Ammeter readings with MOT power supply

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Original poster: "Breneman, Chris" <brenemanc@xxxxxxxxxxxxxx>

Hello,

I've almost finished the MOT power supply for my first Tesla coil, 
but have a few questions about its operation.  The supply consists of 
two MOTs with the primaries in parallel and secondaries in series and 
a third MOT in series with the parallel arrangement of the first two 
acting as a ballast.  The ballast has its high voltage winding 
shorted.  All of them run on 120V.  In addition to the transformers, 
I also have a 15A circuit breaker in series with the circuit, and the 
house has its own 15A breaker on this circuit.
I recently received a 15A analog panel ammeter which I wanted to use 
in the circuit to monitor current drawn.  It is placed in series 
between the breaker and the ballast.  When I run the power supply 
with the hv end shorted, no breakers trip, but the ammeter reads off 
the scale.  When I replaced the analog meter with a digital 
multimeter capable of reading up to 20A, it read "Overload".  What I 
don't know if if more than 15A is really flowing, and if it is, why 
it isn't tripping the breakers, and if it isn't, why do the meters 
show that it is?
The only possible cause I can think of for this discrepancy is that 
the power factor is probably greatly offset by the highly inductive 
load, but why wouldn't the breakers trip in this case?  I also tried 
the circuit with a 10uF PFC capacitor, and saw no difference in 
behavior.  If the problem is the power factor, do you think a 180uF 
PFC capacitor would be reasonable for such a supply?  The open 
circuit voltage is slightly over 5kV and the short circuit current is 
slightly over 500mA (that is, assuming these readings from the 
digital multimeter are correct; I determined these values indirectly 
by measuring current through different resistances on the hv side).

Thanks a lot,
Chris