Re: Transformers with welded laminations

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: FIFTYGUY@xxxxxxx 

In a message dated 1/30/06 12:41:20 PM Eastern Standard Time, 
tesla@xxxxxxxxxx writes:

> I have come across several misc high voltage transformers with a thin welded
>stripe shorting all the laminations together.  Why would the manufacturer do
>this since it will cause eddy currents? These transformers also had
>(coincidently?) magnetic shunts.

    Cheaper and easier than alternating the laminations to assemble. 
Obviously not as good on the leakage flux. Don't think the eddy 
current issue is too bad, since the laminations are only joined at 
two small small places (still relatively high electrical resistance 
for any eddy currents).
    I've seen this a lot on ballasts for HID lighting, and on a few 
small control transformers. OTOH, it makes it easy to disassemble the 
transformer if you're going to rewind it.

-Phil LaBudde