Which phase is my electrik socket on?

You didn't state that you were running two 120 volt circuits with a common neutral, so do try moving the goalposts.

We were talking about outlet circuits, and as you can see above I wrote, "Not if the breakers go to a 3-wire". I specified breakerS and 3-wire. What other conclusion would or could anyone draw from that?

Thanks, I try ...

I'm sure you're right about that. By the way, my PC is in a study just off the foyer, so that's why it's on the same circuit. I'm going to find out what else might be on it that justified the 30A breaker. What I still don't get is why all my X-10 controls work in the house. They are all on different circuits and phases.

Bud, I checked again what else is on the 30A Foyer circuit and it looks like there are some outside GFP sockets also on the same circuit. As those sockets are used to power such things as electric lawn mower and various power tools, perhaps that justified the higher breaker rating. I assume the wires are also heavier gage there.

An air conditioner, dryer or range with a combination of 120 & 240 volt loads. I can't remember exactly the last time I saw what you are talking about. Probably sometime in the '60s.

Like I said, be specific. This is a world wide group with people using different electrical systems and having different levels of training.

Well they are *supposed* to work that way afterall, it's just common to have issues, especially in modern homes with so many sources of electrical noise as well as filters in power supplies that can attenuate the signal. The two sides are coupled by the distribution transformer afterall which in many cases is only a few tens of feet from the house.

When I was a teenager my friend and I discovered that my X10 remote would operate some of the lights on and in his neighbor's house. We just clicked the dial through each frequency pressing the all lights on button until something came on. Poor neighbors finally disconnected it.

Ordinary devices, like receptacles, are only allowed on a 20A circuit max. The equipment you plug-in, like your lawn mower, is only intended to be plugged into a 20A circuit max. High probability the wire is 15A (#14), small probability it is 20A (#20), about zero probabilty it is

The 30A breaker is a fire hazard.

Browsing through the internet I discovered something that indicates that I don't even need to worry about cross-phase functionality of HomePlug devices if they are the newer AV 200 Mbps variety. There is this FAQ item on in the following link:

Question:In my house are three separate phases. Can HomePlug AV 200Mbps EthernetAdapter connect one phase to another?Answer:Yes, it can. Phase coupling operates without an installation of a phase coupler whileusing the HomePlug AV 200Mbps Ethernet Adapter. You also can establish yournetwork connections via two or three phasesQuestion:In my house are three separate phases. Can HomePlug AV 200Mbps EthernetAdapter connect one phase to another?Answer:Yes, it can. Phase coupling operates without an installation of a phase coupler whileusing the HomePlug AV 200Mbps Ethernet Adapter. You also can establish yournetwork connections via two or three phasesQuestion: In my house there are three separate phases. Can HomePlug AV 200Mbps Ethernet Adapter connect one phase to another?

Answer: Yes, it can. Phase coupling operates without an installation of a phase coupler while using the HomePlug AV 200Mbps Ethernet Adapter. You also can establish your network connections via two or three phases.

The following white paper explains the reason:

What do you think?

Yes, but X-10 remote controls are radio transmitters, so with the chance of using the same house code by neighbors, it's relatively easy to control their lights. X-10 does not use signal encryption.

An A/C, dryer, or any other 240 volt device/appliance would use a single

So, you've never seen were some scab used a pair of breakers for a repair to keep up the number of jobs per day, or when 'Mr. Fixit' didn't want to buy a two pole breaker when he already had a spare single pole? Both knew that there would be no inspection of their crappy work, and things would work long enough to get paid, or flip a crappy rehab.

What a sheltered life you must lead. Some of the things I find would cause you to blow out your brains. I was called in to help troubleshoot a home with multiple intermittents a few weeks ago. It had multiple intermittent neutrals, and a piece of 12-2 W/G used to tie the old wiring into the newer part. They ran two 120 V 20A circuits and used the

As far as " For the record, 3-wire homeruns to a panel to feed two circuits are very much used still today and are not indicative of 1960s wiring.", I never liked that method and don't remember ever using it. It was considered a cheap trick used by 'fly by night' companies.

I like them and they certainly have been common in the past. For example I can think of a hospital where substantially all the 120V circuits to patient rooms started as 4-wire 3-phase multiwire branch circuits. Other circuits were also mostly multiwire. But the 2008 NEC requires a "simultaneously disconnect" for multiwire branch circuits. That does not have to be a multipole breaker - it can be single breakers with a (listed) handle tie. It would make multiwires in the hospital impractical.

AFCIs have probably eliminated most multiwire branch circuits in houses since you can't have a common neutral unless the AFCI is 2-pole. You may be able to get a 2-pole AFCI, but they probably cost far more.

The presence of that thirty ampere single pole breaker in your panel is a real concern. It is a pretty strong clue that the circuit it serves is not properly protected. If that circuit serves regular lighting and receptacle outlets then that breaker is the wrong ampacity and needs to be changed out to match the gauge of wire used in the circuit.

-- Tom Horne