Skip to main content

Wein bridge

 Wein bridge

Basically, the bridge is used for the frequency measurement but it is also used for the measurement of the unknown capacitor with great accuracy.
Its one ratio arm consists of a series RC circuit i.e. R1 and C1. The second ratio arm consists of a resistance R2. The third arm consists of. the parallel combination of resistance and capacitor i.e. R3 and C3.




Application:

1. The bridge is used to measure the frequency in the audio range. The audio range is [20-200 - 2 k - 20 k] Hz.
2. The resistances are used for the range changing while the capacitors are used for fine frequency control.
3. The bridge can be used for capacitance measurement if the operating frequency is known.
4. The bridge is also used in a harmonic distortion analyzer, as a notch filter and in audio frequency and radio frequency oscillators as a frequency-determining element. 
5. This bridge can readily obtain an accuracy of 0.5 % - 1 %.

Advantage:

1. The Wien bridge can be used to determine unknown frequencies where the device can be calibrated in terms of frequency which can control the balance condition of the bridge.
2. The bridge can be effectively used for the frequency measurement in between 100Hz to 100 kHz range. In most of the practical Wien bridges the accuracy of 0.1 % to 0.5 % can be achieved.
3. In some special purpose applications, the Wien bridge can also be used to determine value of unknown capacitance.

Disadvantage:

1. As the Wien bridge is frequency sensitive, it is difficult to balance it.
2. It requires purely sinusoidal voltage at its input terminals. If the input voltage consists of harmonics, then the true balance point gets masked and the harmonics in the input voltage produce the output voltage.



Comments

Post a Comment

Popular posts from this blog

Analog to Digital Converters: Successive Approximation A/D Converter

  Analog to Digital Converter & Its Working Almost every environmental measurable parameter is in analog form like temperature, sound, pressure, light, etc. Consider a temperature  monitoring system  wherein acquiring, analyzing, and processing temperature data from sensors is not possible with digital computers and processors. Therefore, this system needs an intermediate device to convert the analog temperature data into digital data in order to communicate with digital processors like microcontrollers and microprocessors. Analog to Digital Converter (ADC) is an electronic integrated circuit used to convert the analog signals such as voltages to digital or binary form consisting of 1s and 0s. Most of the ADCs take a voltage input as 0 to 10V, -5V to +5V, etc., and correspondingly produces digital output as some sort of a binary number. What is Analog to Digital Converter? A converter that is used to change the analog signal to digital is known as an analog to digital...
Post a Comment
Read more

Single Channel Vs Multi Channel DAS

  Single Channel Data Acquisition System: A Single Channel Data Acquisition System consists of a signal conditioner followed by an analog to digital (A/D) converter, performing repetitive conversions at a free running, internally determined rate. The outputs are in digital code words including over range indication,  polarity  information and a status output to indicate when the output digits are valid. A Single Channel Data Acquisition System is shown in Fig. 17.3. The digital outputs are further fed to a storage or printout device, or to a digital computer device, or to a  digital computer  for analysis. The popular Digital panel Meter (DPM) is a well known example of this. However, there are two major drawbacks in using it as a DAS. It is slow and the BCD has to be changed into  binary coding , if the output is to be processed by digital equipment. While it is free running, the data from the A/D converter is transferred to the interface register at a rat...
Post a Comment
Read more

Concepts and types of Digital voltmeter

Digital Voltmeter (DVM) Definition : Digital Voltmeter is a  voltage-sensitive device . It  measures AC  or  DC voltage  and  displays  the value directly in  numeric form  instead of pointer deflection.  DVM  is an acronym for  Digital Voltmeter . DVM was first invented in  1954  by  Andrew Kay . There exist many factors that affect the measurement accuracy of a digital voltmeter(DVM). These are basically temperature, input impedance, variation in power supply voltage etc. As we know that an  analogue instrument  provides results by  pointer deflection  on a continuous scale. On contrary, a  digital instrument  provides results as  discrete numerals . Thus providing accuracy and versatility together. The input range of DVM may vary from  ±1 V  to  1000 V . Precision DVM offers  input resistance  of  1 GΩ  or high for a voltage range of less th...
Post a Comment
Read more