Hi,
can someone tell me wat is a zero crossing detector? wat does a simple zero crossing detector consists of??? do anyone have any schematic that can give me??? Sorry for asking so many qns but really need help here. thks.

Regards.

 

With zero-cross switch in AC application You can make noiseless on-off.This mean the load switched off or on when the voltage about zero on it. Most of case optotriacs contains this circuit (MOC 3041).
Here is a primitive sematic for better understandig.

Attached Images

zerocross.GIF (2.7 KB, 461 views)

 

What are you using the detector for? Sebi's right, but if it's just going to be used for timing applications, a true zero-crossing detector isn't necessary. Any circuit that switches at the same point in each AC cycle will work. A voltage divider on a transformers' secondary, followed by schmitt trigger or comparator can generate a square-wave for timing purposes.

 

I have a project which need me to design a zero-crossing detector. Therefore I need to know wat a zero-crossing detector is. is the picture a zero-crossing detector???? My input is a noisy ac voltage and output a digital 5V pulse.

 

Hey I am telling you what I know about simplest Zero Crossing Detector

Zero Crossing detector is a comparator whose reference or threshold voltage (which is applied at one of the two terminals of the op-amp)
is made zero.

It is used to get a perfect square wave from a sine wave.

If a capacitor and a diode with two resistors (another network) are added
at the output of the simple zero crossing detector then pulses are obtained at the output of the network. (The input of the network is the output of ZCD)

 

hi
how this circuit work?
please give some details of the circuit u attached..

 

hi,
I would suggest you start a new thread, this one is 5 years old.!

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