Continue to Site

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.

  • 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.

how to build current sensing circuit with timer

Status
Not open for further replies.

tesla2008

New Member
hi there
can anyone tell me how can I build a circuit that would detect when a plasma TV is under load (wakes up) and then turn an light bulb/fluorescent tube 'on' via timer.

the idea is when there is change in power draw due to plasma TV going from "sleep" mode to power mode a current sensing circuit turns on electronics with a relay that then turns a light and holds it in "on" position for say 1/2 hour or so.

input voltage to plasma TV is 120V.
amperage that TV draws when it wakes up is probably in range of 5 A or more
and when in sleep is most likely in single digit watts.

thanks for any suggestions
 
You could use a current transformer on the plasma tv's power cord, use this and a comparator. When the current goes up the comparator output will be pulled up by a pull-up resistor and turn a relay on.
 
Status
Not open for further replies.

Latest threads

New Articles From Microcontroller Tips

Back
Top