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Re: [Phys-l] Step down transformer trouble




I brought my multimeter in to school during out circuits unit. I can't check much right now.
The doorbell remains off. House power appears fine (all branches connected to the same line are behaving normally). That makes me think you're probably right with the secondary coil failure.
In terms of wiring: the transformer has 3 wires coming out if it. One green for ground, and two black. Two black wires is odd, but makes some sense in this application. One black wire is connected to a house black (hot). The other transformer black lead is connected to the house white (neutral) wire.

Paul Lulai
Physics Teacher
St Anthony Village Senior High
3303 33rd Ave
St Anthony Village MN 55418

(w) 612-706-1146




----- Reply message -----
From: "chuck britton" <cvbritton@mac.com>
Date: Wed, Jul 6, 2011 10:55 am
Subject: [Phys-l] Step down transformer trouble
To: "Forum for Physics Educators" <phys-l@carnot.physics.buffalo.edu>

What's the failure mode? (open secondary would be my guess)?

I don't follow the sentence on 'gounding'.


At 5:58 AM -0400 7/6/11, 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?
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