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the current is actually a result of many factors. depending on the voltage type (AC or DC) it could be as simple as resistance in the circuit. when you are talking about AC circuits, there are also capacitive reactance (Xc), inductive reactance Xl), resistance, variances in voltage (fluctuations) , frequency... also the "skin effect" must be taken into account. solid conductors(especially at higher frequencies), are susceptible to eddy currents within the conductor itself. meaning that current just circulates withing the center, forcing EMF (electromotive force) to the outer "skin" of the conductor.
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In the electrical system of the US what is the difference between the neutral and the PE Ground?
US NEC: The neutral conductor is an insulated grounded conductor used as the current return in a circuit. The color designation for neutral is white. The protective ground (PE, protective - earth) is a non-insultated grounding conductor used to shunt fault current to ground, tripping the protective device. The color designation for PE ground is green. Neutral and PE ground are tied together at the distribution panel. PE ground is also connected to a solid earth ground, such as grounding rods driven into the earth. Downstream of the distribution panel, PE ground is never used to carry operational current. Any current flow on PE Ground, other than parasitic current, is considered a ground fault, which must be corrected. In fact, GFCI (Ground Fault Current Interrupting) breakers will trip when neutral current does not match hot current, an indication of PE ground current flow.
Why are AC and DC resistance different?
An AC current tends to flow towards the surface of a conductor due to a phenomenon called the 'skin effect', which acts to reduce the effective cross-sectional area of that conductor.Since resistance is directly-proportional to the cross-sectional area of a conductor, the conductor's resistance to an AC current is, therefore, higher than its resistance to a DC current (which distributes itself across the full cross-sectional area). We call this elevated value of resistance, AC resistance.The skin effect increases with frequency to such an extent that, at radio frequencies, there is little point in using solid conductors and tubes are used instead. At mains' frequencies (50/60 Hz), however, the skin effect is moderate and, so, the value of a conductor's AC resistance is only slightly elevated compared to its true resistance.It's important not to confuse the term 'AC resistance' with 'reactance', which is a function of a conductor's inductance and/or capacitance, and the frequency of the supply.
What is skin effect and methods to reduce skin effect?
with the inductance of a conductor it tends to push current flow to the outsideto reduce the effect you make the conductor hollowwith 80 hz and Cu conductor the current is in the outer 8mm or so.AnswerYou cannot really reduce the skin effect in ordinary conductors; for the sake of economy, you can use tubular conductors. Tubular conductors do not reduce the skin effect, but merely saves copper (if little current flows towards the centre, why have a centre!). However, special, insulated, conductors ('litz' wire) woven or braided in various patterns, can be used for special applications (e.g. high-frequency transformer windings) up to around 1 MHz or so. Because each strand has a very small cross-sectional area, and is insulated from its adjacent conductors, the skin effect is negligible compared with if it were a solid conductor.
How do you calculate diameter of a copper wire conductor and how do we calculate resistance of a copper wire conductor of a particaular length?
You go to the NEC and look at the chart for developed length and the ambient temperature and the load factor and if it solid or stranded wire as stranded allows for more voltage
What is a trausister?
Do you mean transistor? A transistor is a small low-powered solid-state electronic device, consisting of a semi conductor and at least three electrodes: emitter, base and collector. Fiifi Krampah.
