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23

For an old installation, there are some "shortcuts" grandfathered in, but even those are based on "no ground but have a neutral". You have the opposite - and much worse - problem of "no neutral but have a ground". Rip out the 8/2 and put 8/3 in place. That will give you two hots (typically black & red), neutral (white) and ground (bare or green). ...


11

You can't do that. It'll fry your equipment. What you have is 240V "wild leg delta" (orange phase). This is 240V delta with a neutral point inserted halfway between red and black phases. It is 240V specifically, so it will be 120V from neutral to red and black hots, and 208V from neutral to orange hot. This gives it compatibility with 120/240V split ...


9

You can't do that. That's been outlawed since 1989. You need to redo the circuit using 8/3 cable (or 6/3 if you aim to breaker it for 50A). You need to wire a separate neutral/ground and bring it into a NEMA 14-50 receptacle (if you use receptacles, that's not required). You also need to jumper the oven for a 4-wire connection, which means removing a ...


8

If you're building a new building and having new HVAC installed, I would simply put 1/2" conduit in the wall and be done. That way, you let the installer run the wire they need. I don't know that I would do this without at least consulting an HVAC installer to see where they would put the unit and the air return (typically the thermostat is as near the ...


6

The difference between the L15 and L21 series receptacles is the presence of a neutral wire, not a ground wire -- both types have a ground. The L21 series is intended for 3-phase Wye 120V/208V, whereas the L15 series is intended for three phase (either wye or delta) at up to 250V, where a neutral is not present or needed. If your current L15 plugs are ...


4

That choice of copper wire is going to be even more expensive when the inspector makes you rip it out and replace it with the 3-3-3-5 you should be using. You need to use the 75C column in 310.15b16 and can't use the 83% bonus derate on subpanels. There's an urban myth that 4Cu/2Al is allowable on 100A, that was due to a misunderstanding of the ...


4

Get a PK7GTA and clean this mess up Your panel appears to be a Square-D QO612L100RB (of unknown series, though). The correct grounding bar for your panel is a Square-D PK7GTA; this should be pretty easy to find at any electrical supply house that carries the Square-D product line, and shouldn't cost more than $10. With the feeder breaker off, you'll need ...


4

You are correct in your assumption that your neutral and grounding conductor must be separated in subpanels per the NEC which only allows neutrals and grounds to be attached on the same bus in the Main Panel with a main circuit breaker. You or a contractor should go out and purchase a second bus and separate the conductors. I can also say that your ...


4

Yes, you should fix it. If nothing else, if you crossed the wires, the threads of the socket would be hot, even with the switch off. This would give a good chance of shock when changing the bulb if you’re not careful.


4

If your splices are failing, that is a technique problem. A competent wire-nut splice should be reliable. It doesn't matter legally, you can either leave zero spare length, 18" of spare length so you can splice to it if needed, or actually fit a splice. You always have the option of running a replacement wire if needed since it's conduit -- that's why it'...


3

This is kind of a tricky question. For many years contractors connected the disposal and dishwasher on a split receptacle below the sink. Now with newer and larger appliances consuming more power there could be a problem. Also there has been some conversations in the AHJ and Code communities about NEC 400.12 (2) Uses not permitted - Where running through ...


3

For traditional Heat + Fan + AC systems, you need 4 for the system to work at all, and 5 if you want to support the C wire for smart 'stats. However when you get into heat pump and multistage systems, just throw an 8 in there - it's readily available and not that much more expensive. You're not going to get very many latté's with the cost savings from ...


3

I'd leave loops of everything except the travelers in each box, especially if the incoming was at the light, where power would have to be brought through all of them anyway. That's assuming there isn't a junction box in the middle somewhere that might someday be a 4-way; then you'd need the travelers too. Fishing a fifth wire down an EMT with four wires in ...


3

To me the choices are equally acceptable. I don't see either as a good or bad practice. As long as a good splice is made it will last indefinitely. And sometimes I like less clutter in the box.


2

Given that it serves a pool area, you really, really, really want GFCI protection: it's cheap liability insurance. That can be either as a 2-pole GFCI feed breaker in the main panel replacing this with a "hot tub" subpanel that includes a GFCI main (but finding a 6-8 space hot tub panel will be hard), or GFCI breakers in each slot (which will preclude use ...


2

Unhook all 4 conductors. Identify 2 conductors that are in the same cable. Necessarily, one will be white and the other red. This pair will be a pair of travelers. While we're here, it's illegal to use a white wire this way without marking it with black or a color. Also, nothing tells you that this white is associated with that red. I suggest marking ...


2

The simple answer is to connect your new switch in an electrically equivalent way -- pigtail the two reds together and attach it to the screw. This will guarantee the switch functions exactly as it does now. If instead you want to disconnect one of the red wires, you need to figure out where they go. It's possible that they're actually the hot wires and ...


2

You are using individual wires, so you need conduit all the way if you don't want a box Since you are using individual 4AWG THHN wires (instead of some sort of cable), you will need to run in conduit all the way from one panel to the other, unless you wish to have a box somewhere inside the house where you transition from the conduit wiring method to some ...


2

It's unlikely anyone makes or carries such a thing in copper. By the time you get to cables this big, most people are going SER. Your best bet is to buy 4 gauge THHN and bury it in conduit (can't be direct buried). Not only is that a lot easier to find, it gives you exactly what you're looking for.


1

Electric ranges use a three wire 220v/110v circuit with a neutral wire splitting the voltages between the hot legs. There is also supposed to be an earth ground, which is a fourth wire. The old code allowed the ground wire to be omitted, but that is ancient history. Not acceptable for new work. Pulling 8/2 wire was incorrect. Wiring the bare copper ...


1

The wiring that is run through the house and for that matter that through the new garage, as long as it is free from physical damage, as stated earlier, does not need to be in conduit. However, it does need to be in a cable assembly as in NMB, SER, etc. The wires, at a minimum, must be enclosed in a protective thermo plastic jacket. Junction boxes are ...


1

Yes, it's essential because you could have wired the fixture as a switched neutral instead of a switched hot... This is deadly! Turning the fixture "off" would not truly switch the hot conductor off and you could get electrocuted with the switch in the "off" position.


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