optoisolators

[Foaad]

Hi again, thanks for your response.
Howcome your having a 415V supply? I tried this and I think i blew the chip

AC+ (120V) --- 10k resistor -- Pin 1 of PC814X
AC- --- Pin 2

then i started smelling something.
what do you use the diode for?

Thanks

 

[CBarn24050]

Subject: optoisolators
From: foaadnami@gmail.com (Foaad)
Date: 19/01/2005 03:59 GMT Standard Time
Message-id: <ce15315b.0501181959.1940d424@posting.google.com


I tried this and I think i blew the chip

AC+ (120V) --- 10k resistor -- Pin 1 of PC814X
AC- --- Pin 2


then i started smelling something.

Sounds like the resistor's wattage is to low, it needs to be at least 2W and it
will get hot!

what do you use the diode for?

Diode? what diode?

 

[James Beck]

In article <ce15315b.0501181959.1940d424@posting.google.com>,
foaadnami@gmail.com says...

Hi again, thanks for your response.
Howcome your having a 415V supply? I tried this and I think i blew the chip

AC+ (120V) --- 10k resistor -- Pin 1 of PC814X
AC- --- Pin 2

then i started smelling something.
what do you use the diode for?

Thanks

You will exceed the PIV of the opto diode.

I would go :
AC+(Hot?) ---> 10K resistor (5Watt min) ---> Pin 1 opto
Pin 2 of opto to 1N4004 Diode Anode
Diode Cathode ---> AC-(Neutral?)

The 1N4004 will keep you from blowing the opto during the reverse
voltage portion of the AC waveform.

Jim