53

After writing out the question, I realized I had forgotten to check something. I went back to the panel to see if any other breakers besides the dryer circuit had flipped off, and sure enough, the "garage light" breaker had been tripped. After testing more, I determined that the smoke detectors are actually on the "garage light" circuit ...


34

Could be an unmarked Multi-Wire Branch Circuit We often look at people's panels for other reasons, and we often say "hey, see the red+black wires from the same cable, going to 2 independent breakers? Those need a handle-tie. So when you shut one off for maintenance, they both shut off". And people say "thanks" but think "why ...


19

Absolutely could be the cause. A hole in the cable could cause an intermittent short depending on rain, rodents, etc. That can draw so much current so fast that it can trip both the feed breaker and the main breaker. There are rules for how deep wires or cable need to be buried, to avoid these types of problems. Simple cable has to be buried the deepest, ...


13

Oh boy...whoever did that work really botched it up good You need to call whoever rearranged those breakers back and tell them to fix their messed-up work on their dime, or better yet, pay someone competent of your choice to fix their errors. What they did took a perfectly fine panel configuration with spare slots in it and likely damaged it, atop ...


12

Allow me to color in ThreePhaseEel's superb answer. First, you need to understand how panel busing works. Check that link for the basics, however, the tandem/quadplex concept does not apply to GE -- the water heater breaker is NOT a tandem (note the handles are not independent!) Effectively, GE gives you 1/2" wide breakers and you "build your own&...


6

A feeder is breaker and wiring that supplies a subpanel. A branch circuit is breaker and wiring that supplies various outlets, including receptacle outlets. "Outlets" does include hardwired loads, or as they like to call them, "utilization equipment". Wiring can be one or the other, not both. You cannot have outlets on a feeder. So no. ...


5

Table 220.55 and combining appliances Since you're replacing a range with a cooktop+oven as separates, we start with NEC Table 220.55 Note 4: Branch-Circuit Load. It shall be permissible to calculate the branch-circuit load for one range in accordance with Table 220.55. The branch-circuit load for one wall-mounted oven or one counter-mounted cooking unit ...


5

This is easy to diagnose. If you are comfortable working in a live panel, take off the cover plate and remove the black wire from the troublesome breaker, to be doubly safe, you might want to turn off the main breaker first. Once you've removed the wire, turn the main breaker back on and try to reset the breaker, if it trips or won't reset it's dead. If it ...


4

Eaton CH This is an (old) Eaton CH breaker -- the tan handle, hook-on-end mounting clips, and jaw system are quite similar to what you'd find on a current-production CH breaker, even.


4

Evict the alien! That Siemens QT quadplex breaker has absolutely no place in your Eaton/C-H BR panel. As a result, the correct replacement is a BR quadruplex breaker, namely the BQC215215, which should be available through your local hardware or big-box store.


3

First of all, a dryer receptacle is rated 30 amps, not 40, so if it's on a 40 amp breaker, you're already in violation. If you truly have a 40 amp circuit (#8 copper wire minimum) the you're ok for the wires being on a 40 amp breaker but not the receptacle. If you have #10 copper on a 40 amp breaker then you are overfused. Either way, there is nothing wrong ...


3

The question is different but the answer is exactly the same. This breaker does not provide any location to attach the wires from the SPD. The only difference is this is a discrete main breaker, not a meter-main, so it will be a great deal easier exchanging this unit for one that does what you want. That being a main-breaker service panel with thru lugs (...


3

The feeder cable to your guest house is required to be guarded by stout conduit all the way down to 24” burial depth.* If you can see the wire, then the installation was a hillbilly job from the day it was installed, or has failed catastrophically i.e. by being hit with a dump truck. The main breaker trip is not a surprise given the critical damage to the ...


2

You have a Multi-Wire Branch Circuit or MWBC. I put one of these wires, we will say the red one, into the empty 15A breaker. The only problem is since they share the same cable I don't have a second neutral to wire into the back of the newly occupied breaker so everytime I turn the fan on in the room now powered by the red wire the breaker trips. Yup, and ...


2

Any circuits fed off a GFCI or RCD device must have total monogamy between live and neutral wires. Any load served by the hot must be served by the neutral. And vice versa. Some amateurs are in the habit of "borrowing neutral" from any old circuit that happens to be nearby. Their logic being that neutral is like the chassis on a car with car ...


2

You need a different transfer switch Not only does your current transfer switch require a degree of finagling to work with multi-wire branch circuits, it can't be used with your generator even when MWBCs aren't an issue! This is because "select circuit" transfer switches only have a single neutral connection lead and no neutral switching, but your ...


2

I had a landscaper hit the power line to my shed with his trencher (more accurately his assistants). It didn't pop the breaker in the subpanel it runs from, it popped the subpanel breaker in the main panel. As manassehkatz suggests, I went with conduit and ran new THHN-2 (THWN-2), which you cannot direct bury. THHN is likely going to be cheaper than ...


1

Done. Main shutoff plus Generator input with interlock plus Whole house SPD. First Surge is rated Nema 3 I think, but even instructions say if weather an issue, to enclose. So the clear box is nema 4


1

Transfer switch: can't do it. See the red wire at "H"? *It is half of a multi-wire branch circuit (MWBC) - 2 hots sharing a neutral. You cannot use this type of transfer switch with MWBCs, unless the transfer switch has both of them on a tied breaker (one intended for 240V). I can't even see where the MWBC partner black wire even is. It might be ...


1

You can do that, but there's no particular reason to think that it will work correctly, since the neutral current does not know which breaker it should go back to. That certainly would be expected to fail with two separate GFCIs, I don't know how much AFCI's look at differential currents. Use a two-pole 15A breaker (assuming you have 14Ga wire somewhere in ...


1

The first rule of GFCIs You have connected the GFCI's neutral pigtail to the neutral bar correctly. The only thing that can explain several GFCIs failing in every iteration of your rather exhaustive testing - is also one thing you did not mention. The first rule is: All hot and neutral current MUST come through the GFCI device. Because, the basic function ...


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