• Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

Simple Light Break Detection

spike47

Member
Hi
Am making a light break detection sensor as per attached schematic.

Question: I can't find a 5v relay with a coil resistance of 125 Ohms, I have some 5v relays at 70 Ohms would they work ?, also the diode 1n4004 , I have some 1N5397 would they do in place of the 4004 ? .

cheers
Spike
 

Attachments

spike47

Member
Hi again
Is there some way to introduce a time delay into this circuit, so that after the object passes through the beam break the relay will stay activated for lets say a second later !.

cheers
Spike
 

Pommie

Well-Known Member
Most Helpful Member
Yes. But your question is ambiguous. Do you want the relay delayed or the activation to be extended?

Mike.
 

spike47

Member
Yes. But your question is ambiguous. Do you want the relay delayed or the activation to be extended?

Mike.
Hi
Thanks for your reply, sorry if not been clear, "activation to be extended" is what I would like to do .
heers
Spike
 

wkrug

Active Member
A longer time ago I've realized that with an simple REED Contact.
The Power line to the Bulp was wrapped a few times around the reed contact - Dependend from the drawn current.
When Current to the Lamp was drawn the Contact opens.
When Lamp defect no current was drawn and the control Led lights up.
 

Latest threads

EE World Online Articles

Loading
Top