Re: [Phys-l] Step down transformer trouble

[Roger Haar <haar@physics.arizona.edu>]

Dear Paul,

	A bunch of questions:

1.) Had it been working for a while and
then failed or is the door bell new and
never worked right?

1 1/2.) Does the transformer fail immediately
on being placed in the circuit?

2.) Any new electrical work in the house?

3.) Have you checked the doorbell switch(s)
 circuit to see if the the resistance is
 basically infinite when the button is not
 pushed?

4.)  Is it a simple door bell circuit?  That
 is it a simple loop of the secondary the
 switch the bell and back to the secondary.

5.)  Have you tried installing just the primary
side of the transformer for a while to see if
it blows the transformer with nothing on the secondary?

6.)  Does the current rating of the transformer
match the current rating of the bell?

Thanks,
  Roger
========================================
On 7/6/2011 8:37 AM, Dr. Keith S. Taber wrote:
> Just a thought, but is the 16V measured on open circuit, or when the
> bell is connected up?
>
> Keith
>
>
>
> At 05:58 -0400 6/7/11, Paul Lulai wrote:
> > Hi.
> > We can't keep our doorbell stepdown transformer working.  I thought
> > i would check this group for thoughts.
> > The transformer drops to 16v.  That matches the input for our
> > doorbell. The transformer is connected to ground and both the black
> > and white house wires (as directed on installation instructions).
> > It is installed onto a standard junction box with (which has a cfl
> > attached).
> > I've changed transformers multiple times.  I checked the doorbell.
> > I found no problem, but thought a $20 change of bells might so it,
> > so I changed it anyway (after the 2nd transformer).
> > Any thoughts?
> >
> > Paul Lulai
> > Physics Teacher
> > St Anthony Village Senior High
> > 3303 33rd Ave
> > St Anthony Village MN 55418
> >
> > (w) 612-706-1146
> >
> >
> > _______________________________________________
> > Forum for Physics Educators
> > Phys-l@carnot.physics.buffalo.edu
> > https://carnot.physics.buffalo.edu/mailman/listinfo/phys-l