licensure/circuits

[desnov74]

HELLO ALL;

FOR CIRCUIT DESIGN WHAT ARE SOME APPLICATIONS/SERVICES WHERE ONE NEEDS TO BE LICENSED?

THANKS!

 

[itsmoked]

You need to not use all caps. And you need to define what you are referring to as "Circuit".

If you mean electronics. You need no license. They can actually be a liability.

If you mean public or commercial power circuitry then you need a licensed stamp on them by someone licensed.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[melone]

Do you mean PE / PEng / etc.?

 

[desnov74]

Ops! Sorry for the editorial errors.

To clarify my question, I believe it can be broken into two parts:

A) For custom applications, can a product be designed by an engineer, without UL or third party testing? To be accepted by AHJ these designs would have to meet a performance code code standard? This would usually invovle simulation, testing, and/or analysis. And would they not require a PE signature since they are affecting the public?

B) Since many electronic/electrical ciruits affect public safety, to design custom electrical circuits in some circumstances is a PE required.

(examples ie. sensing alarm circuits, over-voltage and suppression circuits, EMI/RFI suppression, etc.)

PS please excuse my ignorance, just starting out on the "practical side" Thanks again.

 

[itsmoked]

A lot of AHJ would require UL or ETL or FM. This can also be driven by insurance companies insuring corporations. They can often demand this too. Something that has UL doesn't need a PE stamp. That would be more for something engineered. Like the wiring for a public building.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[melone]

itsmoked,

Can you please elaborate on the last two lines of your previous post?

 

[Noway2]

More often than not the AHJ will require a minimal set of standards such as UL approval in addition to their own standards and often times, if it is related to fire protection, Factory Mutual (FM) approved equipment will be requried. Typically the equipment will require at the very least UL aproval, meaning it is a UL evaluated and listed product. To get the UL approval, UL engineers will need to both witness the operation of the equipment, evaluate the equipment for safety, and then periodically audit the manufacturer to ensure that what they approved is being built. FM does the same thing, but focusing on different test criteria. Equipment that falls under the requirement of needing UL approval does NOT need to be approved by a PE to be used in public safety, however the electrical wiring supplying the UL listed equipment may.

The AHJ also has the abilty to overide certain requirements and things that are prohibited by the standards. For exanple, it is illegal per NFPA-20 to have a circuit that will automatically shut down a fire pump in the advent that suction side pressure is lost. However, in several states, such as Indiana and Ohio, it is REQUIRED to have such a shutdown. In these instances, the AHJ is able to override the national standard.

 

[itsmoked]

melone; If you mean these two?

If you mean electronics. You need no license. They can actually be a liability.

It is the standard target shooting by lawyers. If something were to go wrong with a circuit done by a PE they become the focus of any lawsuit because the PE is "held to a higher standard".

If you mean public or commercial power circuitry then you need a licensed stamp on them by someone licensed.

I mean if you are designing the wiring for a public or commercial facility it has to be approved by a PE in most cases. Or if it is some control apparatus it is likely needed to be UL/FM/ETL 'stamped'.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[wvphysicist]

Being new, I don't know what AHJ is or ETL.

Should I conclude that any low power, battery powered, non RF transmitting, non medical, self contained, toy is safe from legal, license, or approval, requirements?

 

[itsmoked]

Nope. You cannot assume that. If the device oscillates above 10kHz you need certification.

AHJ = Authority Having Jurisdiction. (Like a city electrical inspector.)

ETL = Electrical Testing Laboratories. (One of UL's competition.)

Keith Cress
kcress -

http://www.flaminsystems.com

 

[MacGyverS2000]

Oscillating devices must be tested according to FCC rules... UL is electrical safety.

Dan - Owner

http://www.Hi-TecDesigns.com

 

[Warpspeed]

A very great deal depends on where in the World you are located, and the type of equipment, and its application.

Usually the equipment itself needs to comply with some minimum design and minimum performance requirements. You yourself need not be licensed, but the testing authority that tests, and guarantees compliance must be.

Basically, you need to research the rules and standards governing the type of equipment in the places where it will be used.

By "place" I mean not only the Country, but the application, such as a domestic home, commercial office, heavy industry, aboard an aircraft, down a mine, in a hospital, or some other "place" of operation.

The rules and requirements differ greatly.

For example, if your gadget needs to work in a quiet environment, and the rules say it must emit no more than so many dbA of noise when measured in a very specific way, you get a registered acoustic lab to test it for you.

You yourself do not need a "licence" to do acoustic testing. You get someone else to test it for you. The sound lab will then give you a written document, proof that your gadget complies with the relevant standard sound test, whatever that is.

At the end of the whole process you can then sell your gadget and say it complies with the various recognized international standards. If challenged later, you can dig into your filing cabinet and pull out the results of all the tests to prove full compliance.

You yourself need no license, just good planning, organization, and first class documentation.