Burn out 120V lamp on 120V circuit?
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From: Robert Baer on 6 Aug 2010 04:30 Joerg wrote: > Jim Thompson wrote: >> On Thu, 05 Aug 2010 12:02:27 -0700, VWWall <vwall(a)large.invalid> >> wrote: >> >>> Jim Thompson wrote: >>>> On Thu, 05 Aug 2010 11:03:28 -0700, VWWall <vwall(a)large.invalid> >>>> wrote: >>>> >>> <snip> >>>>> The final conclusion, perhaps not shared by all, was that it was >>>>> possible for a passive device to act in this way. One poster even >>>>> showed Spice results with an increase in line current due to motor >>>>> inductance. It was never proved that this increase was enough to cause >>>>> the bulb to fail. >>>>> >>> <snip> >>>>> I have my own theory and can postulate a two terminal passive device >>>>> capable of behaving in this way. (It doesn't even need pre-"charged" >>>>> condensers.) >>>>> >>>>> What say ye all? >>>> Having burned myself seriously as a kid, using an Erector Set motor >>>> winding to blow flashbulbs (†), I can assure you that a bouncing >>>> contact will do it ;-) >>>> >>>> (†) The flashbulb (Press 25) melted over my finger :-( >>>> >>>> ...Jim Thompson >>> Not quite the same thing. I have had #25 flash bulbs go off in my >>> pocket from EMF radiated by trolley lines. An ordinary incandescent >>> bulb requires much more energy to cause its filament to burn out. >> I don't know. Is charge conserved ?:-) >> > > Nowadays charge doesn't need to be conserved anymore, that's so > yesterday. You just print new charge. And if that ain't enough you > borrow some charge. If that still isn't enough you go into closed-door > meetings with some bankers and leverage the leverage, a derivative > scheme that can make 15 charges out of one real charge. Some folks on > the hills are also quite good at that. Plus the bankers will make all > the charge that had gone bad over the years look like new charge and > repackage it for ya, with AAA rating and all the trimmings. Of course, > the one real charge you walked in with will be required as a fee, so the > proper charge bonus can be paid out later. Not to you, of course ... > Translation: Obama really meant "charge" and not "change"..
From: Spehro Pefhany on 6 Aug 2010 09:19 On Thu, 05 Aug 2010 11:03:28 -0700, VWWall <vwall(a)large.invalid> wrote: >A while back, in another Usenet ng, someone asked about using an >ordinary 120V incandescent lamp to slow down a fan motor. A number of >posters replied that they had successfully done this. The usual >discussion of the merits of doing this ensued. > >Then, one frequent poster replied that he had tried this with a small AC >motor, and the 120V bulb, in series with the motor, burned out when the >circuit was completed. > >There was much discussion, with many saying that it was impossible for >any two terminal passive device in series with a 120V incandescent bulb >on a 120V circuit to cause that bulb to burn out. > >Some even set up Spice simulations which were difficult because of the >large variation in the bulb's resistance from cold to fully "on". The >OP was asked to repeat the experiment, which he did several times, with >the same results of the bulb burning out. > >The final conclusion, perhaps not shared by all, was that it was >possible for a passive device to act in this way. One poster even >showed Spice results with an increase in line current due to motor >inductance. It was never proved that this increase was enough to cause >the bulb to fail. > >I haven't tried the experiment myself, since I don't have a suitable >small motor available, and with 120V incandescent bulbs on the >endangered species list, I don't care to sacrifice even one! Some time >ago, I did use a series 120V 100W bulb to slow down the compressor fan >motor in my refrigerator, when the proper replacement was not available. > >I have my own theory and can postulate a two terminal passive device >capable of behaving in this way. (It doesn't even need pre-"charged" >condensers.) > >What say ye all? I say no.
From: Joerg on 6 Aug 2010 10:42 Robert Baer wrote: > Joerg wrote: >> Jim Thompson wrote: >>> On Thu, 05 Aug 2010 12:02:27 -0700, VWWall <vwall(a)large.invalid> >>> wrote: >>> >>>> Jim Thompson wrote: >>>>> On Thu, 05 Aug 2010 11:03:28 -0700, VWWall <vwall(a)large.invalid> >>>>> wrote: >>>>> >>>> <snip> >>>>>> The final conclusion, perhaps not shared by all, was that it was >>>>>> possible for a passive device to act in this way. One poster even >>>>>> showed Spice results with an increase in line current due to motor >>>>>> inductance. It was never proved that this increase was enough to >>>>>> cause the bulb to fail. >>>>>> >>>> <snip> >>>>>> I have my own theory and can postulate a two terminal passive >>>>>> device capable of behaving in this way. (It doesn't even need >>>>>> pre-"charged" condensers.) >>>>>> >>>>>> What say ye all? >>>>> Having burned myself seriously as a kid, using an Erector Set motor >>>>> winding to blow flashbulbs (†), I can assure you that a bouncing >>>>> contact will do it ;-) >>>>> >>>>> (†) The flashbulb (Press 25) melted over my finger :-( >>>>> >>>>> ...Jim Thompson >>>> Not quite the same thing. I have had #25 flash bulbs go off in my >>>> pocket from EMF radiated by trolley lines. An ordinary incandescent >>>> bulb requires much more energy to cause its filament to burn out. >>> I don't know. Is charge conserved ?:-) >>> >> >> Nowadays charge doesn't need to be conserved anymore, that's so >> yesterday. You just print new charge. And if that ain't enough you >> borrow some charge. If that still isn't enough you go into closed-door >> meetings with some bankers and leverage the leverage, a derivative >> scheme that can make 15 charges out of one real charge. Some folks on >> the hills are also quite good at that. Plus the bankers will make all >> the charge that had gone bad over the years look like new charge and >> repackage it for ya, with AAA rating and all the trimmings. Of course, >> the one real charge you walked in with will be required as a fee, so the >> proper charge bonus can be paid out later. Not to you, of course ... >> > Translation: Obama really meant "charge" and not "change".. As in "charge us with more taxes"? It sure seems like that. That process has already been started. As expected :-( -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: Cydrome Leader on 6 Aug 2010 12:43 Greegor <greegor47(a)gmail.com> wrote: > Ok, So you're thinking that the motor is creating > some sort of inductive kick or something a bit like > a slower version of inductive kick caused by the > motor's flyweel effect and switching from a spinning > motor to a spinning generator? > > What kind of voltage do you suppose the > spinning generator effect could add to the circuit? > > Can't a 100W 120 Volt Incandescent light > bulb take a momentary surge of double or > triple the normal voltage? not they way they're made in china these days. try an "rough service" bulb that actually still has has a supported filament and see what happens in the same application.
From: Paul E. Schoen on 6 Aug 2010 18:56
"Joerg" <invalid(a)invalid.invalid> wrote in message news:8c2la2F7vhU2(a)mid.individual.net... > > > As in "charge us with more taxes"? It sure seems like that. That process > has already been started. As expected :-( It was largely Bush's tax cuts (and his wars) that led to the huge deficit. The tax cuts are set to expire soon and if they are allowed to do so it will mean a reversal of the present trend and an additional tax burden mostly on the most wealthy. Not really an additional burden but elimination of a previously established burden that was removed for political reasons. Paul |