The law

Thread Starter

jaygatsby

Joined Nov 23, 2011
182
I'm still building my power supply. I started thinking: is it really legal to just mess around with mains power? No certifications or proof of competence required?
 

Kermit2

Joined Feb 5, 2010
4,162
Yes

You cannot however legally mess with power lines, transformers, or meters. Once it is past the meter and connections on the side of your house and into the circuit breaker box and various outlets inside your house - stupidity can reign supreme. Hopefully the really stupid ones do it before they breed. :)
 

MrShadyJoe

Joined Oct 23, 2011
2
In the U.S. there may be state or local regulations regarding what you can do as a contractor. But it's not a problem in your own home. Just don't be stupid, even though being stupid IS legal.
 

praondevou

Joined Jul 9, 2011
2,942
I do not mean to offend you but from your other threads, especially the ones where you asked about capacitors I'd say that your main concern should not be if it's legal what you are doing but if it's good for your health.

Since you apparently just started understanding the fundamentals of electronics I would recommend to start with something that isn't related to AC-mains voltage.

You need to be very sure of what you are doing when working with voltages that can supply enough current to kill you in an instant.

As I said, this is meant to be a good advice. :)

I don't know nothing about the lawfulness you asked about... It may be bad if you burnt down your house and the insurance finds out that you inverted in/output of your power supply. But that's another story.;)
 
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SgtWookie

Joined Jul 17, 2007
22,230
Stick with "wall wart" supplies for now. They are quite inexpensive - even free if you scrounge a bit - and are plenty good enough for a large number of hobbyist-type projects.
 

Thread Starter

jaygatsby

Joined Nov 23, 2011
182
I do have a pretty good regulated supply already. But I am making one as an exercise. I am relatively sure that I will make it through this experience with my life and property intact, mostly due to the good advice I continually receive on this forum.
 

spinnaker

Joined Oct 29, 2009
7,830
As Wookie mentioned, you can still make a nice supply with a wall wart. The brick type from an old laptop works great.

The wall wart will save a lot of grief and it will be safer to boot.

This is what I did and it is plenty for my needs. You can make the project more interesting by making it variable and / or selectable set common voltages. Maybe even add a volt meter, current limiting etc.
 

Thread Starter

jaygatsby

Joined Nov 23, 2011
182
Good idea -- I'm well into mine at the moment though. I've rectified the AC and have a very ugly, very non-half-elipse like waveform all above 0V. So far so good! Some capacitors and a regulator and I will be good.
 

crutschow

Joined Mar 14, 2008
34,285
Good idea -- I'm well into mine at the moment though. I've rectified the AC and have a very ugly, very non-half-elipse like waveform all above 0V. So far so good! Some capacitors and a regulator and I will be good.
If that is AC directly from the mains, please send my condolances to any close relatives you may have.:rolleyes:
 

Thread Starter

jaygatsby

Joined Nov 23, 2011
182
After a transformer, but thank you. I do wonder why the waveform is so jagged and crappy looking, instead of parabola-like humps as seen on instructive websites though...
 

thatoneguy

Joined Feb 19, 2009
6,359
I have 2 regulated supplies that are 0-30V one 5A, one 10A, and a 30A 13.8VDC supply. Only the high amperage 12V supply isn't dusty.

I usually use my old phone charger for most projects, since it is 5V@2A, and I don't have to worry about bumping a knob/button and screwing up the voltage.

I've had this "regression" happen on many tools. Have a few scopes and I'll still grab my slightly modified amplified speaker from Radio Shack ($9.99) to trace a signal.
 

thatoneguy

Joined Feb 19, 2009
6,359
As far as the law part.

Why should there be a law against changing things you own in your own house?

The government's job, contrary to it's behavior lately, is not to keep us safe from everything possible. Most of the laws made are to be broken, since a government cannot control an innocent man.
 

Thread Starter

jaygatsby

Joined Nov 23, 2011
182
As far as the law part.

Why should there be a law against changing things you own in your own house?

The government's job, contrary to it's behavior lately, is not to keep us safe from everything possible. Most of the laws made are to be broken, since a government cannot control an innocent man.
What should be and what are, are two different things sometimes. Right or wrong, you need a permit to build a deck in your back yard.
 

Wendy

Joined Mar 24, 2008
23,415
As far as appliences go (which is what a power supply is) I've never heard of regulations of any kind.

However, there are safety standards you should follow for your own protection. This includes using a transformer, a fuse (or some other safety interupt device on the AC side), and a on/off switch. You also should use a chassis ground if you have a metal case.

The life you save may be your own.
 

strantor

Joined Oct 3, 2010
6,782
you can (legally) play around with the mains all you want. you could drill holes through your walls and string romex off breakers through the holes, making a sweet deadly spiderweb replica dangling from your overhead, finally ending at a giant permanently installed tesla coil, mounted inside your ceiling, controlled by what used to be the light switch. You could pull all the existing wiring out of your house and replace it with flat lamp cord. You could do all this legally, but you won't be selling your house when the time comes. Its best to make sure your house stays up to code, so that you can sell it some day. Nobody wants to buy a house that they can't insure, and they need an inspector's signature for the insurance. The inspector won't sign off on any BS. If you plan to die in that house, then by all means, do whatever makes you giggle. I hope its later than sooner (and by natural causes). It's this wish that makes me recommend that you have any electrical work done by a licensed electrician. The code changes every few years, and the licensed guys know the code, and have experience. Now, as far getting a permit for your deck, I can only assume you're talking about a homeowners assosciation. These assosciations are the spawn of satan IMO. They are good in that they keep the value of your home up, by not letting your neighbor erect scrap metal statues 3" from the property line, but overall I hate them. The power they weild is unearned, is too strong, and they flex it too much. They can literally evict you from your own house, even if its paid for, if you don't comply with their demands. Now, the part you have to consider, is that you had to sign the agreement to move in, so its your own fault if they cramp your style. should have moved to the country.
 

Wendy

Joined Mar 24, 2008
23,415
Actually this is not true. There are codes for buildings in cities, you violate those codes at your own risk. If someone dies because you did something to the house wiring you are culpable and prosecutable.

Once you move outside an outlet the wild wild west laws kick in. AAC has standards we enforce on this side of the wall socket, I occasionally have to close a thread to prove it. This is not a threat to this threat, since we are answering questions, but transformerless power supplies regularly get locked down here, along with powering LEDs off of the power mains. Both can be done, but not safely.
 

strantor

Joined Oct 3, 2010
6,782
@bill - AFAIK, you can only be held legally responsible if you do the work for someone else. Like if someone asked me and I said "yeah I'm an electrician, I can hook up your dryer" - and then I wired it to a 40A breaker with speaker wire and the house burned down, then they could sue me and/or I could be charged with manslaughter or criminal negligence or something. If I do the work myself to my own house and it burns down with someone inside, although negligent, it is still an accident. Same as if I negligently set the stove too high and the grease caught on fire and burned the house down with someone inside. That is my understanding, and I am repeating it from what I have been told by several other people. If you know something to the contrary, can you post a link? because I can't seem to find any info on the topic, and I would like to know what the truth is.

My stepfather has a network of about 15 extension cords in his garage attick all plugged into eachother, would he be criminally responsible if it burned down?

EDIT: I'm still googling so far all I have found is that you are responsible if 1.) you are an australian 2.) you rent the property out 3.) you are a licensed electrician
 
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