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I need a 15kV or higher power supply. I found 2 used neon sign transformers rated at 10kv. Can I use both of them and connect the secondary coils in series to get 20kV?

I am not sure if 15kV isn't overkill. I need voltage that is big enough to ignite a spark between 5-10mm. I read that the value is 30kV/cm, so I assume 15kV is good enough to jump 5mm.

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up vote 3 down vote accepted

Typically high-voltage (and 10kV is high voltage) neon sign transformers have a center-tapped secondary and the midpoint is grounded (MPG). See this reference.

You thus cannot usefully connect the outputs of this type of transformer in series, the output will be partially shorted.

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or you could isolate/disconnect the center taps and ground the connected terminals – ratchet freak Jun 11 '14 at 8:47
@ratchetfreak The insulation would not be reliable even if that was possible. Better (and safer) to buy a 15kV transformer. – Spehro Pefhany Jun 11 '14 at 10:56
This is bad news. What else can I use to get 20kV pulsed DC?! Ignition coil? – Komental Jun 12 '14 at 1:07
10kV transformer, diode and capacitor, but that's almost another question. – Spehro Pefhany Jun 12 '14 at 2:01
@ratchetfreak Can you post an answer about how to do that? I found this link: rtftechnologies.org/emtech/nst.htm – Komental Jun 12 '14 at 14:23

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