19

Did you shock yourself? Most likely not. The plastic handle of the scissors, though not rated or approved by any regulatory test lab for cutting live wires, is likely to have protected you. There's also a fair chance that your body wasn't in contact with any grounded conductor, so even if you did come in contact with the live wire, you would not have been ...


19

The evidence would suggest that it is an improperly wired multi-wire branch circuit. The two legs of the circuit are erroneously and dangerously shorted together somewhere. When a MWBC is properly wired, the only path from one leg to the other is through the loads. The reason the two breakers are on the same pole is some delirious spark monkey discovered ...


12

You can, but you need a 3/4" KO and the correct clamp to do so If you're working with a 3/4" or larger knockout, you can get 3 12/2 or 12/3 NM cables into it. You just need a cable clamp that's listed/rated for that many cables; fortunately, the Arlington NM842 is cheap and fits the bill perfectly here. It can even accept 4 12/2, or 2 12/3 and 1 ...


11

Just to be clear it sounds like turning on either of these breakers energizes the receptacles, if this is correct then you should leave one off until you correct the actual problem. Actually you should leave one breaker off until resolved even if they aren't joined, having both of those on the same leg you could get 40 amps on the "neutral" without ...


10

That's a common complaint. Every maker's filler plates are a) flimsy, b) expensive, and c) hard to find. Fortunately, Square D also sells a much more robust filler plate which solves all these problems, called the QO120. They're sold everywhere, latch onto bus stabs, and aesthetically look - well, they actually are breakers! I'm not joking. "Actual ...


8

No. The breakers have no effect whatsoever on the panel load calculation. Because load calculations do not work that way. Load calculations are based on house square footage and major electrical appliances. Adding a Tesla EVSE has an effect. Adding an addition has an effect. Fewer vs more receptacle/lighting branch circuits has no effect. Think about it. ...


8

Generally, if you have spaces broken out in the deadfront, you also have breakers that filled those spaces. You can leave the breaker(s) in place, connected to nothing, preferably labeled as such, if you have reconfigured the panel to no longer need those breakers at present. They store just as well there as on a shelf, and are harder to lose.


8

You need to de-energize the wiring I realize you're very cocksure, but... Really, really, you need to de-energize the wiring using the normal methods for doing that in your country. Absolutely no one on this forum is going to counsel you to do that work "live", even with the much more docile American 120V-to-ground (2 or 3 phases). Here are the ...


7

Since you have QO...there's a third way :) If you find filler plates too flimsy/awkward, and putting a regular breaker there too error-prone, Square-D has you covered too! Simply get a QO1DB dummy breaker (or three) and use it in place of the filler plate. (These clip to the busbar just like a regular QO, but can be identified by their utter lack of a ...


7

The panel may look identical to you but the thickness of the buss and the material makes a big difference where a inch of copper can handle 1000 amps per square inch verses aluminum of only 700 amps (NEC 366.23) so the buss material makes a difference it may look the same even be the same thickness but one being solid copper and one being aluminum with a ...


6

TLDR: Square D makes a 2-pole CAFCI (# QO220CAFIC) that will do what you want. However, this panel needs a lot more attention, as it has more "bomb" circuits like this one, and it's full, and addressing that will intersect with this issue. It's called a Multi-wire Branch Circuit. There's nothing wrong with them. You're just a) unfamiliar with ...


6

I can answer at least part of this, I asked Square D and they said: Unfortunately, we just offer a single filler plates for branch breakers, QOFP like you mentioned or if this one old load center maybe you will need a QO1FP filler plate for each space, I recommend you install one per space, below is the link with a video and the installation bulletin. FAQ ...


6

PKSB1HA will definitely not fit a QOC 40MW225 panel, and probably not any QOC series panel. They have an FAQ which says: Does Schneider Electric offer repair parts for the Old(25+years) QO Load centers? (For example old QO--MG200_ _ , QO--MW200_ _ or QOBW3150-1) No, the older 25+ years or so QO load centers are all obsolete, with no repair parts available. ...


6

Clamps/fittings need to be NRTL (UL/ETL) Listed, and the instructions on or with the fittings are part of the Listing, and will indicate the number and type of cables allowed.


6

There's a concept called grandfathering which says If the work was legal on the day it was installed, then when Code changes later, it's still legal. You're not required to tear out a bunch of wiring every 3 years when Code is revised. This gets into a lot of lawyering about when the work was done and what was legal then. However we can safely pass ...


5

Having the neutral cross the hot bus is not a code violation. However since neutrals are not protected for overcurrent, if for some reason a second circuit was tied in and the insulation melted it could damage the panel badly enough to require replacement. I have seen this. I would route the wire around as not to create this remote but possible hazard. But ...


5

The isolated bar is intended for Neutral. If, like many generators, yours has ground and neutral bonded inside the generator, your generator neutral and all neutral wires go to the isolated bar, and the ground wires go to the one connected to the box. That also sets you up properly for a "shore power" input. Your hot feed either goes to one of the ...


4

You're asking about the Dielectric strength of air. Among other things, it depends on the shape of the electrodes (the bare wires) and contaminants in the air (humidity, dust, etc). We can't give a precise answer - but at 400V the distance is quite small. If you can see a gap between the conductors then it's big enough that an arc won't form. Until an ...


3

It can go either way. often the feed to a panel goes "backwards" through the main breaker (compared to the other breakers).


3

You can breaker down but not up, so yes, you can just replace the 60 with a 50, the wires should fit. Before you do that though, check with the installation instructions to verify what your plumber wants you to do. The instructions will specify what size breaker you need to have and changing those directions can void any warranties you might have.


3

I'd pick two of those 20s and swap them for a 20-50-50-20 triplex breaker Since your panel is listed and labeled to accept tandem/"double stuff" breakers in all positions, and looks to be uniformly configured with 20A breakers, we can take two adjacent 20A breakers in the panel and switch them out for a MP22050CT (if you can find it) or Q22050CT (...


3

An alternative (better than nothing since they don't make a part to do it nicely) is to apply good quality electrical tape (not some off-brand that falls off after a few months) very carefully to cover the service lugs (not touching them, but taped over the the black plastic wings around them.) Personal bias - pick a bright color, not black. Black blends ...


3

This isn't an issue because you're dealing with an EGC As it turns out, while using a stranded wire would have pulled more easily, you are in the clear with regards to your solid 8AWG copper equipment grounding conductor Code-wise. This is because NEC 310.106(C) (i.e. where your NEC 310.3 cite moved to in newer NEC editions) yields to other parts of the ...


3

To add to what Ed has said... Installing an accessory ground bar and landing it there is not an option because neutral is not ground. I understand why you think that... but consider what you are looking at. Here's the thing. Grounds never carry current except during fault conditions, which are supposed to be momentary. Neutrals carry service current ...


3

In that pico-panel, you have a major defect. You have the breakers incorrectly swapped. You have a 40A breaker on the thin wire and a 20A breaker on the thick wire. The thin wire is totally unprotected. Swap those breakers! You are correct. Without a neutral, that pico-panel cannot support any 120V loads end of subject. You cannot use UF-B as extension ...


3

When the building was built code was probably 3 wire ( this was the standard for decades). What you have was quite common until the1999 NEC code change. A 200 amp feed would normally be in conduit and if metallic that could be used to meet today’s code. If it is a direct buried feeder and you feel the need to update it a separate ground wire is now allowed, ...


3

A 125A "main breaker" in the subpanel is fine. However, the breaker feeding this, which is in the main panel, must be 80A or 90A depending on the insulation of your wire. Actually, I'd recommend a "larger" subpanel than 125A. The thing you really want is spaces, because a 90A subpanel can support a whole lot more circuits than you think ...


3

Like Ecnerwal says, you lost a phase. 99% of the time this is the power company's problem, and they come out and fix it for free. Simply report an outage. But why aren't half my circuits dead? Because the two phases are shorted together. OK it's not a dead-short, it's a low-resistance short. If the power were working normally, this thing would be making ...


3

The instructions are CSA-approved (or UL-approved; UL is now licensed to approve in Canada thanks to trade deals like NAFTA and GATT, thanks Bill Clinton). They are requirements and must be followed, unless you obtain an AHJ waiver. The reason the UL-approved instructions require at least a 125A service is because a 100A service would not leave enough ...


3

You're going to need to unmount this box and move it forward slightly, because there's no other way out of this situation The root cause of your issues is that the drywall was inserted as an (improper) "shim" to work around the fact that your breaker panel was mounted too deeply into the wall. You see, not only does the current situation violate ...


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