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A vector impedance meter is used to measure impedance and phase angle, this is done by calculating voltage and current through an impedance and then calculating Z and phase angle with that, now there are two modes for operation i.e constant current mode and constant voltage mode.
CONSTANT CURRENT MODE
construction = first of all there is a wien bridge oscillator(w) to choose frequency then an AGC amplifier(a) to regulate current then a z switch control(zs) which regulates gain of AGC amplifer,
feedback to AGC amplifier is done by an dc differential amplifier(dc)
dc
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w--------->a--------->z
now there is an ac differential amplifier too(ac) which gets one input from the z switch and one from the unknown impedance(imp), and there is a transconductance amplifier too which gets one of his input from the unknown impedance
dc<-------------------------------------------
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w--------->a--------->z----------->ac-------------|------------> z meter
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_____| | |
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imp | |
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|________|___>rt___>|
working---> in constant current mode we have to maintain constant current through impedance so current is made to come to unknown impedance from z switch, then that current goes through trans-resistance amplifier, which converts that current to a voltage that is sent to a dc differential amplifier and is compared with a reference voltage in dc differential amplifier then the difference between voltages is amplified and sent to AGC amplifier, so AGC together with z switch this way maintains constant current through unknown impedance,
now for calculation z-magnitude,
ac differential amplifier gets input from unknown impedance and z switch, so difference is amplified and sent to a band pass filter which filters out then the filtered signal is sent to a z-magnitude meter which is calibrated to read z directly.
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What is the impedence?
Impedance is the complex form of resistance. Impedance takes into account capacitance and inductance in a circuit as well. Impedance can be represented as resistance as a function of frequency.See link.AnswerImpedance is not a 'complex form of resistance'. It is the vector sum of a circuit's resistance and reactance. In electrical engineering, 'resistance' has a very specific meaning, and cannot be used to denote 'opposition'.
Does the impedance of an RL series circuit varies inversely with the frequency?
The simple answer is no. The impedance of an R-Lcircuit is the vector sum of the circuit's resistance and its inductive reactance. Resistance is determined by the length, cross-sectional area, and resistivity of the conductor (although its 'a.c. resistance' is proportional to the frequency squared), whereas the inductive reactance is directly proportional to the frequency of the supply.
An inductor has an inductive reactance of 64ohm's and a wire resistance of 36ohm's what is the impedance of the inductor?
Impedance is a vector sum using the formula Z = square root (XL2 + R2); where Z = impedance, XL = inductive reactance, and R = resistance. Therefor the formula for a circuit where XL = 64ohm's and R = 36ohm's is Z = square root(642 + 322); Z = 71.6ohms.
What is meant by the term capacitive resistance?
That term to me is incorrect it should be capacitance impedance. Resistance is linear impedance. CAPACITANCE will follow a vector caused by the capacitor value.
What is electrical impendance?
Impedance (Z) is the vector sum of a circuit's resistance (R) and reactance(X), is expressed in ohms, and is the total opposition to current in an a.c. circuit.Resistance, expressed in ohms, depends upon the length, cross-sectional area, and resistivity of the conductor.Reactance, expressed in ohms, can be inductive reactance (XL), capacitive reactance(XC), or a combination (vector sum) of the two.Inductive reactance is directly proportional to the circuit's inductance and the supply frequency.Capacitive reactance is inversely proportional to the circuit's capacitance and the supply frequency.
Explain the functioning of pBR322 vector with diagram?
FUNCTIONG OF pBR322
What is Impedance for an RLC circuit in series?
1. The RLC series circuit is a very important example of a resonant circuit. It has a minimum of impedance Z=R at the resonant frequency, and the phase angle is equal to zero at resonance.AnswerThe impedance of an RLC circuit is the vector sum of the circuit's resistance, inductive reactance, and capacitive reactance -all of which are expressed in ohms. This applies whether the circuit is at resonance or not.
What is the impedance of a series R-L-C circuit?
the net oppostion offered by the rlc circuit for the ac current to pass through it is called the impedance of rlc circuitAnswerThe impedance of an RLC circuit is the vector sum of the circuit's resistance, inductive reactance, and capacitive reactance, expressed in ohms.
Can anyone explain the burgers circuit burgers vector and define both..?
Ewan.
Is it the impedance value same in AC and DC?
Since impedance is the vector sum of resistanceand reactance, and since reactance is a function of frequency, impedance only really applies to a.c. circuits. You could argue that, in a d.c. circuit, impedance is equal to resistance, but the term really isn't normally used in d.c.
What is induction and inductive reactance?
resistance is real, the other purely imaginary.AnswerResistance is the opposition to the flow of current (AC or DC) which is proportional to a conductor's cross-sectional area and resistivity, and inversely proportional to its length. Reactance is the opposition to AC current due to either the circuit's inductance or its capacitance, and are termed inductive reactance and capacitive reactance. Resistance and reactance are both measured in ohms.Inductive reactance is proportional to the circuit's inductance and the frequency of the supply; capacitive reactance is inversely proportional to the circuit's capacitance and the frequency of its supply. In other words, inductive reactance increases with frequency, whereas capacitive reactance decreases with frequency.All AC circuits contain resistance, and most contain some degree of inductance and/or capacitance. So the opposition offered by a circuit to AC current includes resistance together with some combination of inductive and/or capacitive reactance.It's incorrect to suggest that reactance is 'imaginary'in the every day sense of the word -it exists, so it must be 'real'. In this context, 'imaginary' is a mathematical term that indicates that if resistance and reactance were represented in a vector diagram (called an 'impedence diagram'), then reactance quantity would lie at right-angles to the resistance quantity. For this reason, the overall opposition to current flow, which is called impedance, is not the algebraic sum of resistance and reactance, but the vector sum of the two. So, for example, if a circuit had a resistance of, say, 4 ohms, and its inductive reactance was 3 ohms, then its impedance would be 5 ohms -not 7 ohms.Although we can represent resistance and reactance using a vector diagram (impedance diagram), strictly-speaking the quantities themselves are not vector quantities. The impedance diagram is created as a result of a phasor (vector) diagram representing the current and voltage relationships in the AC circuit.
Why must you add the resistance and reactance of a circuit in series by the phythagorean method in order to find the total impedance?
The resistance and reactance of an a.c. load are determined from the phasor diagram for that load. A phasor diagram is very similar to vector diagram, and represents the voltage drop across the resistive component of the load as being in phase with the load current, and the voltage drop across the reactive component as lagging the load current by 90 degrees. The vector sum of these two voltage drops will equal the value and phase-relationship of the supply voltage.If we now divide each of these three voltages by the supply current, we will converted the phasor diagram into what is called an 'impedance triangle', in which the resistance is represented horizontally, the reactance is represented vertically, and the impedance is represented by the resulting hypotenuse. So, to find the hypotenuse (i.e. the impedance) we must use Pythagoras's Theorem to vectorially-add the horizontal (resistance) and vertical (reactance) components.
What is the impedence?
Impedance is the complex form of resistance. Impedance takes into account capacitance and inductance in a circuit as well. Impedance can be represented as resistance as a function of frequency.See link.AnswerImpedance is not a 'complex form of resistance'. It is the vector sum of a circuit's resistance and reactance. In electrical engineering, 'resistance' has a very specific meaning, and cannot be used to denote 'opposition'.
Does the impedance of an RL series circuit varies inversely with the frequency?
The simple answer is no. The impedance of an R-Lcircuit is the vector sum of the circuit's resistance and its inductive reactance. Resistance is determined by the length, cross-sectional area, and resistivity of the conductor (although its 'a.c. resistance' is proportional to the frequency squared), whereas the inductive reactance is directly proportional to the frequency of the supply.
What is meant by apparent impedance?
You may be mixing up 'impedance' with 'apparent power'.Impedance is the vector sum of an a.c. load's resistance and reactance, and is expressed in ohms. Apparent power is the vector sum of true power and reactive power, and is expressed in volt amperes.Apparent power is also the product of the square of the load current and the impedance of the load.
The total opposition to current in a series RC circuit is called?
Assuming you are talking about an AC circuit, then the total opposition to the flow of current in an R-C circuit is called its impedance (symbol: Z), measured in ohms. This is the vector sum of the circuit's resistance (R) and its capacitive reactance (XC) -each also measured in ohms.
An inductor has an inductive reactance of 64ohm's and a wire resistance of 36ohm's what is the impedance of the inductor?
Impedance is a vector sum using the formula Z = square root (XL2 + R2); where Z = impedance, XL = inductive reactance, and R = resistance. Therefor the formula for a circuit where XL = 64ohm's and R = 36ohm's is Z = square root(642 + 322); Z = 71.6ohms.
