Any Laws restricting sale of Mains DIY gear?

Discussion in 'Electronics Resources' started by davo161, Jul 10, 2010.

  1. davo161

    Thread Starter New Member

    Jun 14, 2010
    Just wondering if there are any restrictions in place for selling home made gear, specifically 'Outboard' Audio equipment like; 19" rack Pre-amp/DI's/EQ's/Compressors, running off Mains power?

    I'm in Australia, and I know there are many different regulatory standards around the world like the CE marks and stuff, but am having trouble actually finding any information on what the standards are, how much it might cost to get a piece of equipment cleared, and if I even need to?

    Any help would be much appreciated, as sale of custom goods might be an option for me in the future, but I want to know what I'm aiming/got myself in for, standards wise?

  2. beenthere

    Retired Moderator

    Apr 20, 2004
  3. Wendy


    Mar 24, 2008
    I may have misunderstood the OP, but I think he was referring to any equipment with a power plug for house mains.

    As beenthere mentioned, there are some questions on how you do something inside the box. Many of our newer users (the older ones know better) try to save money by not using a transformer. A capacitor or resistor will not work, only a transformer (not a variac) offers safe isolation.
  4. tom66

    Senior Member

    May 9, 2009
    In the UK, if you do not include safety marks on the product, it's the consumer's risk, as far as I understand. The marks are only to advise they are certainly not required. I guess if an appliance caused significant safety issues it might be pulled. There are still requirements like proper earthing and fuses and such...

    In a product I was designing to run from the mains (just as an experiment, not to put into production), the device used a transformerless power supply (it used a capacitive supply). Thusly, it had to have a proper fuse, discharge resistor and input current resistor. And it had to be properly earthed and in a proper case. That still worked out cheaper than using a transformer as it was only powering a microcontroller + TRIAC, and it still had ~1W standby consumption.

    You should probably get certification anyway, even if it costs a bit of money, because it will probably increase the value of your products...
  5. davo161

    Thread Starter New Member

    Jun 14, 2010
    Thanks for the ideas guys (and girls?), it's very helpful.

    As for using transformers - I wouldn't ever consider using anything else - it just seems easier, safer, and i found some excellent ones that are easily accessible.
    I understand the issues with earthing, and wouldn't use any mains power without a fuse - I've gone under the hood in certain outboard gear and haven't found a one - made me a little uneasy, actually!

    I'm a airline pilot by profession, so i know there are LOTS of things that can kill you, and if you don't 'fear' them and take action (put something in place to stop it killing you), then it will..

    As for the 'CE' markings, I think i have an idea of where i can get more info here is Aus, but was wondering if anyone else had made anything for constant sale that HAD to meet any of these Regs?

    Thanks again guys!
  6. Potato Pudding

    Well-Known Member

    Jun 11, 2010
    Custom built gear as a cottage business?

    Make certain that you talk to an insurer.
    Be choosy about who you sell to and make certain that you have their contact info. Try and make a point of staying in contact. Survey buyers for anything you would want to know about the gear you have sold and detailing any problems that turn up.

    Most of the problems that turn up will be things that need to be detailed as user manual instructions. People tend to use things in ways you wouldn't expect.

    Document things exhaustively, and that should include pictures starting from the build stage that clearly show a chassis number that you create and mark on each unit.

    You might not need things like brand names or lot numbers for components but it wouldn't hurt. Finding out that one brand of capacitor turned out to cause problems would help you more if you knew which chassis had them in.
  7. someonesdad

    Senior Member

    Jul 7, 2009
    I won't presume to advise you on the legalities in different countries; you may want to hire some legal advice for this.

    A marketing barrier can be that distributors won't buy from you (or importers won't import) unless the product has certain safety marks.

    Make sure your design is safe and well-engineered. If you're not an engineer, pay a good one to do a design review. Regardless of any certifications on the product, if a design fault winds up hurting or killing someone, you could be in deep kimchee -- and the legal costs will make all the sphincters on your body slam shut.
  8. davo161

    Thread Starter New Member

    Jun 14, 2010
    wow, that's a good way of putting it! I like my body functions the way they are...

    I'll still look into it a bit more before making and decisions obviously! Thanks for all the help guys, much appreciated.
  9. schmitt trigger

    Active Member

    Jul 12, 2010
    The best option, and one that is even used by many large OEMs, is to purchase an external "brick" power supply, which already has all the required safety agency certifications. The output of the power supply is low voltage DC, and you don't have to deal with the certification burden and expense.

    Additionally, most of those supplies are "universal" input, which is a plus if you plan selling your stuff on places like ebay.
  10. davo161

    Thread Starter New Member

    Jun 14, 2010
    Hey Schmitt,
    Yeah that was probably the way I was going to head in the end, after a few hours of pondering..!

    I've built a 1U rack section that has split my 240V house Mains into 6 IEC plugs. This supplies (so far) 3 of my outboard rack units (only 1 of which is my own creation), with ease. But yes, I've put MANY hours into ensuring its not going to kill me and keep up the supply, safely! But as for mass production, BEHRINGER Audio make one that would be cheaper to buy than I could ever contend with...

    Using a universal and quite simple DC wall wart was my final decision. So now its just a matter of adjusting some components to match a generic supply, changing some plug ends, and testing! Fun fun... Should end up a cheaper unit to produce too...

    I'll let you know how I go!
  11. Harrington

    New Member

    Dec 19, 2009
    Reading up on the IEEE standards should cover everything you need to know about mains appliances There are some laws in the UK regarding mains appliances but as tom66 says Its up to the consumer to observe this which is a bit well cant really say anything can we typical UK this

    They do insist on using a earth insulation test or should do on equipment they used to They don't seem to bother anymore or its not a mandatory requirement
  12. Harrington

    New Member

    Dec 19, 2009
    They are quite funny about transformers though especially the difference between 220VAC European standard and 240VAC UK standard I remember Telefunken UK having an awful lot of trouble with Ferguson Uk with one of their appliances even though it was within tolerance and had been insulation tested

    They weren't very happy with this at all Depends on how funny they want to be They can be really strange about this if they want too I think a lot of this though was done though to prevent Telefunken UK from marketing a perfectly good working appliance

    Normal this !! So rule is less arguments they can present the better off you are Yes It gets as dirty as this sometimes