AVR-Chat

--- In AVR-Chat@yahoogroups.com, "Astria Nur Irfansyah" 
<irfansyah@t...> 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? 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.
> 
> And does anyone know the resistance of a relay?
> 
> Thanks.
> Irfan.

Solid state relays are a fixed device with many variations.  some are 
DC output, others are AC output and BOTH require a load to operate.  
you cannot test one with a meter, but you MUST have it loaded to test.

As far as the inputs, logic, TTL, serial, AC, line voltage... you 
name it.  the idea is that it offers isolation between the signal and 
the load and that it is silicon in that it does not have mechanical 
limitations on wear of the parts and it can operate FAST.

Here is a link to Aromat / NAIS that is a brand name relay company.  
this will offer some of the types of specs for solid state relays.
http://www.aromat.com/pcsd/webpages/ssr_h.htm
http://www.aromat.com/pcsd/ssrtec.pdf

Dave