Weird Home Electricity
Weird Home Electricity
(OP)
I've got a circuit in my home that is incomprehensible (to me at least). From a new 15A breaker (installed a couple of months ago), the wire goes to a plug in the hall bathroom, to a wall plug in the master bathroom, then to a GFCI plug next to my wife's sink, and finally to a plug next to my sink. Four duplex wall outlets. Two of the holes have night lights in them. The electrician verified that those four plugs were all that was on that breaker (no Dr. Evil heat sinks or anything).
Two to three times a year my wife yells at me that her hair dryer doesn't work. Before we replaced the breaker, I would go to the breaker box and turn it from tripped to off, and back to on. Circuit still dead. Wait about an hour and turn the breaker off and back on and all the plugs are live.
I thought there was something in the breaker that was causing the problem and in spite of the electrician telling me that there is no way it was bad, I had him replace it. Today it did it again except the breaker was not tripped. Neither was the GFCI (which I replaced before I had the breaker replaced). I opened the panel and the breaker shows 122V to common when closed and zero when open. I finally gave up and went to do other stuff. About an hour later I cycled the breaker and all the circuits were live.
It acts like it has to cool off for a while before it will start working again. Anyone have any ideas?
Two to three times a year my wife yells at me that her hair dryer doesn't work. Before we replaced the breaker, I would go to the breaker box and turn it from tripped to off, and back to on. Circuit still dead. Wait about an hour and turn the breaker off and back on and all the plugs are live.
I thought there was something in the breaker that was causing the problem and in spite of the electrician telling me that there is no way it was bad, I had him replace it. Today it did it again except the breaker was not tripped. Neither was the GFCI (which I replaced before I had the breaker replaced). I opened the panel and the breaker shows 122V to common when closed and zero when open. I finally gave up and went to do other stuff. About an hour later I cycled the breaker and all the circuits were live.
It acts like it has to cool off for a while before it will start working again. Anyone have any ideas?
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. —Galileo Galilei, Italian Physicist





RE: Weird Home Electricity
1) breaker tripping with no reciplticle loading do to short?
2) heat from short is opening a break in the feed wire?
RE: Weird Home Electricity
Circuit breakers are also thermal devices and need to cool to reset. It should not take that long though. Check the temperature of the breaker when it trips. A poor connection to the bus bar will cause heating. Heat from an adjacent breaker could also be the cause. GFCI problems can be difficult to find. The trip indicators sometimes do not indicate. Use the test and reset buttons to make sure the breaker is working properly.
RE: Weird Home Electricity
If closing the breaker put 122V to neutral on the load side, the breakers is closed and good. Your hour is waiting for the wiring trouble to cool off and reestablish contact. What ever your problem is, there are far worse ways for it to manifest itself than the repeated tripping of a breaker, like the breaker not tripping. Sounds like a nontrivial problem that should be addressed as soon as practicable.
RE: Weird Home Electricity
I happens every 3-4 months with no pattern that I can see. Not sure that a datalogger is really practical, but I'll look into it. Where would you put it?
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. —Galileo Galilei, Italian Physicist
RE: Weird Home Electricity
The history and age of the house, along with any renovations, would be an indicator of likelihood.
RE: Weird Home Electricity
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: Weird Home Electricity
I would pull the breaker and check for heat damage on the bus and/or the bus extension.
I had to do a rebuild job on an old panel once because of heat corrosion. A couple of breakers were tripping at much less than their rated current due to the heat from bad connections to the bus bars.
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Weird Home Electricity
The house is about 20 years old, and there hasn't been any major renovation in 6 years.
Since the wiring goes from the breaker box to a plug in the hall bathroom (about 15 ft) and then to the master bath (another 60 ft), I'm wondering if that receptacle might be the problem (it seems that if the problem was after the hall bath, the plug in the hall bath would still be live). Does that make sense? I think I'll replace it and see if the problem goes away.
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. —Galileo Galilei, Italian Physicist
RE: Weird Home Electricity
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Weird Home Electricity
So, we know that the fault is sometime is a 24 hour period (she has never had the circuit trip while drying her hair, if it starts it lets her finish). Then I open the breaker manually for about an hour and then close it and the circuit is live for a few months. Let's say that the circuit was dead for 22 hours before it was discovered, what does actually opening the breaker for 1 hour or so change?
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. —Galileo Galilei, Italian Physicist
RE: Weird Home Electricity
what if you didn't do anything with the breaker, would it come back on anyway?
RE: Weird Home Electricity
1. The breaker is actually tripped, not in the on position when the problem is first noted.
2. Immediately after resetting the breaker you have 120V +/- from the breaker lug to neutral.
I think I've read both of those. If both are true the problem is entirely in the wiring beyond that breaker lug.
RE: Weird Home Electricity
Is the GFCI wired correctly? Does the problem persist if the GFCI is replaced?
RE: Weird Home Electricity
RE: Weird Home Electricity
Ivymike, one time (with the old breaker), my wife discovered the problem after I left for work. We just left it till I got home. When I got home I found that the breaker was tripped. I reset it and the power was not restored. I opened the breaker and went to do some other things. Came back about 3 hours later and closed the breaker and everything worked fine for several months.
I'm not sure I understand circuits very well, but when I hit the test button on the GFCI (number 3 in the chain), then it is dead and the plug by my sink (number 4) is dead, but Number 1 and 2 are still live. So I'm not sure how physically a fault in the GFCI or bad wiring on the GFCI kills all 4 plugs with the breaker still closed. Based on my experience with the way this GFCI does in fact work (TEST on #3 kills power to #4, but not #1 and #2), it seems like the problem must be in plug #1 or the first 15 ft of wire.
Am I missing something in my tentative understanding of electricity?
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. —Galileo Galilei, Italian Physicist
RE: Weird Home Electricity
If the circuit is "dead" you need to check if anything else in the house that is normally switched on / in use (when the suspect circuit is operative) is in use at the time the circuit is dead, (clear I hope - read it 3 times and now confused- must be old age creeping up) - possibly a problem somewhere with active or neutral continuity.
I had a problem in my own home which after 6 months investigation was finally tracked down to the community street lights switching on in the evening, there was a low voltage feed coming in thru' the neutral - turns out it is of no consequence just a frustrating exercise locating it.
It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)
RE: Weird Home Electricity
RE: Weird Home Electricity
Basically a 3-pronged plug with a row of LED's that light up in a variety of combinations, depending on the status of the wiring to the receptacle.
I found mine very handy after moving into my current house. All kinds of slap-dash wiring in it.
STF
RE: Weird Home Electricity
RE: Weird Home Electricity
When we recently undertook a major home renovation we specified that all wiring was to be copper only, and terminated under screw terminals, added cost notwithstanding.
No issues yet.
CR
"As iron sharpens iron, so one person sharpens another." [Proverbs 27:17, NIV]
RE: Weird Home Electricity
RE: Weird Home Electricity
Is the electrician 100% certain those are the only 4 loads? This needs to be verified 100%. Once the complete circuit is known then I'd start at the breaker panel and work towards the far end checking the circuit for issues. If a problem can't be found in the breaker or outlet boxes then I'd consider hi-pot or megger testing the wiring to try and find a problem in the walls.
RE: Weird Home Electricity
I will check all the neutral lugs in the box. Intuitively, I can't see how this could be the issue, but my intuition is pretty weak in this stuff.
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. —Galileo Galilei, Italian Physicist
RE: Weird Home Electricity
My home inspector had one of those. About half of my wall plugs were wired incorrectly. I bought a tester, and I replaced all of my switches and outlets, and I made sure they were wired correctly.
--
JHG
RE: Weird Home Electricity
The 5 amp trip just sounds strange.
I once had a breaker that tripped now and then on my dryer, and it would only trip the heater, and not the motor. Found out it was a loose connection in the breaker box on the breaker terminal. It was overheating and tripping the thermal element on one side only.
Inspect each outlet (the inside) for arcing, and signs of overheating (discolored plastic, or copper).
Which leads to another question, if the house is old enough it might have aluminum wiring, so if you find that, it should be replaced.
RE: Weird Home Electricity
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. —Galileo Galilei, Italian Physicist
RE: Weird Home Electricity
RE: Weird Home Electricity
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. —Galileo Galilei, Italian Physicist
RE: Weird Home Electricity
Disconnect everything, right down to taking wires off of outlet terminals and breaker. Reconnect everything one piece at a time.
RE: Weird Home Electricity
RE: Weird Home Electricity
eg:
Check:
Panel to plug 1
Plug 1 to panel
Plug 1 to plug 2
Plug 2 to plug 1
etc.
Basically you need a scope and an oscillator. Skogs may be able to suggest the optimum frequency for testing.
If you get quite different readings from each end of what you think is one length of wire, then it may have a hidden branch that must be located.
If there is a reflection from the center of a wire length when testing from either end, it may be an indication of hidden damage.
I am concerned that there may be hidden damage that may develop into a fire hazard. Expensive testing may be cheap compared to a house fire.
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Weird Home Electricity
I sort of wonder if anybody makes them anymore.
RE: Weird Home Electricity
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. —Galileo Galilei, Italian Physicist
RE: Weird Home Electricity
If I am messing with my house wiring, I turn on a plug-in radio. If I can hear the radio, I don't touch the wires.
--
JHG
RE: Weird Home Electricity
I suspect Bill means a ' TDR ' instrument rather than TRD, but it's the first time I've heard of one being deployed in a domestic setting. Interesting idea - we normally apply it to buried cables to localise faults.
If this problem was affecting my house I'd disconnect all faceplates then individually test each section of cable for insulation resistance and loop resistance. The IR check is easy, and the loop just requires a means of shorting the remote end together. Draw out a simple schematic (literally a box for a socket, a single line for a cable) as you go showing the sequence sockets are connected in. Start from the source and work outward until you find the problem. My guess is that you have something mis-wired hiding behind a faceplate, or a bad loop-in / loop-out connection.
RE: Weird Home Electricity
We also use TDR instruments to locate faults in mineral insulated heat trace lines. I suspect that you may have a hidden tap connection somewhere, or a damaged cable somewhere. With the TDR you should see an echo from the end of the cable at a spacing on the scope that is proportional to the length of the cable. Tap connections and many faults should display an echo that will indicate the distance from the the test point to the fault or tap.
Basically an oscillator is used to send a high frequency signal down the cable. Any shorts, opens, taps or the end of the cable will reflect some of the signal. A scope is used to view both the applied signal and the reflected signal.
If you have access to a scope and are able to procure an oscillator, use a 10 foot length of cable and experiment with different scope ranges and frequencies until you find a combination that yields a usable indication from your test cable. You may then use the length of the test cable as a calibration standard for testing.
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Weird Home Electricity
RE: Weird Home Electricity
My idea for using the carbon monoxide monitor would not be to test the circuit before opening and working on it (your radio idea is a great idea for that). My idea would be to plug it in and go about your everyday duties. If the power cycled on/off while you were home, the loud beep would alert you. This would provide a small amount more information on whether it was only cycling off while the hair dryer was in use, or whether it was cycling on/off at other times when the outlet was not in use. A radio could possibly provide the same information, however, might be a bit disruptive having a radio on 24/7. The CO monitor I have is silent until the power goes off (also beeps when power comes back on - one loud beep for power interruption and that's it) It is loud enough to A) wake you up, B) hear it in the basement, C) hear it over the TV, etc.... My thoughts are that before ripping everything out and redoing the wiring, it might be a good idea to collect a bit more data on what causes it to cycle off.
Lots of other good ideas above. Good luck with diagnosing.
RE: Weird Home Electricity
RE: Weird Home Electricity
The radio is turned on when I am sticking screw drivers and my fingers into light switches and other electrical devices. I need to know when the power is on.
It is turned on at other times too, but then, it is not a safety device.
--
JHG
RE: Weird Home Electricity
They make it much harder to short something live to ground and/or yourself.
lots of good ideas here - someday I need to hunt down some funkiness in my own house's wiring.
Cheers
Jay
Jay Maechtlen
http://www.laserpubs.com/techcomm
RE: Weird Home Electricity
RE: Weird Home Electricity
http://www.youtube.com/watch?v=ZUw79RJMj-g
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Weird Home Electricity
Mike Halloran
Pembroke Pines, FL, USA
RE: Weird Home Electricity
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. —Galileo Galilei, Italian Physicist
RE: Weird Home Electricity
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Weird Home Electricity
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. —Galileo Galilei, Italian Physicist
RE: Weird Home Electricity
Are all the receptacles GFCI? If the answer is yes, none of the wires hot or neutral should be on the load side of the GFCI. If the first receptacle in the line is a GFCI and the rest are not, the first GFCI should have the wires from the panel connected to the line side and the wires feeding the other non GFCI recepts should be on the load side. I have seen electricians do dumb stuff with multiple GFCI's in one circuit. If you could verify the hook up for me I'm sure I can solve your trouble.
Paul
RE: Weird Home Electricity
It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)
RE: Weird Home Electricity
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. ùGalileo Galilei, Italian Physicist
RE: Weird Home Electricity
Dan - Owner
http://www.Hi-TecDesigns.com
RE: Weird Home Electricity
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
RE: Weird Home Electricity
Both breakers are duplex 15A. I don't know if there are any problems with the duplex breakers or not. None of the four loads are very big.
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
RE: Weird Home Electricity
It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)
RE: Weird Home Electricity
If the original
breakersreceptacles are about the same age, this may be age related failures.Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Weird Home Electricity
I live in the high desert and our humidity is usually around 7% RH (hence the swamp cooler instead of AC). The panel is outside. The late afternoon sun shines on it in the winter, but by now it is pretty well shaded.
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
RE: Weird Home Electricity
RE: Weird Home Electricity
Also feel the breakers. When a breaker is hot enough to affect adjacent breakers, the surface will probably be hot to the touch.
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Weird Home Electricity
I started by opening each wall switch and receptacle wiring box (there were both device types in this branch circuit), checking voltages and mechanical integrity of the device and wire nut connections.
When I got to a switch and outlet triple box in the bathroom , I found a neutral wire nut connection behaving as I would not have thought possible with copper wire.. Although the wire nut was mechanically tight, all neutral wires twisted properly seated in the wire nut, one of the wires coming out of the wire nut was intermittently open. By moving the wiring a very small amount with power applied, I saw the connection go open and closed with the movement of the wire.
It turned out that water from a plugged up condensate drain in an air conditioning air handler located directly overhead the wall in the attic had leaked water down inside the wall through the holes for the electrical wiring and repeatedly wetting one of the wire nut connections, causing contaminate or corrosion buildup in the wire nut connection, causing it to go intermittent. In the attic I found the wiring that went down into the wall and saw clear signs of past water leakage from the air handler down into the wiring holes bored into the wall stud plate.
The copper wire had a white coating on it which obviously was dielectric. There was sufficient wire length to cut back to expose fresh clean copper and a new wire nut fixed the problem.
Oddly enough and fortunate for the homeowner there was no black oxide coating on the copper wire from acidic corrosion, that is known to happen when the PVC insulation in NM type wiring gets wet. PVC insulating material when repeatedly exposed to water degrades producing acidic byproducts which will corrode copper.
RE: Weird Home Electricity
Are you anywhere close to New Mexico? I haven't fund anyone here that is willing to go beyond "let's replace something and see what happens"
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
RE: Weird Home Electricity
I certainly would or have an electrican take apart every wire nut connection in the branch circuit and verify their condition. Wires inside a wire nut have also been known to break and still mechanically stay inside the wire nut..
Copper work hardens with mechanical bending and can become brittle enough to break.
RE: Weird Home Electricity
The problem is still that the power gets lost at all the receptacles with the breaker on, right? If yes, there has to be a problem with the wiring between the breaker and the first receptacle.
RE: Weird Home Electricity
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Weird Home Electricity
Just a thought that maybe there is an issue with the neutral on the shared section of the of the two circuits.
RE: Weird Home Electricity
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
RE: Weird Home Electricity
The half size or tandem breakers allowed a manufacturer to increase the rating of some lines of panel boards.
At one time, a major manufacturer used the same bus bars or strips in all panels up to 200 Amp rated panels.
However under the Canadian Electrical Code, not only the rating of the bus bars but also the number of breaker spaces are used to determine the maximum rating of a single dwelling panel board.
Excerpt:
8-108 Number of branch circuit positions
(1) For a single dwelling, the panelboard shall provide space for at least the equivalent of the following number
of 120 V branch circuit overcurrent devices, including space for two 35 A double-pole overcurrent devices:
(a) 16 — of which at least half shall be double-pole, where the required ampacity of the service or feeder
conductors does not exceed 60 A;
(b) 24 — of which at least half shall be double-pole
(i) where the required ampacity of the service or feeder conductors exceeds 60 A but does not
exceed 100 A; or
(ii) where the required ampacity of the service or feeder conductors exceeds 100 A but does not
exceed 125 A and provision is made for a central electric furnace;
(c) 30 — of which at least half shall be double-pole
Most panels could be uprated one at least one size after the introduction of the half size double breakers and the tandem breakers.
Some brands also offer half size single breakers.
(i) where the required ampacity of the service or feeder conductors exceeds 100 A but does not
exceed 125 A; or
(ii) where the required ampacity of the service or feeder conductors exceeds 125 A but does not
exceed 200 A and provision is made for a central electric furnace; and
(d) 40 — of which at least half shall be double-pole, where the required ampacity of the service or feeder
conductors exceeds 125 A and the dwelling is not heated by a central electric furnace.
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Weird Home Electricity
Dan - Owner
http://www.Hi-TecDesigns.com
RE: Weird Home Electricity
I have outlets in the back of the house sharing breakers with lights in the front part, and upstairs... It's a nightmare to chase electrical gremlins, or add lights or outlets.
BTW, there are a ton of good ideas. I'll be dishing out some stars on this thread.
David
Connect with me on LinkedIn. http://lnkd.in/fY7-QK
Quote: "If it ain't broke, I must not've fixed it good enough"
RE: Weird Home Electricity
speaking from 50+ years experience, with plenty of time packing tools, industrial motor and controls, as well as roping houses, couple of things are not sounding right. Just read through all this. I'm coming into this way late, and likely all this has been looked at. However:
Couple of questions:
That first receptacle in the hall bathroom - is it a gfci? Should be.
Is the second receptacle in the master bath a gfci? Doesn't have to be, but could be.
The hair dryer is plugged into wife's sink receptacle, the third receptacle in the string?
I would expect all the bathroom receptacles to be gfci protected. Since the branch ckt CB is not gfci, then my expectation would be:
The first receptacle (hall bath) to be gfci and be wired to protect all down stream. All downstream receptacles will be ordinary non-gfci. OR;
The first receptacle to be gfci, downstream receptacles gfci, wired to first receptacle line side. Until you get to the two receptacles by wife's sink and your sink. It sounds like the two sinks are side by side and are wired with your receptacle fed from wife's sink gfci.
If any of this is true, inspect/replace the first gfci receptacle in the hall bathroom.
If not, color me all wet and move on.
Hope this helps.
The worm
Harmless flakes working together can unleash an avalanche of destruction
RE: Weird Home Electricity
Keith Cress
kcress - http://www.flaminsystems.com
RE: Weird Home Electricity
The receptacles in series are:
- Hall bathroorm--not GFCI, been replaced since July. I know this one should be GFCI and I'm thinking that I'm going to make that change regardless of anything else
- Wall outlet in master bathrrom--Not GFCI, replaced since July
- Wife's plug--GFCI, replaced last year
- My plug--Not GFCI, original.
If this problem stays gone until I turn the swamp cooler back on in the Spring, then I'm going to run a new wire (from my secondary panel) to the hall bathroom and try my best to forget this whole episode.David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
RE: Weird Home Electricity
We'll all wait for the final ruling.
Keith Cress
kcress - http://www.flaminsystems.com
RE: Weird Home Electricity
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
RE: Weird Home Electricity
Happy new years?
Keith Cress
kcress - http://www.flaminsystems.com
RE: Weird Home Electricity
Switch some breakers around and see if the problem stays or if it follows the breaker.
Re; the neutrals. If there are any shared neutrals, there may be field connections in junction boxes.
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Weird Home Electricity
Mike Halloran
Pembroke Pines, FL, USA
RE: Weird Home Electricity
Keith Cress
kcress - http://www.flaminsystems.com
RE: Weird Home Electricity
It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)
RE: Weird Home Electricity
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
RE: Weird Home Electricity
Possibility of water leaking out of the swamp cooler while in operation... and said water getting down into affected electrical circuit somewhere?
Would be similar to fault I mentioned above with corroded neutral caused by water leak out of plugged A/C drip pan.
RE: Weird Home Electricity
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist