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A protective relay determines frequency of an AC signal of an electric power system. The protective relay includes a circuit measuring the AC signal period between zero crossings to provide a measured period value. A microprocessor includes a random access memory having a five-element array, which collects five consecutive values of the measured period values. A microprocessor routine chooses a median from the measured period values and generally determines the frequency based upon the median. The median is ignored and the previously determined line cycle period is adjusted to determine the new line cycle period if: an absolute value of a difference between a last value of the measured period values and a previously determined line cycle period is not less than a predetermined value; and the last value of the measured period values is within the limits of the array. <Prof Dae_Pwa>
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-if the period of one cycle of an AC signal is 20mS what is its frequency?
50 cycles
Why the linear combination of a low frequency intelligence signal and a high frequency carrier signal is not effective as a radio transmission?
to shift the frequency of information signal ,at the frequency domain to a higher frequency ...so the information can be transmitted to the receiver.
What is the Difference between frequency converter and frequency inverter?
frequency is genrally cycle per second, and frequencies may be of a dc nature or ac , devices which convert dc frequency in to an ac frequency are frequency converters and devieces which convert ac frequency in to dc frequency are frequency inverters. because in terms of power electronics, devices which convert ac to dc are called converters, and devices which convert dc in to ac are called "inverters" 'mehboob hunzai" I'm a engineers in this devices, the frequency inverter is convert AC to AC but with variable frequency output, means the frequency & voltage are adjustable; The frequency converter can convert DC to AC, like 24VDC to 220VAC and also the frequency is adjustable. One most important thing is the out power of frequency inverter just can be used for controlling AC motor, while frequency converter can be treated as normal power supply as our daily using power grid. "zhuge fs"
What is IP3 and IM3?
IM3 degrades the sensitivity of the desired signal as an in band spurious frequency component. IP3 determines the severity of the degradation as a measurement through the linearity of the system.
What does frequency of a signal measure?
repetition rate of signal
Which element of an electric signal determines its capacity to carry information?
Frequency
What determines the output frequency of an ac generator?
It's speed and the number of poles.
What determines the amount of deviation of an fm signal?
FM or frequency modulation is a means to vary the frequency withing a set basic frequency and transmit it. FM radio demodulate the frequency extracting the signal that made the frequency shift at the source.
What is a cycloconverter?
A cycloconverter or a cycloinverter converts an AC waveform, such as the mains supply, to another AC waveform of a lower frequency, synthesizing the output waveform from segments of the AC supply without an intermediate direct-current link.
What determines the speed of an AC motor?
The higher the frequency the higher the RPM the motor will turn
-if the period of one cycle of an AC signal is 20mS what is its frequency?
50 cycles
What is the relation between amplitude and freq if a transmitter having frequency 500mhz what is the amplitude range if have any formula please tell me about that?
Actually the amplitude depends on your modulator by which you generated your signal you can pick any amplitude you want but here is the formula for frequency modulated signal: Ac here decide the amplitude of the signal and you can see that it is not related to the frequency component of your signal.
What determines the frequency ( color ) of photons?
Frequency determines color. Frequency is determined by the origin of the photon, i.e. emitted from an excited atom.
How an electronic transmitters work?
A transmitter takes in a signal and modulates a carrier wave to send that signal out. A mixer takes the signal and modifies it according to the type of transmission being done. AM means amplitude modulation. The signal determines the intensity of the transmitter signal. FM means frequency modulation. The transmitters frequency is changed by the incoming signal.There are several ways of sending a signal. Side band and other methods you can read about.
Comparison of amplitude modulation and frequency modulation?
Amplitude of the (high frequency) Carrier signal is varied with respect to low frequency of message signal is called amplitude modulation. Frequency of the carrier signal is varied with respect to low frequency of message signal is called frequency modulation.
What determines the frequency?
frequency arrived at by moment ,and reciprocal
When low frequency signals added to high frequency signal then the envelope signal will follow which signal?
the low frequency signal which is nothing but the message signalNeither. The envelope will be that of the difference beat frequency. To get the envelope to follow the low frequency input signal you need to mix (multiply) the two signals, not add them.
