11 votes

Metal clad cable: are there any useful residential applications?

Places where you'd rather not have the NM cable nibbled on by rodents. Having seen enough stripped-to-the-copper NM in remodeling, I'm not a fan of the stuff, given that "There are no mice in my ...
Ecnerwal's user avatar
  • 212k
11 votes

How do I wire to NEC code my detached garage?

Subpanel rating >= feeder wire rating >= supply circuit breaker Tires come in several speed ratings. 85 MPH, 112 MPH and 130 MPH. Subpanels come in 70A, 100A, 125A and 225A. It's only a "...
Harper - Reinstate Monica's user avatar
11 votes
Accepted

What is the correct way to wire a Relay In Box (or similar relay) that has low-voltage signal wires bundled with 120V wires?

You're on the right track. The same manufacturer (and others) make similar relays where the low and high voltage wires come out opposite sides of the device, with either the high voltage or low ...
jay613's user avatar
  • 37.4k
10 votes
Accepted

Can I wire my infrared heating panels to my existing circuits?

TL;DR Only # 1 is legal. The first 15A circuit should be OK. The number to use is actually 12A/1,440W (often referred to as 1500W based on 125V). That's because lighting and these panels are ...
manassehkatz-Moving 2 Codidact's user avatar
10 votes
Accepted

Am I allowed to place a light in my small closet per NEC 2023?

You can't put a lampholder in there (like you have right now) - not nearly enough clearance. But you can put in an LED. From 410.16: 150 mm (6 in.) for recessed incandescent or LED luminaires with a ...
manassehkatz-Moving 2 Codidact's user avatar
8 votes
Accepted

How and when must I satisfy NEC 2020 requirements for outdoor disconnect?

Wait. You're planning To DIY a main panel replacement??? And you don't like meter-mains? That doesn't make any -- um, just read on. TLDR: don't merely get a meter-main, get a Ranch Panel and a nice ...
Harper - Reinstate Monica's user avatar
7 votes
Accepted

Do I really need to run so many parallel EMTs?

Welcome to your electrical education. You more or less have it right, other than your horror at what you've learned. There is an exception for conduit nipples less than 24" long which is ...
Ecnerwal's user avatar
  • 212k
7 votes
Accepted

NEC gurus: What does condition 2 mean in the exception to subsection 250.32(B)(1), to not run an equipment ground in a feeder to an out building?

I'm trying to understand the exception in the NEC, subsection 250.32(B)(1), which gives permission to use the NEUTRAL (in NEC lawyer-speak: "grounded conductor") as the ground fault current ...
Harper - Reinstate Monica's user avatar
7 votes
Accepted

Does no-receptacle on >50% hardwired loads rule also apply for dedicated receptacles?

The problem is you're considering "receptacle + USB". But you only actually want to use the USB, and the problem is the receptacle part. Hopefully no space heaters, but who knows - maybe the ...
manassehkatz-Moving 2 Codidact's user avatar
7 votes

Am I allowed to place a light in my small closet per NEC 2023?

You might have missed 410.16(D) exception [ formerly 410.16(C)(5) ] Surface-mounted fluorescent or LED luminaires shall be permitted to be installed within the clothes closet storage space where ...
Ecnerwal's user avatar
  • 212k
6 votes

How can circuits be prioritized depending on real time demand?

There are EV systems that will reduce the available current the car is allowed to pull based on the load on the rest of the house. They way they do that is by monitoring current probes on the feeders ...
ratchet freak's user avatar
5 votes

Temp rating and insulation type of old nm sheathed cable

In 1965, NEC 1966 had yet to be adopted, and grounded wiring to 240V appliances was not in the code yet. As such there's no (historic) code violation if those aren't grounded. Even in 1966 grounding ...
Harper - Reinstate Monica's user avatar
4 votes
Accepted

Do I need to separate my main and gas grounding conductors?

It doesn't really matter if the wires contact each other. What matters is they are not cut and spliced anywhere they're not allowed to be, e.g. anywhere along the Grounding Electrode Conductor. The ...
Harper - Reinstate Monica's user avatar
4 votes

Above ground (outdoor) UF-B cable and Conduit

As a practical consideration it should be avoided because it's a PITA to pull through PVC, you must use larger conduit than expected, strange securing rules apply, but not completely prohibited. You ...
NoSparksPlease's user avatar
4 votes
Accepted

1 gang box fill capacity/size for receptacal and two 12/2 Romex & pigtales

Any box at minimum size for wire fill IS really tight. Normally we choose to avoid it, but if you need to go there for practical reasons other than easy installation, you appear to have the math ...
Ecnerwal's user avatar
  • 212k
4 votes

Is it OK to bond an electrical box with 14ga wire if it also contains 12ga wire?

The grounding conductor needs to be suitable for the largest circuit in the box. A circuit "just passing through" is still in the box. You only need one ground, but it must be suitable for ...
Ecnerwal's user avatar
  • 212k
4 votes
Accepted

2020 NEC: Proper installation of PVC Conduit for Data Cables

While it's unlikely that your LAHJ will specifically inspect your LV cabling, it's prudent to follow code regardless. Code is, at its root, about saving lives, mostly from fires, (the body that ...
Ecnerwal's user avatar
  • 212k
4 votes
Accepted

splice ground wires together in conduit bodies

So, if the conduit body is not marked by its maker with a volume, you can't splice in it at all. If it is marked with a volume, you have to meet box fill to splice in it. (Article 314.16(C)(2)) (...
Ecnerwal's user avatar
  • 212k
4 votes

Cabling electric cable (AWG 8) through roof of garage; NEC code?

Electric code doesn't really care about holes in the roof .vs. holes in the wall. Service masts that penetrate roofs are very common. Common sense says not creating a potential roof leak (& flat ...
Ecnerwal's user avatar
  • 212k
4 votes
Accepted

Can I use a main breaker as an “occasional” disconnect switch?

There are two ways a breaker (main or branch) can be used as a "switch". Occasional For this, any breaker will work just fine. There are plenty of times where the main breaker on a panel (...
manassehkatz-Moving 2 Codidact's user avatar
3 votes

How can circuits be prioritized depending on real time demand?

Part 1: EVs The idea being that the system will keep me from overloading the 125a service by switching off power to the EV circuit if the backyard appliances are on. I find it interesting that you'...
Harper - Reinstate Monica's user avatar
3 votes
Accepted

Can I cover a junction box on an unused circuit with an oven in a cabinet?

The answer will depend on whether or not the outlet you're covering up was in the middle of a line of devices, or at the end. If the outlet box was at the end of a line (i.e. there is only one cable ...
Chris O's user avatar
  • 6,785
3 votes
Accepted

EMT fill capacity and derates mixing 14ga & 12ga

Deal with grounds. Properly installed EMT provides its own grounding and does not need a ground wire. So ground wires in those conduit segments should be deleted altogether. Where ground is required,...
Harper - Reinstate Monica's user avatar
3 votes

Is it OK to bond an electrical box with 14ga wire if it also contains 12ga wire?

Sharing the ground is fine as long as the ground is big enough for all circuits. If this is a plastic box, then you don't need to worry about the 12 AWG wires shorting against the box. If this is a ...
Harper - Reinstate Monica's user avatar
3 votes

Bonding at Meter vs. Main Panels

Leave the bonding jumper screws in at both panels. NEC 250.24 provides the delineating line about where and how the required service bonding is done ahead of the service disconnect, and prohibiting ...
NoSparksPlease's user avatar
3 votes

Is it to code to have two SPST switches to independently power a single load?

Your problem is your wiring, not the idea as a whole. Paralleling two SPST switching devices is fine under the Code. However, the problem is you are routing the wiring in a way that violates the NEC ...
ThreePhaseEel's user avatar
3 votes

Is it to code to have two SPST switches to independently power a single load?

You cannot do what you drew, but I don't think you need or want to do it that way. You just want the functionality right? You want a humidistat to power the fan with a manual override to force the ...
jay613's user avatar
  • 37.4k
3 votes
Accepted

24VDC along side 120VAC Romex?

This is not a constraint per se, but more of a "keep your future options open" strategy. If you'll run the DC wiring using ordinary AC wiring methods (NM/B "Romex" cable, junction ...
Greg Hill's user avatar
  • 30.6k
3 votes

Does Kitchen's 2' Outlet Spacing Apply if Counter is Beneath Window?

The sink area itself is excluded. Measure 2' from each edge of the sink, and you need a receptacle within that space. Note that the rule is not "1 receptacle for every 2' of counter", it is &...
manassehkatz-Moving 2 Codidact's user avatar
3 votes

Routing ground bonding conductor across garage

Well, I looked over the NEC 250.64 and surrounding sections pretty carefully. There’s no indication that running a GEC through walls or even above a garage ceiling would not provide the necessary ...
D.Mac's user avatar
  • 93

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