One other reason for not putting a plug on romex is that solid conductors will not tolerate repeated bending - that’s why cords use stranded wire. Aircraft wiring is almost always done with stranded wire as solid wire has been known to break when subjected to vibration. Use solid conductors where the cable will be at least semi-permanently in place.
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Very interesting! I did not know that.
Rich
the purpose using an extension cord is to provide a connection to the layout wiring. Not to repeatedly plug/unplug the layout
perhaps that first box should be larger and have a swtich
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That’s a good point, greg. My current setup, with extension cords under the layout, is semi-permanent, so to speak. The lead extension cord remains plugged in to a switched outlet, so it is never unplugged.
Rich
While I am not an electrician, I have been involved in getting UL blessings for several of the projects that I’ve worked on. It would be safe to assume that most of the UL requirements have been written in blood, with the motivations of preventing fire and electrocution hazards.
One thing UL effectively mandates is use of a plug that’s molded to the power cord. It would be easy to have a box with strain relief for the cord which then allows the stranded conductors of the power cord to be connected to the romex with wire nuts.
One issue with connecting romex to a plug designed for stranded wire is that the solid wire may not have as much contact surface with plug as stranded wire.
Another thing that UL is very picky about is keeping the line voltage wiring separated from the low voltage wiring. Keep in mind that the AC line can have transients of hundreds to thousands of volts.
so i bought a 4x4 box with the cover below to connect the replacement cord to and switch layout so the plug doesn’t to to be pulled
greg, that is the exact box and cover that I use. The toggle switches power to the layout On and Off. The top outlet holds the extension cord and that outlet is switched. The bottom outlet is always live and powers my workbench.
Rich
Good move. I would have used 4x4 boxes everywhere. Easier to wire, look better, safer without screws sticking out the back, easier to mount right thru the back.
Also, the use of romex connectors rather than straps in the box increases the wire fill rating - because the straps count as 1/2 a “wire unit” if I recall. The connectors don’t count because they are outside the box.
Sheldon
@ATLANTIC_CENTRAL
Sheldon, is the purpose of the long screws on the outlets to pull the outlet into the box, compressing the wires?
I’m talking about the screws out the back from the built in wire clamps. Great when the box is concealed in a wall, nasty and easy to rub up against crawling under a layout.
As for the screws on the outlet, yes, more or less, but you should have the wires pre arranged so the compress in easily like an accordion.
Sheldon
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Those long screws should have small square cardboard pieces on the threads to prevent the screws from falling out of the outlet appliance. Very handy in that regard.
Rich
i finsihed wiring my boxes on the layout. Have question for Sheldon @ATLANTIC_CENTRAL
i connected the layout to the wall with a 2 prong plug because the outlet is only a 2 prong outlet, no ground.
i was careful to wire the narrow blade side of the cord to black on the layout plug and it into the hot (right) side of the wall outlet (i verified that it is the hot side)
But i think it needs to be a 3 prong plug and replace the outlet to guarantee that the prong polaritiess are at least correct, that the switch on the outlet does switch the hot side
since i used metal boxes, it would be better if the ground were ground. since all the grounds are connected, a hot wire touching a box would make all the boxes hot, instead of tripping the breaker
however, that outlet has a water pump connected with a 3 to 2 prong adapter. i assume pump housing is wired to it’s ground as well as connected to water pipes which are ground. I believe replacing the outlet with a 3 prong outlet and plugging the 3 prong pump cord into it will provide ground to the outlet.
plugging my layout with a 3 prong plug into the same outlet as the pump should provide a proper ground connection
Greg, first, let’s talk about about this outlet that is only two prong, and your house wiring. How old is the house? Do you know what kind of wiring you have? Romex? What color is it? Are other outlets in the house 3 prong?
Here is the thing, depending on the age of the wiring it is very possible that metal outlet boxes are grounded even though you have two prong outlets.
If that is the case, there are special grounded (three prong) outlets that are approved to ground to the box simply replacing your existing outlet.
Back it the day, early romex had a smaller gauge ground wire, and the approved practice was to ground that wire to the box by wrapping the ground wire around the outer jacket at the point where the cable clamp holds the wire.
The metal strap that holds the outlet in the box, is grounded to the third prong, so simply installing a three prong outlet will ground the third prong if this is the kind of wiring you have. The special approved ones for this process have an extra brass spring tab to insure good contact between the strap, screw and box.
Pictures of your electrical panel, both inside and outside where some of the wires enter, will likely allow me to confirm if your circuits are grounded and just need new outlets.
Sheldon
Greg, reference replies #91 and 92. I understand uprights are 1x1 material (92). But I am curious about #91. I see the cross braces 1/2", the 1x1" support , but what is the 3/4" board? Does the 3/4 go upward for some purpose? As an electrician, I have enjoyed this thread. endmrw0201252217
this part of the house was built in the 60s. all i see is beige romex. all the outlets in the orignal part of the house are 2 pring.
this outlet is behind some wood paneling but must me in a cinder block wall like one in an exposed wall next ot a wood stove.
i’ll have to open up the panel and see if the old house wiring is 2 or 3 conductor
not 1x1i. i found some old 3/4" panels when i moved into the house a few years ago, some solid, others like plywood which i cut down to ~2" and screwed together in an L shape.
I forgot to mention, a quick test in most cases is to check for continuity between the neutral wire and the box. I you have continuity then the boxes are grounded since all that ties together back at the panel.
In the 60’s exactly what I described was standard practice. most likely all you need to do is replace the outlets with three prong versions like these.
Or these,
Both of these are self grounding. I can’t tell if either one has the clamp stye connection which I much prefer. They allow you to put two wires on each screw and the wires just stick straight in under a plate that clamps down. They are approved for two wires on each screw so they are great for boxes that have more the two cables.
Personally Leviton is not my favorite brand, Eaton and Pass & Seymour are much nicer.
Sheldon
Yep, I have a box of those sitting around.
Rich
These are much better, but priced accordingly. They have clamp connections.
Leviton does make them too, but I could not tell from the information on the Home Depot site which one it was.
Virtually all the ones labeled “Prefered” or “Commercial” include the self grounding feature.
Sheldon
don’t understand what you mean “self grounding”, these outlets have the green ground screw. I’ve read that you shouldn’t use a neutral wire as a ground and prefer that it isn’t
i believe the ground screw connects to the metal outlet housing which contacts the box when screwed into the box
in my case, since there’s a water pipe nearby, i’d be happy to connect a copper wire and the screw holding the wall plate to the outlet