01-02-2011, 12:06 AM
In electronic ac voltmeters input signal is firstly rectified and then supplied to the dc amplifier. In some circuits, the block diagram includes the attenuator, the rectifier and the multi-stage DC amplifier. and finally the output is shown in the PMMC meter. Sometimes, the block diagram will be attenuator->multistage amplifier, rectifier and PMMC meter.
AC voltmeters are divided into:
Average Reading AC Voltmeters.
They are average responding type and indicates the average value of the voltage on the dial. This method is effective and works satisfactorily and is less expensive beccause most of the systems involves the sinusoidal waveform. But in the case of the non-sinusoidal waveform voltage, the high or low waveform is given depending on the form factor of the waveform.
Implementaation:
Use a 220 to 6 V transformer which is then rectified and filtered to give the 6V dc . To adjust the voltage, a voltage divider circuit is used. Then give it to ADC to use the microcontroller to read the voltage and display in the LCD.
http://8051projectsforum-t31555.html
http://circuitstodayac-voltmeters
AC voltmeters are divided into:
Average Reading AC Voltmeters.
They are average responding type and indicates the average value of the voltage on the dial. This method is effective and works satisfactorily and is less expensive beccause most of the systems involves the sinusoidal waveform. But in the case of the non-sinusoidal waveform voltage, the high or low waveform is given depending on the form factor of the waveform.
Implementaation:
Use a 220 to 6 V transformer which is then rectified and filtered to give the 6V dc . To adjust the voltage, a voltage divider circuit is used. Then give it to ADC to use the microcontroller to read the voltage and display in the LCD.
http://8051projectsforum-t31555.html
http://circuitstodayac-voltmeters
