nanog mailing list archives
Re: Wacky Weekend: NERC to relax power grid frequency strictures [OT]
From: Pete Carah <pete () altadena net>
Date: Sun, 26 Jun 2011 18:54:24 -0400
On 06/26/2011 05:55 PM, Jussi Peltola wrote:
On Sun, Jun 26, 2011 at 11:36:24PM +0200, Ingo Flaschberger wrote:but transforming is not easy. ac/ac transformers are easy tu build and very immune against lightning strikes - inverter systems are not.Switching DC is also problematic since there is no zero crossing to extinguish the arc.
Sometime look at break ratings for AC and DC breakers and compare the relative sizes. Shows this effect. Easy answer is: don't use mechanical switches for routine switching... (easy if there is an inverter present, like in a VF drive or switching power supply). Big enough AC breakers maintain the arc over more than one cycle so have this problem too. (plasma quench time at atmospheric pressure can be a while...) Given the technology of the time, AC won rightfully. Still better for most distribution. -- Pete
Current thread:
- Re: Wacky Weekend: NERC to relax power grid frequency strictures, (continued)
- Re: Wacky Weekend: NERC to relax power grid frequency strictures Jason Roysdon (Jun 25)
- Re: Wacky Weekend: NERC to relax power grid frequency strictures Owen DeLong (Jun 25)
- Re: Wacky Weekend: NERC to relax power grid frequency strictures Ingo Flaschberger (Jun 25)
- Re: Wacky Weekend: NERC to relax power grid frequency strictures Seth Mattinen (Jun 25)
- Re: Wacky Weekend: NERC to relax power grid frequency strictures Paul Graydon (Jun 25)
- Re: Wacky Weekend: NERC to relax power grid frequency strictures Andrew D Kirch (Jun 25)
- Re: Wacky Weekend: NERC to relax power grid frequency strictures Joel Jaeggli (Jun 25)
- Re: Wacky Weekend: NERC to relax power grid frequency strictures Ingo Flaschberger (Jun 26)
- Re: Wacky Weekend: NERC to relax power grid frequency strictures [OT] Jussi Peltola (Jun 26)
- Re: Wacky Weekend: NERC to relax power grid frequency strictures [OT] Pete Carah (Jun 26)