The problem is “electrocution” and the solution is “not dying from electrocution”. I personally think that’s worth a little hassle.
In this case, the culprit is either a failing $15 device that is falsely tripping or a $150 device that is putting in excess of 5 mA of current to ground that could cause a person to receive a potentially dangerous shock.
Be sure that it truly is a different circuit. It is not always obvious.
I would try plugging a different device with wattage comparable to the microwave into the outlet and see what happens. Perhaps a hair dryer.
$15 if you can install it yourself. I recently had a quote from an electrician to install one: $260. Spoiler alert: I did it myself
mmm
There are generally two was that electricity kills you.
The first way is that it screws up your heartbeat. This can happen at a surprisingly tiny amount of current, if that current happens to pass through your heart. Most safety standards are built around 5 mA being “safe”, and anything higher is dangerous. The thing is, this is a bit hit and miss. Your heart is more sensitive to disruption at certain parts of its cycle than others, and the amount of current also matters. 100 mA is significantly more likely to throw your heart into fibrillation than 10 mA. Your heart has kind of a funny design in that the fibrillation state is stable, meaning that if no one does anything, the heart just sits there and shakes and is no longer pumping blood. You pass out quickly, and die shortly thereafter.
At higher current levels, you get into the second way that electricity kills you, which is that it literally cooks you to death. This requires a lot higher current levels, but is also a lot less hit and miss. People generally don’t survive a trip to the electric chair.
There are three basic types of protection in a typical modern home.
CIRCUIT BREAKER
This is designed to protect your wiring. It is NOT designed to protect you, at least not directly. An overloaded circuit will catch fire and burn your house down. A circuit breaker is designed to prevent that. A typical circuit breaker trips when the current exceeds 15 amps, since your typical #14 house wiring will heat up excessively at currents above that.
A circuit breaker does ABSOLUTELY NOTHING to prevent electricity from screwing up your heartbeat, and it only prevents you from cooking to death if the current exceeds 15 amps by a significant amount. 5 amps can easily cook you to death, so don’t count on a circuit breaker to save you.
GROUND FAULT CIRCUIT INTERRUPTER (GFCI)
aka GFI, and commonly called an RCD (Residual Current Device) in the UK.
This is designed to protect YOU. Basically, it measures the current going out the one wire with the current coming back on the other wire. If they are different, it assumes that the current found a new path, quite possibly through a human being. Again, most safety standards are built around 5 mA. If the GFCI detects in imbalance of more than 5 mA, it trips. A GFCI protects you from both a low level current that could screw up your heartbeat and kill you, and also protects you from a higher level current that could cook you to death.
ARC FAULT CIRCUIT INTERRUPTER (AFCI)
These were created in response to the fact that a frayed extension cord can easily burn your house down without tripping a regular circuit breaker. The device trips if it detects arcing, like the type of arcing that you get from a frayed cord or a loose wire.
GFCIs are known to be susceptible to nuisance trips, especially when something with a motor or a high current load is plugged into one (i.e. a treadmill). Some brands are more prone to false tripping than others.
AFCIs can also suffer from nuisance trips, especially when an old power tool pretty well mimics an arc fault due to the brushes in the motors arcing as they slide along the contacts on the commutator. Here is a picture for those who don’t know what motor brushes are;
While nuisance trips can be annoying, GFCIs and AFCIs are definitely NOT solutions in search of a problem. Since GFCIs started being required in new construction in the 1970s, the rate of electrocution deaths in homes has dropped significantly (something like 1/10th what it used to be, IIRC).
I am generally all for folks doing things themselves, but electricity is one of those things that can easily kill you if you do it wrong. Make sure you know what you are doing before tackling any electrical job.
I have had two GFCI’s die (and a third that is totally dead, outdoors, need to replace it in the spring). One kitchen one would trip randomly, even when just plugging in the toaster or kettle or hand-held mixer. I have another that only servers the upstairs and downstairs bathrooms, and seems to randomly trpi maybe every month or two - although all that’s plugged in are 2 LED nightlights and a toothbrush charger.
I replaced the kitchen one, the new one hasn’t tripped yet in two years.
Your problem may simply be an older or deteriorating GFCI. It’s a cheap diagnostic and can’t hurt to simply replace it. The other way to be sure is if you have a different GFCI outlet, can you plug the microwave in there and see if it trips? (How dependable is it that it trips?)
Can’t count the number that have died over the years. They age and trigger too fast. I haven’t had any failures with the GFCI breakers in the panel in the addition. Don’t know if they’re less susceptible to problems or just got lucky. Makes sense that an outdoor outlet will have a limited life, someone mentioned kitchen grime as a possible problem, and a GFCI outlet in a bathroom will be exposed to wet and humid air more than others, so maybe the breakers are better protected from those conditions.
I think GFCIs have a lifespan, and are expected to die somewhat regularly. Fortunately, they are fairly cheap to replace.
The big difference here in the UK is that all appliances are either earthed (grounded) or double insulated, so drilling into a live circuit would certainly trip the breaker at the main board, and may melt the drill bit, but the operator would come to no harm.
RCDs are usually reserved for outside outlets that may be connected to tools like lawnmowers and hedge trimmers, where the risk is presumably higher.
No different here in Australia.
Assumes that the operator wasn’t touching any part of the drill bit or chuck. Double insulated, or even battery powered is all well and good, but once you penetrate the mains wiring the protection the drill has isn’t doing anything. On a double insulated drill the chuck is isolated from everything, so once it hits the mains it goes live. Only if you have the fortune to penetrate both live and neutral (or ground) together will the breaker drop. Penetrate just the live and you have a perfectly lethal scenario.
Old school metal bodied drills with an earthed body are safer in this scenario. But they have other issues.
We minimally have a whole of house GFCI, and are moving to combined breaker/GFCI units in anything new.
Sorry. I should have said that under current standards, each circuit would be protected with an RCD at the main box. I test ours a couple of times a year.
Yeah, drilling holes in the wall is just like seat belts in cars, I never really thought about it that way!
LOL
There are many failure modes that can cause electrocution, other than drilling a hole in a conductor. Water intrusion can create a shock hazard, which is why GFCIs are required in wet locations. Cords can become frayed (think vacuum cleaners), or get chewed by pets or vermin. Old tools may be constructed unsafely, etc.
You’re confusing the analogy. The GFCI can save lives and prevent injuries, like seat belts.
The US Independent Alliance of the Electrical Industry says
Since GFCIs have been required, there has been an 81 percent drop in home electrocutions and a 95 percent drop in electrocutions from consumer electrical powered products. The number of fatalities dropped from 1,000 annually to around 100 per year.
Claiming that GFCIs are useless is wildly misinformed.
The springs can wear out over time, but I don’t believe I have had to replace more than a handful across multiple properties. I’m not sure what’s different with yours.