[TowerTalk] New power line phenomena problem

Peter Larsen ve6yc at shaw.ca
Fri Jan 23 18:29:57 EST 2004


 >This is a common misconception, but anyone with any basic knowledge knows
 >that although the electricity drops onto the fence, it's only the voltage
 >part.  

Sorry, but this is wrong.
What is happening is called "induction"
This is the same thing that your transformer does. 
Volts per turn is the formula for changing from a high voltage to
a low voltage.

138000 volts on the primary side, 8000 volts on the secondary 
side, you need a conversion of 17.25. So your 138 KV primary  needs 
17.25 times as many turns as your 8 KV secondary.

Many people have died from induction. I have worked on a 138 KV line
that was dead and grounded 10 feet either side of me. But it was within 
20 feet of a live line. Without the grounds I would have been killed or at
a minimum very badly burnt. It was so "hot" in my bucket that sparks were
going between my tools.

So if you want to power your big amps, just take a large number of
grader blades (this will be your core) wind common bi-plex around
them until you have 120 volts across each winding. Connect the
windings so they are additive and there you go.
Voltage regulation will be poor depending on how much power is
flowing in the HV over head line and how many amps you are pulling
from your home brew transformer.

(I didn't tell you to do this, and I will disavow any knowledge of your 
actions ;-)

Peter
VE6YC
25 years as a lineman 



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