AVR-Chat

At 10:54 PM 8/11/2004, Astria Nur Irfansyah wrote:

>I am not familiar with solid state relays. Btw, which is 
>more important: current or voltage? I mean, what are the 
>requirements in order to close a relay? Enough voltage? or 
>enough current? 

Current. Magnetic flux is amp-turns. Voltage is incidental, and forced by the resistance of the coil.

>As far as i know, if i want to buy  a 
>relay at my favorite store, they will ask: how many volts? 
>My point is, is there enough voltage to turn on your 
>relay? In your circuit, the relay gets less than 5 volts.

The only reason you need voltage, is to overcome the resistance, and get enough current flowing.

>And does anyone know the resistance of a relay?

Yes. :)   The maker, and the data sheet.