From: tnp@invalid.invalid   
      
   On 10/04/2024 14:16, Chris Green wrote:   
   > Mike Scott  wrote:   
   >> Hi all. Two separate projects which will need a relay of some sort to   
   >> run from a Pi or similar.   
   >>   
   >> I'm really looking for something plug-and-go rather than build-your-own   
   >> (especially item 2 below)   
   >>   
   >> First is a dpdt relay to switch around 12-20 V at a couple of amps. spdt   
   >> are easy to come by; the only dpdt ones I've found are on aliexpress,   
   >> but their longevity is possibly open to question :-{   
   >>   
   > Try CPC (cpc.farnell.com), but you will probably need some sort of   
   > 'driver' between the Pi digital output and the relay coil.   
   > Alternatively, as suggested here, a solid state switch or even an opto   
   > isolator.   
   >   
   >   
   >> Second is something to switch mains safely - a full 13A to run a 3kW   
   >> heater. I've drawn a blank: best I can think of is to butcher one of   
   >> those wireless mains switch modules, which would at least provide a good   
   >> isolation gap :-)   
   >>   
   > Again CPC will probably have something, but again you'll need   
   > something between the Pi and the 'whatever'.   
   >   
   > Are there not ready made relay modules for the Pi?   
   >   
   There are, but most are lower power and SPDT.   
      
   Which is why I built my own...   
      
   BUT although it would be a fun project, even getting hold of big solid   
   state relays is difficult.   
      
      
   --   
   "First, find out who are the people you can not criticise. They are your   
   oppressors."   
         - George Orwell   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)