[ARC5] BC-442 Relay

Sun, 09 Feb 2003 21:30:16 -0600

The reason I asked about theory is that the thermocouples are connected like 
this:

       RF
     __|__
T/C /     \ T/C
    \_   _/
     _| |_
T/C /     \ T/C
    \_   _/
+ ____| |____ -
T/C /     \ T/C
    \_   _/
     _| |_
T/C /     \ T/C
    \_____/
       |
       RF

4 in series in parallel with another 4 in series.  RF from the current 
transformer is connected to the top and bottom connections as shown and the 
meter is connected in the middle.  It seems that the thermocouples 
themselves are being used as the load.  As the current flows through the 
wire, the thermocouples would heat up and then put out a voltage.  It seems 
an unconventional way of using a thermocouple if this is indeed how it 
works.

Sean

>From: "J. Forster" <[email protected]>
>Reply-To: [email protected]
>To: Sean Barton <[email protected]>, ARC-5 <[email protected]>
>Subject: Re: [ARC5] BC-442 Relay
>Date: Sun, 09 Feb 2003 01:03:00 -0500
>
>Sean Barton wrote:
>
> > Also, does anybody know the theory of operation for this circuit?
>
>I believe the circuit works by converting the output of the RF current
>transformer into heat by running the current through a resistive wire and
>measuring the temperature rise with the thermopile you describe. The 
>thermopile
>output deflects the meter.
>
>-John

_________________________________________________________________
Add photos to your messages with MSN 8. Get 2 months FREE*.  
http://join.msn.com/?page=features/featuredemail