From: Marco Denicolai
Date: Wed, 27 Jun 2001 09:24:58 +0300
Subject: [TSSP] Toroid breakdown voltage indirect meas.
Hello all, Before getting a discharge to the primary and blowing the CCPS, I was using Thor to measure (indirectly) the voltage required to get streamers from the toroid. I was used to think the threshold value was above 12 kV feed, i.e. 390 kV (calculated from the MicroSim model) but this measurement proves that this value is much higher. This time we were operating in complete darkness, besides some small red warning lights on the safety fence around Thor. The measuremnt was well repeatable, but indirect for two reasons: 1 - I was not directly measuring the feed voltage, but rather its setpoint (i.e. desired value) 2 - I was not directly measuring the secondary top voltage, but calculating it with the MicroSim model of Thor. The voltage predicted by the model, BTW, is the same that what Antonio Carlos program (TeslaSim) predicts. Anyway, here are the results: - Feed voltage 18 kV or less (i.e. toroid 585 kV or less): no streamers, NO CORONA anywhere. - Feed voltage 18.35 kV or more (i.e. toroid 598 kV or more): streamers, NO CORONA anywhere. The toroid had no bumps or sharp sticks applied, as well as there was no grounded rod nearby it. We really couldn'r see any corona on the toroid preceeding leader formation. Of course, the red light were a little glittering on the toroid surface, and the RSG was also making some light (but not much). I would say that the precision of the setpoint (i.e. feed) voltage measurement was within 5-10%. Bang rate was about 300 BPS. This was also the first time we were running in full darkness, instead of being under the light of powerfull halo lamps. Comments? Regards -- _____________________________________________________________ Marco Denicolai Senior Design Engineer Tellabs Oy tel: +358 9 4131 2769 DSL Products mobile: +358 50 353 9468 Sinikalliontie 7 fax: +358 9 4131 2410 02630 Espoo FINLAND email: marco.denicolai@tellabs.com _____________________________________________________________
Maintainer Paul Nicholson, paul@abelian.demon.co.uk.