X-Virus-Scanned: clean according to Sophos on Logan.com X-SpamCatcher-Score: 30 [X] Return-Path: Received: from [201.225.225.168] (HELO cwpanama.net) by logan.com (CommuniGate Pro SMTP 5.1.6) with ESMTP id 1846919 for flyrotary@lancaironline.net; Mon, 19 Feb 2007 09:47:35 -0500 Received-SPF: none receiver=logan.com; client-ip=201.225.225.168; envelope-from=rijakits@cwpanama.net Received: from [201.224.94.164] (HELO usuario5ebe209) by frontend2.cwpanama.net (CommuniGate Pro SMTP 4.2.10) with SMTP id 101284595 for flyrotary@lancaironline.net; Mon, 19 Feb 2007 10:06:05 -0500 Message-ID: <005001c75434$b96dec90$a45ee0c9@usuario5ebe209> From: "Thomas y Reina Jakits" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] ATC fuses with manual or auto-reset Date: Mon, 19 Feb 2007 09:16:51 -0500 MIME-Version: 1.0 Content-Type: text/plain; format=flowed; charset="Windows-1252"; reply-type=original Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.3028 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3028 Waytek seems to have a LOT of interesting stuff! Just as a sample these hightemp connectors: http://order.waytekwire.com/IMAGES/M37/catalog/219_026.pdf Considering the temps you run on the rotary these may come in handy! Thomas ----- Original Message ----- From: "Chris Sargent" To: "Rotary motors in aircraft" Sent: Sunday, February 18, 2007 6:57 PM Subject: [FlyRotary] ATC fuses with manual or auto-reset > > Waytek sells the ATC fuses below that have either a manual or auto-reset > capability. > > This offers some options to those deciding between circuit breakers or > fuses. > > Link to the Waytek PDF catalog page: > > http://order.waytekwire.com/IMAGES/M37/catalog/219_083.PDF > > > 5-30 Amp, low-profile, manual reset (Type 1) > > 10-30 Amp, manual reset (Type 1) > > 10-30 Amp, auto-reset (Type 3) > > > 5-30 Amp w push-to-trip test feature > > > Regards, > Chris Sargent > > -----Original Message----- > From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net]On > Behalf Of Bulent Aliev > Sent: Sunday, February 18, 2007 7:19 AM > To: Rotary motors in aircraft > Subject: [FlyRotary] Re: CBs and fuses > > In my plane for everything electrical I installed, I asked myself: > can I fly without this item? And accordingly decided on CB or fuse. > A CZ builder had followed the plans and had installed the electric > nose gear fuse in the "per plans" location under the passenger seat. > He takes a passenger for a flight, but on retraction, his nose wheel > is cocked , hits the bottom of the fuselage and pops the fuse. > Something goes wrong with the manual override too. Now he asks the > passenger to unbuckle, turn around and put his butt against the > windshield, so he can replace the fuse while flying the plane at the > same time. If he had spent few dollars on a CB, he could have pushed > it in and flown with the gear down. > Buly > On Feb 18, 2007, at 7:35 AM, Thomas y Reina Jakits wrote: > >> Hi Al, >> >> interesting!! >> >> Next chance I have I will try to find out more about this >> (reasoning for use of fuses over CB's in this helicopter). >> I don't really buy the "repair after trip" -reason as the result is >> the same. >> Whatever caused the fuse or CB to trip, it should be repaired. What >> really happens is that the fuse is replaced - if it doesn't trip >> immediately, no one will look any deeper into it, than a >> "look" (unfortunately...), .... until it trips again. >> A lot of trips can be caused by changing environment (heat, >> humidity, etc.) that bring the conditions for over current just to >> the trip point, but will not under normal conditions. >> However I am no specialist, not even building anything at this time >> - so, I will try to find out for this specific application (AS350B3) >> >> Thomas >> >> PS: First thing I am going to do is to consult the Maintenance/ >> Repair manual.... >> ----- Original Message ----- >> From: Al Gietzen >> To: Rotary motors in aircraft >> Sent: Saturday, February 17, 2007 6:10 PM >> Subject: [FlyRotary] CBs and fuses >> >> >> Eurocopter Factory Instructors are VERY COMPETENT in Eurocopter >> Helicopter Systems!! >> >> There is absolutely NO doubt that he knows the difference between >> fuses and breakers and WHY either one would be used. >> >> >> Thomas; >> >> Certainly not impugning the competence of the flight instructors; >> just suggesting the design engineers may have other reasons than >> cost. One may be reliability. The reliability of CBs goes down >> significantly after they have experienced a 'trip'. I recall >> reading one experts opinion that a CB should be replaced after a >> 'trip'. Yeah; seems extreme. The modern philosophy of circuit >> design is to design for fault tolerance, so a fault; once causing >> the protection device to open, is left for repair when you land. >> >> >> The key for using fuses is fault tolerant circuit design and proper >> selection and sizing of fuses. Having done this; studies suggest >> that the fuse offers higher reliability and lower cost. >> >> >> There certainly reasons for either CBs or fuses, and I have both in >> my plane. For my flight critical circuits I opted for simple, >> fault tolerance and fuses. I wouldn't argue with someone making a >> different choice. >> >> >> FWIW, >> >> >> Al >> >> > > > -- > Homepage: http://www.flyrotary.com/ > Archive and UnSub: http://mail.lancaironline.net/lists/flyrotary/ > > > -- > Homepage: http://www.flyrotary.com/ > Archive and UnSub: http://mail.lancaironline.net/lists/flyrotary/