FYI, The bulb spec is probably associated with a particular light output and is not related to the amount of voltage it can take.
If you look at a comprehensive catalog of incandescent bulb products you will see that the same bulb will be listed several different places at various voltages and outputs. They wind the filaments from finer and heavier wire, coil them once, or coil the coiled wire again, support the whole mess differently, and so on. You can run any over them over a range of input. More current = less life. Droopier filaments of double coiled wire make more light and suffer breakage at the multitude of supports which stress the filament = less life. DC = less life. On Tue, Jan 7, 2014 at 6:54 PM, Cor van de Water <[email protected]> wrote: > Lee, > Indeed, I did not think about that "feature" of Christmas bulbs. > But I do know that they will only fuse shorted if a high voltage is > applied, > not near their regular 2.5V operating voltage, otherwise every time you > plug the bulbs in there would be several that light a little early and > get a bit higher resistance and voltage and those would fuse. > I would need to check, but I expect that it will be several tens of > volts (like 50V or higher) before the insulation of the "fuse wire" will > turn the bulb into a short. > I expect that when that happens, the zeners will get too much current > and blow. Now zeners are also known to fail shorted, so something is > going to give in short order. I will need to test what happens to the > fuse wire if it receives over-current. > These strings have a plug-mounted fuse of 3A, so the wire should at > least be good for 3A ;-) > BTW, I found the spec for the bulb and it is 2.5V 200mA. > > Cor van de Water > Chief Scientist > Proxim Wireless Corporation http://www.proxim.com > Email: [email protected] Private: http://www.cvandewater.info > Skype: cor_van_de_water Tel: +1 408 383 7626 > > > -----Original Message----- > From: [email protected] [mailto:[email protected]] On > Behalf Of Lee Hart > Sent: Tuesday, January 07, 2014 9:23 AM > To: Electric Vehicle Discussion List > Subject: Re: [EVDL] Free bulbs for zener-reg balancer > > Cor van de Water wrote: > > I know that Lee has posted regularly about his zener+bulb balancer > > and today I was finally making the connection while freeing our > > Christmas tree from its light strings... > > > > I have no clue why they strung *12* strings of *50* lights each in a > > 6-ft tree. No wonder it consumed somewhere around 260 Watts. > > Maybe they lived in Minnesota. Excess power usage in the winter isn't > waste -- it heats your home! :-) > > > While unstringing, I was wondering what to do with the removed lights. > > These are 2.5V lights that draw about 22W per string, approx 180mA > > according to my Kill a Watt meter. > > Then it hit me - these are probably perfect to use in balancers. > > That's not a bad idea! :-) Though there is one shortcoming: These bulbs > are designed to fail *shorted*. If one burns out, it shorts so the rest > of the string will still light. That would be bad news if it's across a > battery that can supply unlimited current. > > You'd have to experiment with a burned-out bulb to see just how high the > > current gets, and if it would be a safe failure. > -- > "Obsolete" means nothing more than "the salesmen would prefer you buy > something else." -- Dave McGuire > -- > Lee Hart -- See my Xmas projects at www.sunrise-ev.com/projects.htm > _______________________________________________ > UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub > http://lists.evdl.org/listinfo.cgi/ev-evdl.org > For EV drag racing discussion, please use NEDRA > (http://groups.yahoo.com/group/NEDRA) > > _______________________________________________ > UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub > http://lists.evdl.org/listinfo.cgi/ev-evdl.org > For EV drag racing discussion, please use NEDRA ( > http://groups.yahoo.com/group/NEDRA) > > -- Put this question to yourself: should I use everyone else to attain happiness, or should I help others gain happiness? *Dalai Lama * Tell me what it is you plan to do With your one wild and precious life? Mary Oliver, "The summer day." To invent, you need a good imagination and a pile of junk. Thomas A. Edison<http://www.brainyquote.com/quotes/quotes/t/thomasaed125362.html> A public-opinion poll is no substitute for thought. *Warren Buffet* Michael E. Ross (919) 550-2430 Land (919) 576-0824 <https://www.google.com/voice/b/0?pli=1#phones> Google Phone (919) 631-1451 Cell (919) 513-0418 Desk [email protected] <[email protected]> -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140107/b0f0b785/attachment.htm> _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
