Update - Replacing Light Switch with Switch/Receptacle C

Hi, guys. Following up on the thread in the link below. When last we spoke, I needed to figure out how many/what wires are
inside the box for the light switch. I finally peeked today. As you probably can see in the attached pics, there are four
wires coming from the conduit into the box. I suspect they include (a) hot, (b) load, and (c) two neutrals. Seems like
there may not be a ground wire in there:-/

I imagine that the lack of a ground wire would not impede installing the switch/receptacle combo, though I assume it could
compromise safety.

I also looked inside the box for one of my existing receptacles, and I see that does have a ground wire.

Again, welcome any thoughts.

Thanks!

Neil
<img src=https://www.yesterdaystractors.com/cvphotos/cvphoto147344.jpg>

<img src=https://www.yesterdaystractors.com/cvphotos/cvphoto147345.jpg>
Prior Thread






This post was edited by npowell on 02/12/2023 at 07:45 pm.

Take those box screws out and pull that thing out of there so we can see what you got going on there. Nothings going to happen if you have the breaker off.

Really hard to tell unless you remove switch.
I think I see two bare ground wireS in there twisted together. Might be just a bad pic. If that is running inside a metal conduit the conduit is your ground wire. At least that is code here.
Im sure there is a neutral wired together with a mark connector and the love goes to the switch. Switch breaks the live going to the light fixture.

Yea, need to get you a better pic. Will try to tackle that tomorrow. Didn't want to leave the Mrs. in the dark this evening (and I'm not looking forward to resetting the clock on the microwave).

Thanks,

Neil

Don't over think it , just put it back the way it was with the new switch!

I find all this neutral and ground wire comical. Since they both wind up at the same place in the main box fastened to the ground bars in the box then connected to the ground stake in the end. Sure you can try and blow smoke up my with but but they are separate yup right up to the ground bar which has a wire from each going to ultimately the ground stake yes it does go back through the power system. So in the end they are still connected together.

Good morning Caterpillar Guy, as a retired Power Distribution Design Engineer I can happily confirm:

1) YOU ARE RIGHT when you say neutral and ground wind up at the same place in the main box (provided its the main panel (first disconnect).......

2) YOU ARE RIGHT in that typically in the main panel they can be connected to the ground stake.

HOWEVER with all due respect FYI and others who aren't engineers/electricians or know otherwise, let me explain the panels NG Bond. The NEC TYPICALLY requires N and G to be bonded in the main panel BUT NOT THEREAFTER (there shall be ONLY ONE NG BOND). The Equipment GroundING Conductor is to carry FAULT CURRENT ONLY while the Neutral only carries normal return current. With it bonded to N in the main panel if there is a fault it (EGC) provides a low resistance back to the panel to trip the breaker and clear the fault TO SAVE YOUR LIFE

The EGC is often bonded to outer conductive metallic cases of tools and appliances washers dryers toasters etc which you touch.

UNLIKE an often bare EGC Conductor, the Neutral is a hot live current carrying conductor AND IS INSULATED to prevent your contacting it

HOWEVER if N and G are re bonded downstream from the main panels NG bond THE EGC (connected to tools and appliances washers dryers toasters etc) CAN BECOME A HOT LIVE CURRENT CARRYING CONDUCTOR and you can get shocked when you touch it

SOOOOOOOOO yes you are indeed correct NG are bonded in the Main (but not again) for the reasons I noted above BUT EACH SERVES A DIFFERENT PURPOSE and if used correct CAN SAVE A LIFE OR PREVENT A FIRE

Dont take my word for it consult the NEC or any professional engineers or electricians

Best wishes and God Bless I hope this helps you understand the purposes of N and G and why they ARE DIFFERENT FOR DIFFERENT USES........Ground to carry ONLY Fault current (to trip breaker and save a life) ...........Neutral to carry ONLY normal return current..........

Have a great day now post back any questions

PS With all due respect NOOOOOOO my intent is NOT to blow smoke but to help my fellow old tractor lovers, explain things, and maybe even prevent a tragedy !!! Im here to HELP not feud lol

John T Long retired EE but believe this remains true........

Sorry, I still cant tell exactly what's in there.......However a metal junction/switch box REQUIRES CONNECTION TO THE EQUIPMENT GROUNDING CONDUCTOR and if there are Bare/Green wires in there, that's likely ??? the EGC. The Whites are TYPICALLY the Neutral and Blacks typically/often (Hot Line IN Load TO LIGHT out when ON)

Once you get a 120 VAC test light or an AC volt meter just remember

Its 120 VAC from Hot to EITHER N or G

The receptacle requires H N G

Turn off the breaker,,,,,,,,, insure theres NO hot wires in there,,,,,,,,, pull the switch to better see and get to whats in there,,,,,,,,,safely with caution turn on and use meter to see what you have..

HIRE AN ELECTRICIAN if you arent fully safe or know what youre doing

John T

John T, What year were those requirements put out? Could his wireing still being dated earlier before those standards were required and begore a ground wire was thought of.I believe there are older homes still using the wireing from there was only the hot and netrual and no ground. Could his problem be from that wiring the could have been installed back in the 30's, 40's or even the 50's and never updated. I rembeber when the knob and tube wiring was still in use in the 60's. And possibly up to the 90's before the building was torn down. I know the place I was raised in and lived in untill 4 years ago still had wireing installed in 1946 in that had not been updated. I wonder if that is what is making all the confusion.

I dont remember the year when they went to three wire but I cant tell from the pic what wires are there. It may still be grandfathered in ?? He still needs at least a Hot and Neutral for a switch and receptacle. So easy if there were all just trying to help but he sounds so inexperienced prob best we stop and he hire an electrician ?????

Nice chatting with you

JOhn T

Great explanation John T !! I knew the theory was that the neutral conductor carried unbalanced load current back to the panel but until i got jolted good from a neutral conductor i wasn't a real believer until then!
dpendzic PE

A good shock will enlighten a person lol

John T

I agree inexperianced, and if the orignal 2 wire type system it is just confusing him more. I don't know if an electrichion would even be allowed to work on that system or
if would have to tear all the old wire out and change
to the modern style. What I am getting at is everybody is only thinking of the current way to do things forgetting tha he may still have the old 2 wire system and would confuse him even more. So I am going to ask him one question, does his current recptiles have only t2 slots or 2 slots and a round type for third prong on a plug. I am no electrican but I had to learn on the job as Dad bought a farm in 69 and there was only 2 light bulbs in barn and vacant house not much better. Dad hired an electrican to get it ready for milking but he messed things up so bad I had to learn how to straighten his mess up. The older man that owned the local electric supply place with his sons thar were working electricians tought me over the counter how to wire things and that was still the old 2 wire setup. From him I learned the ground wire as well. If he can tell us if other outlets are for a plug with only 2 prongs or more prongs it can tell us more what he is trying to do. I agree not enough information to actually help him.

In the old systems, didn't they use the metal conduit and boxes as the ground, all the way back to the breaker panel ground rod? steve

Thats right Steve, Metallic conduit can be used for the Equipment GroundING Conductor PROVIDED certain applications and all the correct fitting and unions are in place..... In the later years when and where I practiced I NEVER specified that and especially if it was a DIY project absent professional electricians I do NOT advise such. Yes it can work and people can do as they well please far as Im concerned but when my name was on the project I followed NEC guidelines...

John T

Other than the ground, you've probably got everything you need there to do what you want.

While TECHNICALLY not correct, given that the electrical box is connected to a metal conduit which presumably terminates at the breaker box which itself is properly grounded, AND the ground lug on the outlet/switch is electrically connected to its metal mounting tabs... If it were me, I'd just do it. Note that I'm not telling you to do it, or that it is okay. I'm just saying what I would do.

There are threaded holes in the box for a ground tail installation . Box grounded.

np, as is typical when anyone asks an electrical question, sooooooooo many responses may cause you confusion, so FYI here again are the very basics:

NOT knowing whats inside that box..... Hot (may be since it operates the light?? or they may have switched the Neutral ??) ,,,,,Neutral (maybe or maybe not??) Ground (maybe or maybe not) NONE of us are there to know for sure and youre inexperienced SO BE CAREFUL

Under the old two wire system (Hot and Neutral) a 2 pin Receptacle will function if it has a Hot and a Neutral with 120 VAC.......A later 3 terminal receptacle will still function even if it has no Ground....

Under the later three wire system (3 pin grounded receptacles) a later modern 3 terminal receptacle requires a Hot, a Neutral, a Ground.

EITHER can switch the Hot so the light goes on and off WELL DUH that can be so regardless if there's a Ground or Neutral available BUT A NEUTRAL IS NEEDED FOR A RECEPTACLE

I (retired power engineer) would NEVER NEVER NEVER advise a DIY non electrician to rely on the conduit and metal box connections AS AN EQUIPMEMNT GROUNDING CONDUCTOR......While in certain applications metallic conduit and metal boxes given proper connection techniques CAN QUALIFY as an Equipment Grounding Conductor there are so many wrong improper conditions that can cause its failure ITS YOUR LIFE YOUR CHOICE

HOWEVER I support anyones right to do as they well please !!!!!! use the conduit as a ground if you like

Its sounding more like due to your inexperience you might hire an electrician !! If you try to DIY based on whats posted here and get it wrong you could cause a fire or a tragedy !!!!!!!!!!!!

Sooooooo do as you please its NOT rocket science and many DIY no problem all I can do is try to educate you and hope you get it right and safe

Best wishes God Bless you be safe

John T BSEE,JD

I am surprised no one has mentsioned using a GFCI. The last I knew a GFCI can be installed without a grounding conductor as long as it has a label on it stating there is no ground.

My guess about the four wires is you have one with power and three without. The one hot wire is your incoming power which should go to one leg of the switch. Then two of the wires are probably neutral wires, one bonded at the meter going into the box and one going out to the light. The two neutrals should be bonded together at the switch box. Then you should have one wire which should go from the other leg of the switch to the light. Somehow you need to trace which of the wires come from the light.