Don, In this instance we are operating in the range from 200-800 kHz; the output is used in a plasma process and so after ignition it will be from 800V to possibly 1500V depending on the chemistries. The concrete idea was going to be used for mounting purposes and also as a coil form. The engineer found that the permeability and dielectric constant was okay for his application (there's a couple of parameters no one brought up in this thread so far). For his purposes this engineer views the concrete as nearly non-permeable and almost equivalent to an air-core inductor. The windings need to carry several hundred amps of peak current at the resonant switching frequency. The concrete inductor core is similar to a torus with a major diameter of about 12-14" and a minor diameter of about 4". The winding are wrapped with 4" flat braid in sleeving. It just seems that there should be another substance that is more suited to the application without getting into a lot of expense.
Don't know if this changes the discussion but it will be interesting to see what else comes out of this thread. -doug ======================================= Douglas E. Powell, Compliance Engineer Advanced Energy Industries, Inc. 1625 Sharp Point Dr. Fort Collins, Colorado 80525 USA --------------------------------------- 970-407-6410 (phone) 970-407-5410 (e-fax) mailto:doug.pow...@aei.com http://www.advanced-energy.com ======================================= -----Original Message----- From: Don Diego [mailto:zorro_1...@yahoo.com] Sent: Monday, August 23, 1999 5:34 PM To: Egon H. Varju; EMC-PSTC Subject: RE: Concrete as an insulator??? Doug, It sounds to me like this may be a good time to supply more information to the group. High power, 200 kW, at what frequency? Are we talking 13.56 MHz, 27.12 MHz, 40.68 MHz or are we discussing 18 GHz? Just thought that this may change the discussion a tad. --- "Egon H. Varju" <e...@varju.bc.ca> wrote: > > > >Just to add a bit of trivia to this discussion, > concrete increases > >substantially in conductivity in the presence of > ionizing radiation (x-rays, > >gamma rays). This is well known and documented in > the nuclear hardening > >community. This is an indication of an inherent > population of free charge > >carriers in concrete (be they water-based, or > other). > > Hmm ... So, not only will we have to keep the > garden hose away from that > 200 kW power supply, but it may also need a warning > label: "FOR USE ONLY > IN NUCLEAR-FREE ZONES." > > Egon :-) > > __________________________________________ > > Egon H. Varju, PEng > E.H. Varju & Associates Ltd. > North Vancouver, Canada > > Tel: 1 604 985 5710 HAVE MODEM > Fax: 1 604 273 5815 WILL TRAVEL > > E-mail: e...@varju.bc.ca > var...@csa.ca > __________________________________________ > > --------- > This message is coming from the emc-pstc discussion > list. > To cancel your subscription, send mail to > majord...@ieee.org > with the single line: "unsubscribe emc-pstc" > (without the > quotes). For help, send mail to ed.pr...@cubic.com, > jim_bac...@monarch.com, ri...@sdd.hp.com, or > roger.volgst...@compaq.com (the list > administrators). > > > __________________________________________________ Do You Yahoo!? Bid and sell for free at http://auctions.yahoo.com --------- This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to ed.pr...@cubic.com, jim_bac...@monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). --------- This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to ed.pr...@cubic.com, jim_bac...@monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
