are using newer grounded romex. The branch circuit is still considered non grounded.
 
RJP Electric said:
It took the place of knob and tube.


Just a side-note. I had to install some new knob-and-tube circuits at a museum site recenty - in areas frequented by the public. It was allowed by code in this situation and passed inspection.

Still quite a few houses in my area with knob-and-tube in the attics.
 
RJP Electric said:
The newer BX has a small aluminum strip in it to help carry current with the outer jacket back to ground in case of a fault. It was the second generation wire invented B meaning type B, X meaning experimental.

Interesting. I've never seen anything writtten about who chose the letters "BX."
Where did you get that info from?

When I was a kid, many old-timers called it "Greenfield Cable." Ed Greenfield invented it, and I know that BX was a brand-name from one particular company. Code classifies it as type AC cable.

The inventor called it "armored hose."
 

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jdemaris said:
RJP Electric said:
The newer BX has a small aluminum strip in it to help carry current with the outer jacket back to ground in case of a fault. It was the second generation wire invented B meaning type B, X meaning experimental.

Interesting. I've never seen anything writtten about who chose the letters "BX."
Where did you get that info from?

When I was a kid, many old-timers called it "Greenfield Cable." Ed Greenfield invented it, and I know that BX was a brand-name from one particular company. Code classifies it as type AC cable.

The inventor called it "armored hose."

Type AC is the new BX with the bonding strip called Armored Cable. The old stuff is not classified by the NEC.
 
RJP Electric said:
Type AC is the new BX with the bonding strip called Armored Cable. The old stuff is not classified by the NEC.

BX has always been a specific brand name, just as Romex and Band-Aid is.

I've got AC cable specifically referenced in 1940s electrical code books - not BX. I can't comment on earlier documents since I don't have any code-books older than that.

AC stands for "armored cable." MC is a later modification and I believe stands fo metal clad - even though some MC cable is not clad with metal. Old AC cable has no extra bonding strip and newer AC does. MC has a insulated ground wire and comes in many versions.

The legend of where the letters BX comes from - is still unclear as far as I know. I studied electric theory and history in the 60s, and at that time many people who were experts in the field, claimed "BX" stood for Bronx, NY because that's were General Electric Co. manufactured it. BX was a registered trademark of General Electric Spraque Division.

I've also heard a few versions of the BX origin you mentioned, but never seen any proof of it.
 
RJP Electric said:
Type AC is the new BX with the bonding strip called Armored Cable. The old stuff is not classified by the NEC.

I just checked some old electric history books. The classification of AC (armored cable) for Greenfield's invention was fomally adopted by the NEC in 1932. This was the stuf the some people have called BX after the General Electric brand name.

The bonding wire that was later added became a requirement under NEC code in 1959. Still called AC.
 
jdemaris said:
RJP Electric said:
Type AC is the new BX with the bonding strip called Armored Cable. The old stuff is not classified by the NEC.

I just checked some old electric history books. The classification of AC (armored cable) for Greenfield's invention was fomally adopted by the NEC in 1932. This was the stuf the some people have called BX after the General Electric brand name.

The bonding wire that was later added became a requirement under NEC code in 1959. Still called AC.


Slow day? :coolsmile:
 
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