Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.
One of the simples methods of sensing loads is to use a low-Ω resistor (0.1Ω or less) in series with a load and connect 5/230V transformer with the 5V winding in parallel with this resistor. By doing this you have gain of ≈44, and now this signal can be used by an ordinary comparator to acitvate something (relay, LED, ..) ..
Also, this circuit provides isolation from dangerous mains voltage ..
Regards,
IanP
Attached is your circuit ..
As +12V supply for this circuit you can build a power supply with 7812 voltage regulator in its basic configuration (see attached picture) with 230/12-15Vac transformer ..
Regards,
IanP
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.