8051 Interface to control high power devices.

[vamanan]

Dear Friends,
I want to make a load that runs in 220V mains on and off at certain time.
I already wriiten the codes for that.But I dont know how to interface the port pins to control the load that user 220V mains.My code is making the the port pin on and off as requires.Please inform me hoy to connect the port pin to the high current load.
Thanking you.

 

[IanP]

You haven't indicated which microcontroller form 8151 family is going to be used and which pin is going to be used as a switch .. some pins can not pull-up without external resistors ..
One option will be to use a MOC3020-series optocoupler (or similar) and a Triac as a switch .. and even better option will be to choose an optocoupler with zero-crossing feature, or to employ a solid state relay to do the power switching ..
or use an ordinary transistor and drive a relay ..
Regards,
IanP

 

[vamanan]

Dear IanP,
I am using 8051 rd2 philips controller
I am using port1.0 pin for switching on/off. I am planning to use relay for the switching.Can you suggest the schematic for the same.
Thanx

 

[IanP]

For examples goto:
**broken link removed**
See section: Parallel Port Relay Interface .. You should add a 4.7kΩ, or less, resistor between this pin and Vcc .. depending on the transistor type ..
Ragards,
IanP

 

[eng_ahmed22]

hi,
also try this, I thinl it is useful: **broken link removed**
bye
Eng_ahmed22