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resisters/capacitors in AC current?
- Thread starter vslayer
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A simple RC network will not regulate voltage. Capacitors function as resistors in AC circuits. Their capacitive reactance is measured in ohms, and it depends on the frequency of the current and the capacitance of the components. Here is a calculator for determining capacitive reactance (also expressed as X[sub]c[/sub]).
Dips in the line are not very likely to shorten the life of an incandescent lamp, provided that the line voltage does not rise very rapidly back to nominal. Surges are, and can be mitigated using inductors and varistors. Your best bet is probably to use a COTS surge suppressor rather than making something yourself.
Dips in the line are not very likely to shorten the life of an incandescent lamp, provided that the line voltage does not rise very rapidly back to nominal. Surges are, and can be mitigated using inductors and varistors. Your best bet is probably to use a COTS surge suppressor rather than making something yourself.
Fraggle Rocker
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If you're burning out incandescent bulbs your problem is more likely consistently high voltage. We had that problem in a house once and our voltage was between 120 and 125. Most electronics will self-regulate for such a small variance and perhaps slowly wear out their power supply circuits, but simple things like light bulbs and motors will enthusiastically burn themselves out.
I haven't seen any "greenplugs" in a long time, they were once marketed to squelch the current spike you get on an electric motor when it starts from a dead stop, which can burn out the motor while wasting a lot of power. If you can find something like that to put in your circuit, it might help.
I haven't seen any "greenplugs" in a long time, they were once marketed to squelch the current spike you get on an electric motor when it starts from a dead stop, which can burn out the motor while wasting a lot of power. If you can find something like that to put in your circuit, it might help.
the other way would be to convert it to DC powe and then put a cap on the line
4 one way diodes will convert AC to DC quite easerly (as long as they are rated for that much voltage and current.
you lay them out in a dimond patten so that the active and the netural flow one way when positive and it flows the otherway when negitive so that the same line is always holding the same current. Then a cap on the line fixes the drop in power when they are at zero and you have yourself a DC circut
4 one way diodes will convert AC to DC quite easerly (as long as they are rated for that much voltage and current.
you lay them out in a dimond patten so that the active and the netural flow one way when positive and it flows the otherway when negitive so that the same line is always holding the same current. Then a cap on the line fixes the drop in power when they are at zero and you have yourself a DC circut
The problem with that idea is that bridge rectifiers raise an alternating current to its peak voltage. Wall current is 120 volts RMS, but more like 170 volts peak to peak. V[sub]peak[/sub] is what the filter capacitor will be charged to in an unloaded condition, such as when the light switch is off. Turn the switch on, and you'll have one hell of an inrush current across the cold filament, which will be even stronger than the inrush current from a 120V[sub]RMS[/sub] source (and remember that tungsten filaments have a negative temperature/resistance coefficient that causes them to burn out most often upon being turned on). Under load it will drop to something closer to 120V, but that all depends on how loaded the rectifier is and what sort of load is connected to it (inductive, resistive, etc.) and the higher voltage upon turn-on will kill the lamp quickly.
Honestly, a run-of-the-mill COTS (commercial off the shelf) surge suppressor is your best bet.
Honestly, a run-of-the-mill COTS (commercial off the shelf) surge suppressor is your best bet.
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