Burn out 120V lamp on 120V circuit?
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From: krw on 8 Aug 2010 00:31 On Sat, 07 Aug 2010 20:51:43 -0700, foo(a)bar.com wrote: >On Sat, 07 Aug 2010 22:15:34 -0500, "krw(a)att.bizzzzzzzzzzzz" ><krw(a)att.bizzzzzzzzzzzz> wrote: >>>> >>>> http://www.cbo.gov/ftpdocs/100xx/doc10068/effective_tax_rates_2006.pdf >>> >>>Thank you. Another typical righteous wing lie exposed. Sad that they >>>actually believe what their extremist conservative deities pronounce as >>>gospel. >> >>Which "lie" is that? The one that states that the "rich" already are slaves >>of the state, who pay for everything? That one, loser? >> > >From the same document, table 1: > >Top 10% have 41.6% of all pretax income and they pay 55.4% of all >federal taxes. >Top 1% have 18.8% of all pretax income and pay 28.3% of all federal >taxes. Yes, I get it. Convince the loser and we'll have one fewer Obamanut. I was specifically answering PeterD's assertion that the middle class pays all the taxes. No, it's far worse than that. Close to half are net receivers.
From: Paul E. Schoen on 9 Aug 2010 17:41 <krw(a)att.bizzzzzzzzzzzz> wrote in message news:ajcs56h4aem5la2screarnk1pocf065ps6(a)4ax.com... > On Sat, 07 Aug 2010 20:51:43 -0700, foo(a)bar.com wrote: > >>On Sat, 07 Aug 2010 22:15:34 -0500, "krw(a)att.bizzzzzzzzzzzz" >><krw(a)att.bizzzzzzzzzzzz> wrote: >>>>> >>>>> http://www.cbo.gov/ftpdocs/100xx/doc10068/effective_tax_rates_2006.pdf >>>> >>>>Thank you. Another typical righteous wing lie exposed. Sad that they >>>>actually believe what their extremist conservative deities pronounce as >>>>gospel. >>> >>>Which "lie" is that? The one that states that the "rich" already are >>>slaves >>>of the state, who pay for everything? That one, loser? >>> >> >>From the same document, table 1: >> >>Top 10% have 41.6% of all pretax income and they pay 55.4% of all >>federal taxes. >>Top 1% have 18.8% of all pretax income and pay 28.3% of all federal >>taxes. > > Yes, I get it. Convince the loser and we'll have one fewer Obamanut. > > I was specifically answering PeterD's assertion that the middle class pays > all > the taxes. No, it's far worse than that. Close to half are net > receivers. The money paid by people in taxes to the government either goes back to other taxpayers (wages, purchases, and even social security, Medicare, and welfare), who spend it locally, stimulating the economy, or it goes to those who do not contribute to economic health. The only bad that results from tax and spend is a slight reduction of discretionary income for the upper tax brackets, and a net outpouring of wealth when the money finds its way into the criminal element (such as the huge drug market), and foreign powers and terrorist groups who use the money for destructive purposes. Even so-called wasteful spending still (ideally) recirculates back into the economy and promotes business growth and jobs. Tax and spend means it hurts a bit now. Borrow and spend means it's gonna hurt more later. That was the result of Bush's tax cuts. Restoring the previous structure stabilizes and perhaps reduces the debt. Paul
From: Paul E. Schoen on 9 Aug 2010 18:18 "Sylvia Else" <sylvia(a)not.here.invalid> wrote in message news:8c6oelFig4U1(a)mid.individual.net... > On 6/08/2010 4:03 AM, VWWall 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? >> > > When the circuit's turned on the bulb filament has a lowish resistance, so > a large current can build up in the inductance of the motor. Then the > filament heats up, its resistance increases, and the inductor pushes the > voltage up to keep the initial current flowing, with the result that the > bulb filament has to handle an overcurrent for a period. > > Whether this will destroy the bulb would depend critically on the > characterstics of the filament and the size of the inductor. > > So I'd have thought that the answer was that it's possible, but actual > mileage will vary. That is food for thought (and thanks for replying on topic instead of getting into politics). I don't think a very large current would build up in the motor, especially a small fan motor which is relatively self-limiting even with locked rotor. If the motor stalls, then the maximum current would be initially limited by the bulb cold filamant resistance, and the locked rotor characteristics of the motor. At worst it would be about the same as connecting the bulb to the line through a short, and since this is AC there is not a constant build-up of inductive energy. If the motor runs, then there may be some energy build up from the flywheel action of the load, but this would build very slowly in comparison to the heating of the filamant and eventual stabilization at a lower speed. The motor itself should only be able to generate the same amount of power that is involved in running at full load, which should be less than 1/8 HP or less than the 100W rating of the bulb. So even flywheel action should not be able to account for enough power being pumped into the bulb to blow it out, especially at turn-on. Paul
From: PeterD on 9 Aug 2010 18:39 On Mon, 9 Aug 2010 17:41:21 -0400, "Paul E. Schoen" <paul(a)pstech-inc.com> wrote: > >The money paid by people in taxes to the government either goes back to >other taxpayers (wages, purchases, and even social security, Medicare, and >welfare), No, much goes to non-tax payers. >who spend it locally, For imported goods usually. >stimulating the economy, or it goes to those >who do not contribute to economic health. Which is virtually all of it. > The only bad that results from tax >and spend is a slight Define 'slight'. >reduction of discretionary income for the upper tax >brackets, In this case, 'upper tax' is anyone who pays tax. >and a net outpouring of wealth when the money finds its way into >the criminal element (such as the huge drug market), and foreign powers and >terrorist groups who use the money for destructive purposes. Massive foreign aid must be stopped. As well as our interference with other countries and peoples. > Even so-called >wasteful spending still (ideally) recirculates back into the economy and >promotes business growth and jobs. Tax and spend means it hurts a bit now. It hurts a lot now, and will continue ot hurt. Loss of jobs, loss of homes, inability to go to college, and so forth... >Borrow and spend means it's gonna hurt more later. Borrow and spend is criminal. Anyone in the government who supports that should be hung by their balls until they realize just how wrong it is. >That was the result of >Bush's tax cuts. Still clueless about bush's tax cuts, eh? They brought in more income to the government, and boosted the economey. Obama's massive tax increases, coming very soon, will reduce government income and accelerate the downward slide of the current economey. >Restoring the previous structure stabilizes and perhaps >reduces the debt. > >Paul
From: PeterD on 9 Aug 2010 18:41
On Mon, 9 Aug 2010 18:18:19 -0400, "Paul E. Schoen" <paul(a)pstech-inc.com> wrote: > >"Sylvia Else" <sylvia(a)not.here.invalid> wrote in message >news:8c6oelFig4U1(a)mid.individual.net... >> On 6/08/2010 4:03 AM, VWWall 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? >>> >> >> When the circuit's turned on the bulb filament has a lowish resistance, so >> a large current can build up in the inductance of the motor. Then the >> filament heats up, its resistance increases, and the inductor pushes the >> voltage up to keep the initial current flowing, with the result that the >> bulb filament has to handle an overcurrent for a period. >> >> Whether this will destroy the bulb would depend critically on the >> characterstics of the filament and the size of the inductor. >> >> So I'd have thought that the answer was that it's possible, but actual >> mileage will vary. > >That is food for thought (and thanks for replying on topic instead of >getting into politics). > >I don't think a very large current would build up in the motor, especially a >small fan motor which is relatively self-limiting even with locked rotor. If >the motor stalls, then the maximum current would be initially limited by the >bulb cold filamant resistance, and the locked rotor characteristics of the >motor. At worst it would be about the same as connecting the bulb to the >line through a short, and since this is AC there is not a constant build-up >of inductive energy. If the motor runs, then there may be some energy build >up from the flywheel action of the load, but this would build very slowly in >comparison to the heating of the filamant and eventual stabilization at a >lower speed. The motor itself should only be able to generate the same >amount of power that is involved in running at full load, which should be >less than 1/8 HP or less than the 100W rating of the bulb. So even flywheel >action should not be able to account for enough power being pumped into the >bulb to blow it out, especially at turn-on. > >Paul Damn it, now I'm going to have to run an experiment! <bg> Suggestions to motor specifications? Since we are talking a fan motor, maybe I'll use my shop fan, and a spare 60 watt bulb. |