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Re: Rotary Sparkgap



Re: Current limited transformers
	The current which is limited is the short-circuit
current.  For example, a 12 kV, 60 ma transformer (if it
really limited to 60 ma) would have an equivalent internal
reactance of (12000/0.06) = 200,000 ohms.  The
equivalent inductance would be about 530 henries (assuming
no saturation effects), and for a resistive load the current
would decrease with output voltage, reaching zero at infinite
load resistance.  I started to write that the current would
decrease linearly, but that is, of course, not true.
	Anyhow, a capacitive load on the transformer changes
matters dramatically.  For example, the 530 henry inductance
calculated above would series resonate with an 0.0135 ufd
capacitor, the output current could in principle greatly
exceed 60 ma, the output voltage could (and indeed would) be
much greater than 12 kV with no other load than the capacitor,
and the transformer would probably short out.
	More at some time when I can figure out some real
numbers.
Ed Phillips