Re: Transformer Question

To: tesla-at-pupman-dot-com
Subject: Re: Transformer Question
From: Esondrmn-at-aol-dot-com
Date: Wed, 18 Sep 1996 17:06:47 -0400

In a message dated 96-09-17 00:44:28 EDT, you write:

<< 
 I've been using two 4500VAC 400ma plate transformers pulled from copy 
 machines. These transformers (GE) have an extra winding that is 
 connected to a 660VAC 10uf capacitor.
 
 Questions: What is the purpose of this capacitor? Power factor 
 correction? Current limiting? What effect would result by changing or 
 removing the capacitor?
 
    0---------) || (----------0
              ) || (
   LV In      ) || (
              ) || ( 
    0---------) || (
                || (
     |--------) || (   HV Out
     |        ) || (
    ---       ) || (
    --- 10uf  ) || (
     |        ) || (
     |--------) || (-----------0
 
 Thanks...   ...Jeff Parisse >>


Jeff,

I am not a transformer expert but I have repaired many 36 volt DC 30 amp
battery chargers.  Most are built by Lester Electrical.  They also have a
high voltage winding like the one you have shown with a 6 mfd capacitor
across it.  This winding and cap provides some means of regulation for the
low voltage output.  I had a charger in here last week with the capacitor
shorted.  The low voltage output was zero.  With a good capacitor, the
voltage across the cap is about 750 volts AC with no load on the charger and
about 500 volts AC with a 25 amp load.

If someone can explain how this circuit works, I am also curious.

Ed Sonderman