118

Call the power company back. You lost a pole. Here's how your house normally works. Here's what happens when a hot wire breaks. That's simple enough, right? Half the 120V loads croak. And all the 240V loads... right? But wait. What if they are both on? Say that water heater cycles on. This. This is why the electrician and the power company read ...


73

It's a temperature sensor w/ wireless transmitter: https://www.inovonics.com/products/dual-input-temperature-transmitter-en1723/ I found that by googling the various numbers printed on the stickers -- EN1723 turned the device up as the top hit.


63

Turn off 120V appliances NOW. Call the power company and report an outage. What you have is a classical "Lost Neutral". The dead giveaway is when circuits teeter-totter: when one pole's voltage goes down and the other one's goes up. This is the most dangerous type of power outage. If you lose a hot wire, half your circuits go dead until a 240V appliance ...


56

It starts with spaces in the panel A service panel has a basic unit I call a space. That's apparent when you look at the "knockouts" on the cover. Electrical power in North America delivers split-phase power. Meaning there are two "legs" or "poles" - L1 and L2 - both 120V from neutral, and opposite-phased so they add up to 240V. Here's an X-ray of a ...


55

Concurring mostly with Some Guy's answer here -- the reason why I take an aggressive tone in my other answers regarding FPE is because many of the OPs are coming to us because they want to do something to the breaker box, such as adding a new circuit or replacing a breaker that "died". Note also that all of this advice applies to panels labeled &...


54

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 ...


46

Call the power company NOW and report a power outage The fact that you've worked on your panel is unrelated. Given the testing you just did and the results you got -- you have a power outage at the meter pan or before. It could be where the neutral service wire connects to your neutral bar, but that's the only place it could be on your side, and super ...


45

Defective receptacle. Kill it with fire, before it kills you with fire. And if it has backstab connections (wires jabbed in back holes that auto-grab them) this is a good time to get rid of em. Because they cause this kind of mischief too.


45

Phase/Leg Out You have lost one phase or leg (terms vary) of your power. 120/240 power comes in on 3 wires - two hots each 120V from the neutral and 240V from each other. Most breaker panels are designed with alternating legs. Left & right in each row are on the same leg. 240V (dryer, oven, A/C, etc.) use a pair of breakers, one on each leg. Your ...


44

Your "electrician" is not one of the brighter bulbs in the pack. The 40A is to protect the wiring and the device. If the wiring is AT LEAST 8Ga then it's adequate to protect the wiring. It also protects 6Ga, (or 500 MCM for that matter) just fine, and it properly protects the device at the end of the wire just fine. "Ohms law" has squat to do with this. ...


42

Ed Beal's post covers a major point... here's a little backgrounder on that. A 20A breaker @ 120V will supply 2400 watts nominal. "Sounds like plenty, what could 2 bathrooms possibly use?" Well, one hair dryer is between 1500 and 1800 watts. So while it's perfectly legal for any number of bathrooms to share 1 electrical circuit (one McMansion was ...


39

Why bury a cable when you can be future-proof? The primary issue with direct buried cables is that you have to dig them up in order to upgrade them, a costly proposition. Hence, it's a far better choice to spend the money to lay a couple of fat PVC conduits now and then pull wires through them, than to have to dig things up 5 years down the road because ...


39

Since the wire is 14/2, the breaker feeding it must be 15A. Someone apparently changed that to a 20A breaker (presumably because they were sick of constant breaker trips every time they attempted to use two heat appliances at once). Since that was done, you have the sense of "hey, do it even more". That "end justifies the means" POV ...


38

Was the bozo that wired those circuits trying to burn your house down? Assuming that the wires are 10AWG (i.e. 30A), this is a major problem indeed as the wires can overheat badly from excessive current draw before the breaker ever notices something is wrong! Think of what a live toaster element inserted into your wall would do... As to the Code, your ...


38

I think you have likely answered your own question. The use of an extension cord could cause a voltage drop, especially since the factory cord is long already and the spa probably has an electric motor that would be damaged by voltage drop. Also, cord/plug connections are not weatherproof. This is a CYA (cover-your-arse) by the manufacturer. Your plan of ...


35

You should call the utility company. You likely have an open circuit between the neutral bus bar on your electric panel and the neutral wire that goes to the meter, or further upstream. Split-phase power usually works like this in the USA and Canada: The transformer's secondary is 220V-240V, and it is tapped in the middle to produce 120V between the center ...


35

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 ...


31

The problem is that all of those outlets and fixtures are on a single circuit. That means a single cable. The circuit breaker is merely the beginning of that circuit run. What you need is more wire, not just more breakers. You would have to run a separate wire from one or more of those outlets and fixtures to the panel box, and then you could add a new ...


31

Call your utility and report a power outage It's not random -- you've lost a phase. Every other breaker in your panel is on opposite phases of 120V, and 240V breakers grab both. The pattern you are showing means that one of those phases is working fine, and the other one is intermittently dead. See the images in Harper's answer here if you want all the ...


31

Your electrician was thinking further ahead than you thought they were As it turns out, your electrician did think of powering outbuildings when they put your 400A service in, after all. The cheapest way to do a 400A service is to use a Class 320 socket feeding two 200A main panels; however, your setup is a bit more sophisticated and flexible, and that's a ...


30

There is something you can do: Do not turn on both appliances at the same time! This is relatively straightforward for the combination of a heater and toaster. Unless you are a toast making factory, the toaster runs like 3 minutes per day. During that time, turn off the heater.


30

The basic reason is that if they said, "Feel free to use an extension cord", someone would connect up a 50m, 3A, two-core cable with no Earth and a loose socket. They would then sue the company when it didn't work (too much voltage drop across long thin extension cables) or it caught fire (current drawn exceeds capability of thin extension cables) or they ...


30

Grats on your successful generator test :) Whenever you have a bolted fault, you flow hundreds of amps. The only thing that impedes flow is the resistance of the wires themselves, which you can look up on the internet. "Hundreds of amps" is well within the range of the "instant trip" functionality of every breaker in the panel except ...


29

If you truly want to future proof, install conduit instead of cable. This will allow you to pull whatever wire you need, once you've decided what you want. 3/4" conduit should work fine, and would give you the option to install up to four 8 AWG condcutors (Schedule 80 PVC). If you think you'd ever upgrade to a whole house unit, this might be a good option....


29

The breaker needs to be sized to protect the wire and the device. Wire Larger wire (which is a lower # due to the way wire sizes are named) can use a larger breaker. But a smaller breaker is always safe. 55A is the largest breaker you can normally use for 6 AWG copper. 40A is the largest breaker you can normally use for 8 AWG copper. But you can always use a ...


28

Not in your lifetime. Nah, it's cool. Eaton has owned Cutler Hammer since 1978. Alien breakers require immediate attention! BRLAFGF115 and BRLAFGF120 are fine. This looks like a Cutler Hammer "BR" 40-space panel that is full. The panel is perfect. Mergers & acquisitions are normal in that business. Eaton just chose to acquire Cutler-Hammer, instead ...


27

This is a breaker lockoff device The gizmo on your water heater breaker is a lockoff that's designed to let you turn the breaker off, then attach a padlock with a 1/4" shackle (or a lockout tag with padlock(s) on it), so that you can then lock the padlock, stick the key in your pocket, and be sure that some bozo isn't going to flip the breaker back on ...


26

Oh dear. This is a foogly mess. First, you did the right thing by punching that main panel breaker down onto a single. The problem is with the subpanel; it is very badly misconfigured by a guy who cut a lot of shortcuts. First, it is illegal to double-tap neutral bar screws like that, unless the panel's labeling or instructions say they are intended ...


26

It ain't about the handle-tie Common trip does NOT work by one handle tripping, and that action dragging the other handle over via the handle-tie. That is not how that works. That wouldn't work because the handles "trip free" - that is, if the breaker needs to trip and a padlock or naughty human is impeding the handle from moving, the breaker just ...


25

Breakers and fuses are designed to be the weakest parts of the circuitry. It is their feature. Period. They are designed to fail safely. Fuses burn literally, breakers safely discontinue the circuit. If they are oversized, they may not be the weakest points anymore. In case of failure they won't be the first to burn - it may be the most expensive device ...


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