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Ballasting for pole pig/Many questions



Original poster: "harvey norris by way of Terry Fritz <twftesla-at-qwest-dot-net>" <harvich-at-yahoo-dot-com>

I am entirely unfamiliar with ballasting requirements
for a 15 k pole pig. I understand that the current
must be limited on the primary side, correct? Since
two 150 volt variacs  are available can I use two of
these in series for a control of a 240 volt input by
simultaneously increasing current for both variacs?

I also have several large 3 phase transformers, would
it be better to use their primaries or secondaries as
ballast? Would I be limited to only using one of the
phases or could two in series be used? Forgive the
many questions, this is new territory here for me.

I also have an air core inductance system of .15 henry
consisting of thirty 14 gauge, 500 ft coils in series
that comes to approximately 40 ohms, but if these as
just coils were used wouldnt that limit the current to
that made by the impedance of the .15 henry coil
system? Wouldnt that lower the current input lower
than what my needed requirements for primary current
at the pole pig would be? Using X(L)=2 pi(Freq)L=56.5
ohms would that not limit the current input to some ~
240/56.5= 4.24 amps/ where this pole pig should easily
handle twice that amperage as primary input. Is it
safe to say that 14 gauge wire is a poor choice for a
ballasting wire, as one shouldnt want more than 8 amps
conduction through this wire for ballasting. This
could be done by merely using half of the coils.

Since we are limiting current by addition of
reactance, why couldnt capacitive reactance be used
instead? Is there usually a problem with a capacitive
reactance resonating with the inductive reactance of
the pig primary, thus establishiong more current
conduction and not less?

What about placing cap banks in parallel instead of
series for a sort of power factor correction for the
pig. Would this not be the best approach? Finally
should I use the KVA rating to establish the maximum
allowable amperage consumption for the primary?

Thanx for any replies, I am in the dark on this
subject... HDN

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Binary Resonant System  http://members3.boardhost-dot-com/teslafy/

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