We run UL tests on various things from rudest prototypes to full production units. UL cares if the construction is the same as will be done in production, or that we document and test any changes from the prototype to the real production unit that are "signifigant" in thier opinion. We have run UL procedures on units where the whole chassis was made in our sheet metal shop, and all of the plastic parts were SLA, and all of the electronics were hand built by me. In an ideal world, we run a pre-UL unofficial test on these rude proto's, then fine tune things and get the factory to make the real UL test units which will fly through UL like a greased armadillo heading for the middle of the road. UL likes production units best of all, of course. --Lawrence "Peter L. Peres" Sent by: pic microcontroller discussion list 08/26/02 12:57 PM Please respond to pic microcontroller discussion list To: PICLIST@MITVMA.MIT.EDU cc: Subject: Re: [EE]: The joys of electronics On Mon, 26 Aug 2002 llile@SALTONUSA.COM wrote: >Well, last week we finished a protptype of a new compact oven, with fancy >LCD controls, a nice microprocessor, and a lot of teeth-grinding work. One >of our UL test technicians was just taking the first prototype into the UL >lab to begin the rigorous UL tests. I had worked a week, one night the >night through, to complete this one handbuilt prototype on time. The >first test involves running the unit for 50 cycles at 20% overvoltage, >which is 144 volts. She calmly misread the meters and hooked this >hard-won prototype to 244 volts. The heating elements got so bright I >could see them across the room, just before the bang. Ever since then, >the tech has been called "240 Volt Marsha" ROFL. Otoh, is there a particularly good reason for running UL tests on a prototype (should not be run on pre-series units - usually the first 10 manufactured using the final factory preocedures and jigs) ? Peter -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics