Home Electrical Wiring Tips:
Did You Know?

Circuit Breakers & Tripping

A circuit breaker can appear to be on, but really be tripped.

A breaker trips much more often for a real short than from some defect in itself.

GFIs and breakers are not usually the bad guy - they trip for a reason. And if your problem would make sense from their tripping but they DIDN'T, something other than them is probably at fault.

In some cases a circuit breaker will trip off only after the circuit has been running things for several minutes. This may not be from an overload but from a poor connection point at, or in, the breaker itself, which develops heat that fools the breaker.


A normal receptacle is sometimes ground-fault protected from elsewhere.

A GFCI receptacle will not trip for an overload.

A GFCI rarely trips from a defect in it. Usually a GFI trips from being miswired or from a fault in something that is plugged into it or into a regular outlet protected by it.

GFI outlets nowadays won't allow you to reset them if the power to them is off.

It is commonly said that GFCI outlets are required near water. Actually the Code says nothing about water -- it just tells what areas of a home must have GFCI protection. And it is only the protection, not a GFCI-type receptacle, that must exist there. Most often, one GFCI receptacle will be providing this protection to a number of standard receptacles (in required locations) fed from it. See GFIs.

Why is a GFCI tripping holiday lights off? Be sure the lights and their cords are not held in wet places, like beauty bark or the ground (anywhere they can't shed water). Also, water can get to a cord's prongs wherever one cord plugs into another.


Most of a circuit can stop working even when the breaker is on and is fine.

The first thought most of us have when there is a circuit outage, is that a circuit breaker tripped off. Very few are aware of how part of a circuit can go dead from a poor connection. And sometimes this kind of outage can be temporary. Finding the bad spot is trickier than resetting a breaker.

A common difficulty for which people contact me is an outage on one circuit that is not due to a tripped breaker or GFI. This is from a poor connection (an "open") along the circuit. Most people don't realize that there is a 50% chance that the bad spot is located at the last still-working item along the circuit. The other 50% of the time, it will be at the first non-working item. Knowing what the circuit consists of is another matter.

If you lose power to much of a circuit, the first of the dead things may have the poor connection, but it is equally likely that the last of the working things has a wire poorly connected from it.

An open neutral is a loose white wire along a circuit. This can be spooky in several ways. 1.) You can get shocked at a light or outlet that is not working; 2.) You can get confused when your tester finds live white wires; 3.) You don't know where the problem is being caused; 4.) Only in the case of an open on a shared neutral (rarer), you may see damage to appliances and/or odd effects in the behavior of your lights.

Light Bulbs

Compact fluorescent bulbs (spiral looking) may last longer, but they die a slow death, running rather dim during their last years. Incandescent bulbs at least let you know when to replace them.

Congress says that by 2014 normal 40-100 watt incandescent light bulbs must no longer be made (to encourage more efficient bulbs, like fluorescent). Remember when your dimmer switches were promoted as saving energy? Guess what? Those dimmers are not able to get along with most fluorescent bulbs! You may be going back to regular on-off switches.

Why do your dimmer switches burn out? Light bulb quality seems to be declining, and I am thinking that this has increased the frequency with which a light bulb will set up a shorting arc when IT burns out. Any short going through a dimmer has a fair chance of killing it. Consider replacing that burned out dimmer with a normal switch.

Now that compact fluorescent bulbs are so popular (mandatorially), people who also have "lighted" switches are finding those bulbs flashing every so often in the dark. For these switches to light up when they are turned off, a little current has to run through the bulb. It was never enough to make incandescents glow, but these new bulbs' starting mechanism stores the current and then releases it.

The design of some screw-in fluorescent bulbs doesn't let them quite "bottom out" in all possible sockets. Don't automatically think the fixture has a problem. You may have to buy a different brand of bulb.


When part of a circuit goes dead due to an open neutral, people testing their wires are surprised to find white wires registering hot (live). An outlet tester calls the condition "hot and ground reversed", but what is really happening is this. Somewhere among the non-working items, a turned-on one lets hotness through its resistance but since it no longer has a path or connection back to the panel (the usual neutral), those whites still show hotness (ready to shock you in fact!).

Sometimes a tester will indicate good power, but still nothing works. This means that a wire connection is POOR rather than bad. Only a little bit of current can get through that point.

Your tester may fool you into thinking a wire is live when it isn't. Here's how. If a wire is dead but is part of a cable containing a hot wire, when you test from this dead wire to ground, you may get a reading, from a few volts even up to 120 volts. An example is one of the traveler wires of a 3-way switch system when that traveler is not the one being energized. This phenomenon is called Phantom voltage.


Replacing a switch or receptacle can open a can of worms.

Can't plug cords into an outlet easily? The receptacle may be one of the new type called Tamper Resistant. Like childproof caps, these can give adults difficulty too.

Upgrading an electrical panel to greater space or current-capacity does nothing (by itself) to alleviate the overloading of a particular circuit.

Where the 2011 NEC code is in effect, 2014 will mark the year that anyone (including homeowners) replacing a receptacle in most rooms of a house will be required to make it be arc-fault protected. Most often this will have to be accomplished by installing a costly device there or earlier in the circuit. No more "if it's broken, just fix it."

Energy Saving

Incandescent lights become much more energy efficient in the cool seasons by reducing your use of your heating system. I'm serious.

This little energy tip came to me in the tub. In the middle of a long bath you add some straight hot water to warm it back up. Before you do, drain the tub down an inch or so. That way you use less new hot water to achieve your desired temperature.

General Electrical

The voltage in half of all U.S. homes is greater than most light bulbs are designed to run on.

The resistance of an incandescent light bulb filament is very much less when measured with power off than it is when carrying its current.

Home electricity doesn't flow in one constant direction.

When on their high setting, hair dryers sold today use the entire capacity of a 15-amp circuit.

A turned-on dimmer switch normally produces some heat.

If someone tells you your problem is "probably a bad ground," tell them to go back and work on their car's electrical system. In houses, the only trouble a bad ground would commonly give you is a shock, and even that would be rare.

The word "receptacle" sounds like something receiving. But the word "outlet" sounds like something giving. How can they both refer to the same thing? An outlet is giving electricity out, from the perspective of the electrical system. But from the perspective of you, the user, a receptacle is receiving your what you plug in, in order to run a lamp or such.

Should you be afraid of overloading your circuits? Generally not, because you have circuit breakers! They stop overloads in their tracks by tripping the circuit off before a load gets "over". Still, you might say, we can't tell when some trusted electrical component might be faulty and overheat. True, but that is an unexpected "undercapacity", not an overloading on your part. The main exception to this is the overloading of light fixtures or extension cords, not whole circuits. These state the maximum wattages they are to serve and do not usually have built-in trip-offs. So pay attention with those. But don't worry about using your circuits. Life is too short.


The bulk of home electrical wiring problems can be divided into four classes: Outright mistakes in installation or connection. Inferior connectings. Inferior materials. Damage (including wear).

Quick multi-tip: To reset a breaker push off harder first. A GFI won't trip for an overload. Assume a breaker or GFCI is tripping for a reason. Shorts can kill dimmers. Bright or dim lights might be the power company's fault.

Three assumptions that can be wrong: The breaker is responsible for things on a circuit being dead. The loose connection along a circuit will be found at one of the circuit's dead items. You can't get shocked at an outlet that doesn't work.

Certainly, many home electrical wiring problems come from homeowners DIYing, but when the populace is kept ignorant and kept away from practical knowledge of their own property, this can be expected. If doing it yourself were encouraged more, I think the level of your competence would increase.

There are three things people imagine, only one of which I have come across: A breaker that trips on its own from mechanical weakness. Signs that a rodent has chewed on housewire for fun or for the taste of it. [I did hear that rodents which have been poisoned will chew on things randomly; do any of you know if this is true?]. A person who can testify that they were being shocked and then a GFI tripped and saved them -- this is the one I have finally heard of. Such a survivor, Walt S., told me in Jan. 2009 that a while back he was being shocked and the GFI stopped it.

What are people's three worst fears about their home wiring? First, that something will go wrong with the wires back in the wall, where it's hard to know about or do something about. Second, that it will have been caused by a malicious chewing varmint. And third, that this is sure to start a fire. Each of these scenarios by itself is rare. Imagine how rare they are together. Most problems live safely and conveniently within the electrical boxes that are required.


Is electrical troubleshooting for a home simple? Sometimes Yes. Sometimes No. If you read this site thoroughly, you will realize that more is involved than other sites suggest. And you may wonder if it is more than you want to deal with. But if your careful reading brings you increased understanding, then you are more equipped to deal with the possibilities.

The more that new safety devices are required, the more home electrical wiring problems there will be because of this.

Perhaps the most common search bringing people here amounts to: why won't my usual resetting procedures restore power. That expresses a lot of different situations, so I can't give a single answer. But if you are willing to learn a little more here about how your system of circuits works, I think you'll have a better chance of handling your problem.

What Is Troubleshooting? Troubleshooting is not improving or upgrading things that work. Troubleshooting is not even looking for possible trouble -- that's prevention. The common notion is exact and right: troubleshooting is shooting in the direction of a real glitch till you have flushed it out where you can shoot it dead.

"Thank you so much for your high-quality, authoritative site. As you know, those are very hard to come by these days. Your site gave me the courage to do household electrical repairs again and taught me more than I knew before." -Steve

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