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???
03/31/05 21:18
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 		 #90776 - Safety issues
Responding to: ???'s previous message
I seem to remember some BASEEFA certified optos - about an inch between pin pairs!
How about making your own from neons and photodiodes, in a length of black heatshrink tube (not UL recognised, but could be made safely)?
I've used standard optos (well 5kv rated) with series X2 capacitor, bridge rectifier and series very low wattage resistor as an ultimate fuse (and a telltale LED) for many years (too many) for industrial 230/115vac plant inputs. Never had a failure (unless you count some VERY early Litronix (1973) optos that suffered from ion migration when energised for days continuously - as you do on failsafe interlocks. When de-energised, they'd take hours to switch off again...Doh!).
The relays you describe are called 'bistable' I think.

List of 37 messages in thread
TopicAuthorDate
Detecting 220V            01/01/70 00:00      
   AC-input optoisolator            01/01/70 00:00      
      Thanks!            01/01/70 00:00      
   I'd use a transformer            01/01/70 00:00      
      Why the transformer?            01/01/70 00:00      
         not necessarily relative to ground            01/01/70 00:00      
            Neon + LDR?            01/01/70 00:00      
      I read the Datasheet of MID400            01/01/70 00:00      
         MID400            01/01/70 00:00      
            That's strange, Erik!            01/01/70 00:00      
               recognized            01/01/70 00:00      
                  "You're Forgiven, Not Forgotten..."            01/01/70 00:00      
   Transformer isolation recommended            01/01/70 00:00      
      May I Modify Your Suggestion Kai ??            01/01/70 00:00      
         Of course...            01/01/70 00:00      
            Kai, Michael - what about ready-made            01/01/70 00:00      
               Could also solve the problem            01/01/70 00:00      
                  One futther on the Wall Wart Idea...            01/01/70 00:00      
                  Wall Wart            01/01/70 00:00      
      Is optoisolation fundamentally dangerous            01/01/70 00:00      
         No, not fundamentally, but...            01/01/70 00:00      
            What is dangerous?            01/01/70 00:00      
   A different view            01/01/70 00:00      
   I'm sweating... ;-)            01/01/70 00:00      
      wallwarts            01/01/70 00:00      
         Oh, I see!            01/01/70 00:00      
            that's a lot of fuses            01/01/70 00:00      
            A bit clarification required            01/01/70 00:00      
               Forgot to press the "Post" button            01/01/70 00:00      
                  enough, yes - that much, no            01/01/70 00:00      
                  Existing commercial products            01/01/70 00:00      
                     Quite a large project, indeed...            01/01/70 00:00      
                        Mains control            01/01/70 00:00      
                           I know...            01/01/70 00:00      
                        Safety issues            01/01/70 00:00      
   Another idea, using a coil and an op-amp            01/01/70 00:00      
      RE: Another idea...            01/01/70 00:00      

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