Re: High Temp Caps and Inductors
I read in !emc-pstc that Jacob Schanker schan...@frontiernet.net wrote (in 005b01c1e8a8$183598c0$3579d...@frontiernet.net) about 'High Temp Caps and Inductors', on Sat, 20 Apr 2002: I used fiberglass, but although I haven't checked, I don't think that will work at 180C. Possibly Teflon (expensive) or maybe Delrin. Porcelain was widely used (but not at 180 C) 60 years and more ago. Porcelain tubes are already available for power resistors, but you can wind copper wire on them! -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
RE: High Temp Caps and Inductors
Take a look at multi-layer ceramic capacitors from American Technical Ceramics. I used to buy 1.5 uF discoidal models (about 5/8 diameter by 1/8 thick) from them. I imagine that they now have rectangular surface-mount multi-layers capacitors now. Ed Ed Price ed.pr...@cubic.com Electromagnetic Compatibility Lab Cubic Defense Systems San Diego, CA USA 858-505-2780 (Voice) 858-505-1583 (Fax) Military Avionics EMC Services Is Our Specialty Shake-Bake-Shock - Metrology - Reliability Analysis -Original Message- From: John Woodgate [mailto:j...@jmwa.demon.co.uk] Sent: Friday, April 19, 2002 11:49 PM To: emc-p...@majordomo.ieee.org Subject: Re: High Temp Caps and Inductors I read in !emc-pstc that lfresea...@aol.com wrote (in 194.5bfc605.29f1e f...@aol.com) about 'High Temp Caps and Inductors', on Fri, 19 Apr 2002: I'm looking for Ceramics, 0.01 through 1 microfarad. Inductors, 1 to 100 microhenry, about 0.5 amps. You will not, I think, get ceramic capacitors in that value range that keep anything like their low-temperature value at 180 C. You probably need to look at glass-dielectric, but AFAIK a 1 uF glass cap would be physically very large. The normal core materials for inductors in that value range may well be near or above their Curie temperatures, too, so permeability values will be low and very temperature-sensitive. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! --- --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
RE: High Temp Caps and Inductors
Just to keep the record straight, Kapton is a polyimide, not a polyamide. They are vastly different. Polyamide is the general name for the family of polymers commonly referred to as Nylon. Bob Wilson TIR Systems Ltd. Vancouver. -Original Message- From: Scott Lacey [mailto:sco...@world.std.com] Sent: April 21, 2002 6:22 AM To: lfresea...@aol.com Cc: emc-p...@majordomo.ieee.org Subject: RE: High Temp Caps and Inductors Derek, You might try Texas Components (www.texascomponents.com) for high temperature capacitors. They claim usage up to 200 C. I suspect you will have to build (or have built) the inductors. You might check with Dupont to see if Kapton (a high-temperature polyamide) would be suitable for cores. You will also need to obtain magnet wire with suitable insulation, and I suspect that you will have to either weld or silver solder the interconnections. Once you have determined the materials choices any good custom magnetics house should be able to produce the inductors in quantity if needed. Good Luck, Scott Lacey -Original Message- From: owner-emc-p...@majordomo.ieee.org [mailto:owner-emc-p...@majordomo.ieee.org]On Behalf Of lfresea...@aol.com Sent: Friday, April 19, 2002 5:19 PM To: emc-p...@majordomo.ieee.org Subject: High Temp Caps and Inductors Hi all, I'm designing a filter that has to live and work with an Ambient temp of 180 C. Does anyone have suggestions as to component vendors that I could contact for parts? Thanks, Derek Walton. L F Research
Re: High Temp Caps and Inductors
Derek, having previously worked for a filter manufacturer, I was involved with a feedthrough filter design for working up to 150C. A few comments based on the discussion so far: Working Voltage: this has not been mentioned, but considerable de-rating over room temperature ratings will probably be required. Low working voltages, a few Vdc, shouldn't be a problem. Inductor Core Materials: a glance at the Fair-Rite catalogue shows several materials with negligible change in room temp permeability up to 300C: e.g. materials 61, 65,67 68 Solders: somebody mentioned the need to weld, or silver solder. This shouldn't be necessary - 96S solder for example has a melting point of about 221C (96% tin, 4% silver), and is quite usable. Epoxy Seals: feedthroughs are commonly sealed with expoy encapsulants, and these are available with wide operating temperature ranges. BUT, temperature cycling has considerable effect, and can easily cause cracks in the sealant. So, it may be equally important to consider a) what is the minimum operating temperature, and b) how many times will the filter have to go from minimum temperature to 180C and back. The same consideration applies to an encapsulated inductor. Repeated temp cycling can be a real killer! Regards, Jeff Chambers - Dr Jeff Chambers Westbay Technology Ltd Suppliers of EMC Design Software Tel: +44 1229 869 108 Fax: +44 1229 869 108 http://www.westbay.ndirect.co.uk/westbay1.htm j.chamb...@ndirect.co.uk Main St Baycliff Ulverston Cumbria LA12 9RN England - - Original Message - From: lfresea...@aol.com To: emc-p...@majordomo.ieee.org Sent: 19 April 2002 21:19 Subject: High Temp Caps and Inductors Hi all, I'm designing a filter that has to live and work with an Ambient temp of 180 C. Does anyone have suggestions as to component vendors that I could contact for parts? Thanks, Derek Walton. L F Research --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
RE: High Temp Caps and Inductors
Derek, You might try Texas Components (www.texascomponents.com) for high temperature capacitors. They claim usage up to 200 C. I suspect you will have to build (or have built) the inductors. You might check with Dupont to see if Kapton (a high-temperature polyamide) would be suitable for cores. You will also need to obtain magnet wire with suitable insulation, and I suspect that you will have to either weld or silver solder the interconnections. Once you have determined the materials choices any good custom magnetics house should be able to produce the inductors in quantity if needed. Good Luck, Scott Lacey -Original Message- From: owner-emc-p...@majordomo.ieee.org [mailto:owner-emc-p...@majordomo.ieee.org]On Behalf Of lfresea...@aol.com Sent: Friday, April 19, 2002 5:19 PM To: emc-p...@majordomo.ieee.org Subject: High Temp Caps and Inductors Hi all, I'm designing a filter that has to live and work with an Ambient temp of 180 C. Does anyone have suggestions as to component vendors that I could contact for parts? Thanks, Derek Walton. L F Research
Re: High Temp Caps and Inductors
Derek: You obviously are facing a challenge (a.k.a. problem). Sometimes you actually have to make things yourself, and this may be one of those times. For the inductors, I'd say you will have to go with air core. I've done air core inductors up to the hundreds of microhenries (for LF antenna couplers) but we are talking big - 6 inch diameter by 18 inch length. I was also looking for high unloaded Q, which also influenced the size. But even with air core, you still have problems with the coil former and wire insulation. I used fiberglass, but although I haven't checked, I don't think that will work at 180C. Possibly Teflon (expensive) or maybe Delrin. For capacitors, you could go back to basics and make your own, with metal plates and dielectric. How about depleted Uranium for the plates, and Gandolinium dioxide for the dielectric? -( ;) Jack Jacob Z. Schanker, P.E. 65 Crandon Way Rochester, NY 14618 Phone: 585 442 3909 Fax: 585 442 2182 j.schan...@ieee.org - Original Message - From: lfresea...@aol.com To: emc-p...@majordomo.ieee.org Sent: Friday, April 19, 2002 5:19 PM Subject: High Temp Caps and Inductors | Hi all, | | I'm designing a filter that has to live and work with an Ambient temp of 180 | C. Does anyone have suggestions as to component vendors that I could contact | for parts? | | Thanks, | | Derek Walton. | L F Research | --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
Re: High Temp Caps and Inductors
I read in !emc-pstc that lfresea...@aol.com wrote (in 194.5bfc605.29f1e f...@aol.com) about 'High Temp Caps and Inductors', on Fri, 19 Apr 2002: I'm looking for Ceramics, 0.01 through 1 microfarad. Inductors, 1 to 100 microhenry, about 0.5 amps. You will not, I think, get ceramic capacitors in that value range that keep anything like their low-temperature value at 180 C. You probably need to look at glass-dielectric, but AFAIK a 1 uF glass cap would be physically very large. The normal core materials for inductors in that value range may well be near or above their Curie temperatures, too, so permeability values will be low and very temperature-sensitive. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
RE: High Temp Caps and Inductors
A lot depends on the frequency you are operating at. A low frequency filter may use electrolytic caps, for example, and there is no way you will ever get 180°C electrolytics! Most of the common non-electrolytic capacitor dielectrics won't have a hope of operating at this temperature either. Maybe if you clarify the type and frequency of the filter... You are also at or above the melting point of normal tin-lead solder, so that is going to make things just a tad difficult. Bob Wilson TIR Systems Ltd. Vancouver. -Original Message- From: lfresea...@aol.com [mailto:lfresea...@aol.com] Sent: April 19, 2002 2:19 PM To: emc-p...@majordomo.ieee.org Subject: High Temp Caps and Inductors Hi all, I'm designing a filter that has to live and work with an Ambient temp of 180 C. Does anyone have suggestions as to component vendors that I could contact for parts? Thanks, Derek Walton. L F Research
Re: High Temp Caps and Inductors
In a message dated 4/19/02 5:01:40 PM Central Daylight Time, j...@jmwa.demon.co.uk writes: It might be helpful to have an idea of what sort of filter and what frequencies are involved, also the permissible deviations from the ideal response. I'm looking for Ceramics, 0.01 through 1 microfarad. Inductors, 1 to 100 microhenry, about 0.5 amps. Derek.
Re: High Temp Caps and Inductors
I read in !emc-pstc that lfresea...@aol.com wrote (in d3.a31f9f9.29f1e...@aol.com) about 'High Temp Caps and Inductors', on Fri, 19 Apr 2002: Hi all, I'm designing a filter that has to live and work with an Ambient temp of 180 C. Does anyone have suggestions as to component vendors that I could contact for parts? It might be helpful to have an idea of what sort of filter and what frequencies are involved, also the permissible deviations from the ideal response. Otherwise, try hww.satan.com and Beelzebub Electronics Inc. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
High Temp Caps and Inductors
Hi all, I'm designing a filter that has to live and work with an Ambient temp of 180 C. Does anyone have suggestions as to component vendors that I could contact for parts? Thanks, Derek Walton. L F Research
