[ARC5] Testing BC-442 Thermocouples

[J. Forster]

The "pickup" transformer is an RF Current transformer and essentially a
dead short at 60 Hz

You either need to use RF or disconnect the TC unit from the transformer.

-John

===============



> I have a pair of BC-442 Relay Units on the bench and I’m trying to
> determine if the internal thermocouples are working.
>
> For general testing of RF Ammeters I use my Variac at 20V through a 20 ohm
> series resistor.
>
> I tried that for both Relay Units and I get no meter deflection.  I’m
> tapping directly into the “B” side of the pickup transformer.
>
> I’m suspecting the pickup transformer won’t work at 60 Hz.   I tested the
> meter directly and it works.
>
> Thoughts?   Other ideas how I can test the unit (aside from just putting
> in
> the actual circuit, which I will after I clean up some cruddy relay bypass
> “mods” in them
.)
>
> 73 Mark K3MSB
> ______________________________________________________________
> ARC5 mailing list
> Home: http://mailman.qth.net/mailman/listinfo/arc5
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:ARC5 at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>
>