X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from [24.25.9.103] (HELO ms-smtp-04-eri0.southeast.rr.com) by logan.com (CommuniGate Pro SMTP 4.3c5) with ESMTP id 933302 for flyrotary@lancaironline.net; Thu, 05 May 2005 07:59:57 -0400 Received-SPF: pass receiver=logan.com; client-ip=24.25.9.103; envelope-from=eanderson@carolina.rr.com Received: from edward2 (cpe-024-074-189-178.carolina.res.rr.com [24.74.189.178]) by ms-smtp-04-eri0.southeast.rr.com (8.12.10/8.12.7) with SMTP id j45Bx9L5007277 for ; Thu, 5 May 2005 07:59:09 -0400 (EDT) Message-ID: <001801c55169$dd14c8f0$2402a8c0@edward2> From: "Ed Anderson" To: "Rotary motors in aircraft" References: Subject: Mismarked Fuse?? was [FlyRotary] Re: To Fuse or not to Fuse Date: Thu, 5 May 2005 07:59:16 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0015_01C55148.55CC6180" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2180 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 X-Virus-Scanned: Symantec AntiVirus Scan Engine This is a multi-part message in MIME format. ------=_NextPart_000_0015_01C55148.55CC6180 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Hi Paul, You loose nothing by having a reset possibility - something you do not = have with a fuse. Those of use who have successfully reset a CB and = regained a system just have a hard time understanding why anyone would = want to forego the possibility of being able to regain a critical = system. True, it may not work every time or even most times, but its = worked enough times for me and others (such as yourself) to make it a = viable choice. Like I say I use fuses - just not on flight critical = systems. =20 However, for those who decide to use fuses, I think your discovery of = apparently a apparently mismatched fuse should be something they add to = their check list when installing/replacing fuses. I suppose if you use a = different metal as the fuse link (I don't have any ideal which alloy is = used) then you might could use a thinner link - but I would think the = alloy would be pretty standard. But, Like you said could have been = made in China on a Monday or Friday or someone hired a color-vision = impaired person to put the caps on{:>). Good detective work! Ed ----- Original Message -----=20 From: Paul=20 To: Rotary motors in aircraft=20 Sent: Thursday, May 05, 2005 12:29 AM Subject: [FlyRotary] Re: To Fuse or not to Fuse Hi, Ed....thanks for the links. After successfully resetting fuses in = military aircraft, I feel more comfort in knowing that I at least have = the option to reset or not to reset. In one case, it was the landing = gear motor on a King Air that got pretty hot during touch-and-go's = during a checkride. Once the motor cooled, the circuit breaker was = successfully reset, and we were able to lower the gear. I am replacing = my fuel pump fuses with CB's. Anyway, the purpose of this email is to comment on the fuse that = blew on my fuel pump circuit. We looked at it with a maginfying glass, = and there was no dark or black area around the break, as there often = appears after a fuse blows. What we did notice, however is that the gage = of the wire inside the fuse looked suspiciously small. We compared it to = 5 or 6 other 20 amp fuses we had, and the wire was definately smaller in = gage. It looked to be the same size as a 7 1/2 amp fuse we compared it = to. It did, however have the standard yellow plastic cap and marking of = 20 on it. It definately was a lighter gage wire used for the fuse = portion than the other 20 amp fuses we had. Possibly a manufacturing = defect, or maybe it was a 7 1/2 amp fuse and it received a yellow cap = marked 20 amps somewhere along the assembly line or ??? Don't know the = answer to this one, but there is no doubt at all that the wire was = similar in size to a 7 1/2 amp fuse. Maybe something to look at when = installing them. Might have been made on a Monday or a Friday. FWIW. = Paul Conner ----- Original Message -----=20 From: Ed Anderson=20 To: Rotary motors in aircraft=20 Sent: Monday, May 02, 2005 8:16 AM Subject: [FlyRotary] To Fuse or not to Fuse=20 Since this is the umpteenth time that the fuse vs CB topic has come = up (not just on the rotary lists but aircraft list in general), and = certainly won't e the last, I decided to do something different than = just spout my views on the topic. I surfed the net and see if I could = find anything on it. Here are some of the URLs I found of interest. This guy actually did some tests and found among other things that a = fuse rated capacity can slowly degrade with repeated high current flows = even if below its burst point. But, read it and draw your own = conclusions. = http://www.campbells.org/Airplanes/AirplaneCircuitBreakersVsFuses.html This one has an interesting summary, but since they are presented by = the makers of CB can be considered Biased http://www.adverc.co.uk/technical/technical-fuses.asp Another maker of CB propaganda, however they do point out that you = can not test a fuse since it is destroyed if it proves it works at the = specified rating where as you can a CB = http://www.ammagazine.com/CDA/ArticleInformation/features/BNP__Features__= Item/0,2606,111238,00.html Here is Bob K's and his well reasoned argument FOR fuses http://www.aeroelectric.com/articles/Rev9/ch10-9.pdf It appears that there is as much debate outside the aviation = community (or more) about fuses Vs CB. It appears to me the CB is = winning there simply because of convince rather than any technical = advantage - That is once the problem causing the short is fixed, you = simply reset the CB rather than trying to find a fuse of the right = rating and shape to replace the blown one and possibly sticking in the = wrong fuse. And you know Americans - convince before all else {:>) - At = least that's the way it appears to me. Ed Ed Anderson Rv-6A N494BW Rotary Powered Matthews, NC eanderson@carolina.rr.com -------------------------------------------------------------------------= --- No virus found in this incoming message. Checked by AVG Anti-Virus. Version: 7.0.308 / Virus Database: 266.11.1 - Release Date: 5/2/2005 ------=_NextPart_000_0015_01C55148.55CC6180 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Hi Paul,
 
You loose nothing by having a reset = possibility -=20 something you do not have with a fuse.  Those of use who have = successfully=20 reset a CB and regained a system just have a hard time understanding why = anyone=20 would want to forego the possibility of being able to regain a critical=20 system.  True, it may not work every time or even most times, but = its=20 worked enough times for me and others (such as yourself) to make it a = viable=20 choice.  Like I say I use fuses - just not on flight critical=20 systems. 
 
However, for those who decide to use = fuses, I think=20 your discovery of apparently a apparently mismatched fuse should be = something they add to their check list when installing/replacing=20 fuses. I suppose if you use a different metal as the fuse = link (I=20 don't have any ideal which alloy is used) then you might could use = a=20 thinner link - but I would think the alloy would be pretty = standard.  =20 But, Like you said could have been made in China on a Monday or = Friday or=20 someone hired a color-vision impaired person to put the caps=20 on{:>).   Good detective work!
 
Ed
----- Original Message -----
From:=20 Paul=20
Sent: Thursday, May 05, 2005 = 12:29=20 AM
Subject: [FlyRotary] Re: To = Fuse or not=20 to Fuse

Hi, Ed....thanks for the links.  = After=20 successfully resetting fuses in military aircraft, I feel more comfort = in=20 knowing that I at least have the option to reset or not to = reset.  In one=20 case, it was the landing gear motor on a King Air that got pretty hot = during=20 touch-and-go's during a checkride. Once the motor cooled, the circuit = breaker=20 was successfully reset, and we were able to lower the gear. I am = replacing my=20 fuel pump fuses with CB's.
     Anyway, the = purpose of=20 this email is to comment on the fuse that blew on my fuel pump = circuit. We=20 looked at it with a maginfying glass, and there was no dark or black = area=20 around the break, as there often appears after a fuse blows. What we = did=20 notice, however is that the gage of the wire inside the fuse looked=20 suspiciously small. We compared it to 5 or 6 other 20 amp fuses we = had, and=20 the wire was definately smaller in gage. It looked to be the same size = as a 7=20 1/2 amp fuse we compared it to. It did, however have the standard = yellow=20 plastic cap and marking of 20 on it.  It definately was a lighter = gage=20 wire used for the fuse portion than the other 20 amp fuses we had. = Possibly a=20 manufacturing defect, or maybe it was a 7 1/2 amp fuse and it received = a=20 yellow cap marked 20 amps somewhere along the assembly line or = ???  Don't=20 know the answer to this one, but there is no doubt at all that the = wire was=20 similar in size to a 7 1/2 amp fuse. Maybe something to look at when=20 installing them. Might have been made on a Monday or a = Friday.  =20 FWIW.   Paul Conner
 
----- Original Message -----
From:=20 Ed Anderson
To: Rotary motors in = aircraft=20
Sent: Monday, May 02, 2005 = 8:16=20 AM
Subject: [FlyRotary] To Fuse = or not to=20 Fuse

 
Since this is the umpteenth time = that the fuse=20 vs CB topic has come up (not just on the rotary lists but aircraft = list in=20 general), and certainly won't e the last, I decided to do something=20 different than just spout my views on the topic.  I surfed the = net and=20 see if I could find anything on it.
 
Here are some of the URLs I found = of=20 interest.
 
This guy actually did some tests = and found=20 among other things that a fuse rated capacity can slowly degrade = with=20 repeated high current flows even if below its burst point.  = But, read=20 it and draw your own conclusions.
 
http://www.campbells.org/Airplanes/AirplaneCircuitBreakersVsFuses.= html
 
This one has an interesting = summary, but since=20 they are presented by the makers of CB can be considered = Biased
 
http://www= .adverc.co.uk/technical/technical-fuses.asp
 
 
Another maker of CB propaganda, = however they do=20 point out that you can not test a fuse since it is destroyed if it = proves it=20 works at the specified rating where as you can a CB
 
http://www.ammagazine.com/CDA/Article= Information/features/BNP__Features__Item/0,2606,111238,00.html=
 
Here is Bob K's and his well = reasoned =20 argument  FOR fuses
 
http://www.= aeroelectric.com/articles/Rev9/ch10-9.pdf
 
 
It appears that there is as much = debate outside=20 the aviation community (or more) about fuses Vs CB.  It appears = to me=20 the CB is winning there simply because of convince rather than any = technical=20 advantage -  That is once the problem causing the short is = fixed, you=20 simply reset the CB rather than trying to find a fuse of the right = rating=20 and shape to replace the blown one and possibly sticking in the = wrong=20 fuse. And you know Americans - convince before all else {:>) = -=20  At least that's the way it appears to me.
 
Ed
 
Ed Anderson
Rv-6A N494BW Rotary=20 Powered
Matthews, NC
eanderson@carolina.rr.com

No virus found in this incoming message.
Checked by AVG=20 Anti-Virus.
Version: 7.0.308 / Virus Database: 266.11.1 - Release = Date:=20 5/2/2005
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