You may have the wrong idea on that statement. They aren't really a short circuit in the sense of a real short. They only look like one until they get charged up. Many "delays" in a circuit are done using the principle of the effect, of it looking like a short.if capacitors acts as short circuit when first connected,
They do not.if capacitors acts as short circuit when first connected...
What kind of delays do u mean?.can u extrapolate on that?You may have the wrong idea on that statement. They aren't really a short circuit in the sense of a real short. They only look like one until they get charged up. Many "delays" in a circuit are done using the principle of the effect, of it looking like a short.
Will the balancing resistor(equaliser) do any good?They do not.
Of all the possible ways to describe or understand how a capacitor behaves, "acts as a short circuit when first connected" is absolutely the worst because it is the most misleading.
A far better way is to simply understand the basic relationship between voltage, current, capacitance and time in a capacitor: the current through a capacitor (in amperes) is equal to the capacitance (in farads) times the rate of change of voltage (in volts per second) across the capacitor.
In other words, I = C * dV/dt.
And that's it. Everything else follows logically, including what happens if you attempt to suddenly charge a discharged capacitor by connecting it to a powered circuit, what happens if you suddenly discharge a charged capacitor through a very low resistance, what happens if a small amount of current is made to flow through a capacitor, and what happens when the voltage across the capacitor is not changing at all.
I = C * dV/dt. Always.
Whether or not a circuit needs some sort of "protection" from any of these consequences, depends entirely on the details of the circuit and the capacitance and voltages involved.
Have a look on page 8.What kind of delays do u mean?.can u extrapolate on that?
What "balancing resistor"? "Do any good" against what???Will the balancing resistor(equaliser) do any good?
I meant equalizing resistors usually connected across capacitors in seriesWhat "balancing resistor"? "Do any good" against what???
I have absolutely NO idea what you are talking about.
Oh. If that's what you meant, you should have said so. Otherwise, I have no way of knowing what you're referring to.I meant equalizing resistors usually connected across capacitors in series
No. A capacitor does not EVER act as a short circuit when first connected. Anyone who tells you this is misinformed, or a poor teacher.if capacitors acts as short circuit when first connected, how do you avoid that to happen if it may possibly damage the cicuiutry ?
Like in a recent thread of mine, about power on reset.What kind of delays do u mean?.can u extrapolate on that?
Wow..haven't really tried that. I mean capacitors as voltage divider.not very common at all..could you please explain the drawbacks of using caps as VD further..thanks in advance..It is common to make a simple voltage divider out of two resistors in series. Something often forgotten is that you can make a simple voltage divider with two capacitors in series, even at DC. It rarely is done this way because it sucks, particularly with large value capacitors. Large electrolytics have very poor initial value tolerance, and the actual value changes significantly with temperature and with aging. One way to help stabilize the midpoint is to bypass the capacitors with resistors, and one effect of those resistors is that they will discharge the capacitors completely when power is removed.
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There's some instructive insights on websites about restoring old radios - people are often tempted to upgrade the reservoir cap, and the increased charging current doesn't do the rectifier much good.if capacitors acts as short circuit when first connected, how do you avoid that to happen if it may possibly damage the cicuiutry ?
They are used in many, many products, particularly those that have fairly small and constant power requirements. The big disadvantage is that, if they fail they often fail in such a way as to expose the low voltage circuitry directly to the mains voltage. This poses a significant safety hazard, particularly for inexperienced hobbyists who often get lulled into thinking that they can poke around in powered, low-voltage circuits with impunity.Wow..haven't really tried that. I mean capacitors as voltage divider.not very common at all..could you please explain the drawbacks of using caps as VD further..thanks in advance..
In most cases, it takes a while (if you're learning electronics), to begin to see the 'sub-assemblies' of individual components for what they are doing in a circuit. Your statement may change, when you think about filters- signal filters, for example. In almost any kind of band or notch or other kind of 'filter' that filters based on voltage, you're going to have a capacitor and a resistor, or an inductor and a resistor. Indeed, these are voltage dividers. Or a combination of all 3, even perhaps multiple times in combination with each other. All based on whatever you're trying to manipulate.Wow..haven't really tried that. I mean capacitors as voltage divider.not very common at all..could you please explain the drawbacks of using caps as VD further..thanks in advance..
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