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[Mike Sokol]

This is from a DIY site about troubleshooting home circuit breakers tripping. They linked to my NSZ blog but have not contacted me directly. All I could say would be "Duh"...

Mike

=======================================

We have a 15 amp breaker that keeps tripping. This is something that just started happening. This is what feeds off that breaker: livingroom lights, 2 TVs, kitchen lights, fridge, washer, dryer, master bedroom, guest bathroom, laundryroom lights, all porch lights, and a new gas heater with an electronic ignition and fan. This is a 1977 doublewide mobile home. What could suddenly cause this to happen and is it dangerous?   

[Stephen Swaffer]

If the question, "is it dangerous?" is referring to the 1977 doublewide the answer is yes. Most likely that circuit is wired though the cheapest backstab devices they could find.  If you have that much on one circuit my question is how many of those devices show serious signs of overheating.

At least the kitchen small appliance circuit (s??) is/are separate! 

[Mike Sokol]

If the question, "is it dangerous?" is referring to the 1977 doublewide the answer is yes. Most likely that circuit is wired though the cheapest backstab devices they could find.  If you have that much on one circuit my question is how many of those devices show serious signs of overheating.

At least the kitchen small appliance circuit (s??) is/are separate!

On one of the trades forums where I've been linked to, cable TV installers are advised to test mobile homes for hot-skin voltage before touching them. Apparently some have corroded or missing neutral-ground bonds, so the frame and body of the mobile home becomes energized up to 120 volts. A number of cable installers have been shocked, and IIRC at least a few of them electrocuted (died) while standing on the wet grass and touching the side of the building.

[Keith Broughton]

This is something that just started happening.

Really!?!
And they can't think of anything they might have plugged in recently? (sheesh)

[Steve M Smith]

Is it dangerous?  Not when it has tripped!


Steve.

[Jonathan Johnson]

What could suddenly cause this to happen...?

They answered their own question:

...and a new gas heater with an electronic ignition and fan

Apparently they don't understand circuit loading and what might cause a circuit breaker to trip. We take that understanding for granted, but I guess that's not something they teach in school, so perhaps we shouldn't be so hard on them!

[Keith Broughton]

They answered their own question:

Apparently they don't understand circuit loading and what might cause a circuit breaker to trip. We take that understanding for granted, but I guess that's not something they teach in school, so perhaps we shouldn't be so hard on them!

You make a good point.
Most people don't understand you can't have a toaster, kettle and microwave running at the same time on a 15 A cct.
Thankfully, cct breakers work to save them

[Mike Sokol]

Apparently they don't understand circuit loading and what might cause a circuit breaker to trip. We take that understanding for granted, but I guess that's not something they teach in school, so perhaps we shouldn't be so hard on them!

Amazingly, I've done a lot of education in the RV industry where the idea of voltage drop and heating of overloaded extension cords is poorly understood. For instance, a number of RV lifestyle writers told me that my video on extension cord overheating was news to them. https://www.youtube.com/watch?v=WZznobYGF_c

So yes, most people assume that if you can plug it in and it comes on, it must be safe. Since the plugs of USA wiring are not fused like their UK counterparts, you can easily wire up something that will allow you to dump 30 to 50 amps down a 16 gauge extension cord rated for maybe 13 amperes. Every year in the US we have lots of space heater fires caused by hooking up an 1,800 watt electric heater on a 16 or 18 gauge extension cord. That's a recipe for an electric fire.

[Steve M Smith]

Are there no fuses in your extension cords either?  The most common type here is a fused 13A plug at one end and four 13A sockets at the other end.  There is usually a fuse at the socket end too so even if we were to cut off the plug and put an industrial 16A unfused plug on it, the cable is still protected to 13A.


Steve.

[Keith Broughton]

Are there no fuses in your extension cords either?  The most common type here is a fused 13A plug at one end and four 13A sockets at the other end.  There is usually a fuse at the socket end too so even if we were to cut off the plug and put an industrial 16A unfused plug on it, the cable is still protected to 13A.


Steve.

Nope. No fuses.
It opens up the possibility of grossly overloading extension cables by uninformed users.

[Steve M Smith]

It opens up the possibility of grossly overloading extension cables by uninformed users.

With ours, you can potentially plug an infinite number of appliances into one socket and have it all protected from overload.

So although a setup like this might look a bit scary:



As long as the total load does not exceed 13A (3000w) all will be o.k.  And if it does, a fuse will blow somewhere.


Steve.

[Tim McCulloch]

You make a good point.
Most people don't understand you can't have a toaster, kettle and microwave running at the same time on a 15 A cct.
Thankfully, cct breakers work to save them

I bought a home with the bifecta of things home inspectors don't want to see:  Zinsco and Federal Pacific breaker boxes. FP got sued out of existence because their breakers don't trip at 400% of load over 20 minutes.  The Zinsco ("Magnetrip") breakers will trip (quickly, I might add) but the contacts weld themselves to the bus bars.  I'll take the Zinsco...

Since I live alone and have some semblance of electrical responsibility I avoid overloading circuits, but as Mike's example shows, too many folks just plug stuff in without regard to power consumption.  Electricity has been made so relatively safe that it is treated with disregard by the public.

[Keith Broughton]

With ours, you can potentially plug an infinite number of appliances into one socket and have it all protected from overload.

So although a setup like this might look a bit scary:



As long as the total load does not exceed 13A (3000w) all will be o.k.  And if it does, a fuse will blow somewhere.


Steve.

It does look scary but makes sense.
If the same thing were done here, there is still a breaker at the feed end that would trip if the total load was too great.
The problem here is that someone could load all that on an 18 G  cord!...and run it under a carpet 

[Jonathan Johnson]

With ours, you can potentially plug an infinite number of appliances into one socket and have it all protected from overload.

So although a setup like this might look a bit scary:



As long as the total load does not exceed 13A (3000w) all will be o.k.  And if it does, a fuse will blow somewhere.


Steve.

Most commercial facilities (from offices to factories) in Washington state -- I don't know about other states -- have an annual inspection by the fire marshal or fire department. The inspector will cite a facility for having an outlet strip plugged into an extension cord or another outlet strip. (The outlet strips with overcurrent protection are usually acceptable to the inspector. While most outlet strips have overcurrent protection, not all do. Those splitters that hang off the outlet almost never have overcurrent protection.)

They really don't like extension cords where it's obviously there more-or-less permanently -- they consider anything other than "using it right now for a portable tool" to be permanent.

However, those citations rarely result in a fine. Usually, the problem is corrected at time of inspection. If not, the facility is given a window of time (usually a week to a month) to clean things up, at which time they will receive a followup inspection. If not cleaned up by the followup inspection, then they may receive a fine.

People in the United States don't like inconvenience. If a fuse -- rather than a circuit breaker -- was present in every power plug, someone would probably sue the manufacturer for failing to provide for their convenience. And being able to overload a cord would be considered a convenience. Not to mention that 80% of Americans would be too stupid to figure out how to replace the fuse, so they would just throw the thing out.

Of course, Americans like to sue on the drop of a hat, so if their house burns down because of an overloaded, unfused cord, they'll sue the cord manufacturer anyway. And they'll probably sue the manufacturers of each item plugged into that cord. And the electrician who wired the house. And the power company. And the store that sold them the cord. And the fire marshal for not inspecting their facility in a timely manner. And the site hosting the online forum where they received bad  advice. (But they can't sue joe5479, only because they can't figure out who the real person behind that avatar is.) After all, it's never their own fault. Sigh.

[Steve M Smith]

These used to be popular here too:



This allows four plugs into one socket... and yes, it also has a fuse!


Steve.

[Jonathan Johnson]

These used to be popular here too:



This allows four plugs into one socket... and yes, it also has a fuse!


Steve.

The ONLY plugs in the USA (in common use, anyway) that are fused are holiday light strings. Probably because the wires are about the size of a carbon nanotube, but they are designed so that the user can daisy chain an infinite number of strings together. They are like extensions cords with little tiny lights along their length.

[Stephen Kirby]

The ONLY plugs in the USA (in common use, anyway) that are fused are holiday light strings. Probably because the wires are about the size of a carbon nanotube, but they are designed so that the user can daisy chain an infinite number of strings together. They are like extensions cords with little tiny lights along their length.

Which people attach to their rooflines with staple guns.   

[ProSoundWeb Community]