---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Fri 02/24/23: 2 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:48 AM - Re: Re: fuses in series (Robert L. Nuckolls, III) 2. 06:01 AM - Re: Re: fuses in series (Matthew Whiting) ________________________________ Message 1 _____________________________________ Time: 05:48:14 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: fuses in series At 09:18 PM 2/23/2023, you wrote: > >Theories need to be proven by experimenting and testing. >Dan's testing shows that it is OK to have fuses in series. >On the other hand, why take a chance on the main fuse blowing when >there are are alternatives? What FMEA conditions ever suggest that fuses in series are a good and necessary thing? I've read several narratives where the writer talks about a "main" breaker . . . and I cannot imagine what they're talking about or just how such a device became a part of his/her airplane. Bob . . . Un impeachable logic: George Carlin asked, "If black boxes survive crashes, why don't they make the whole airplane out of that stuff?" ________________________________ Message 2 _____________________________________ Time: 06:01:15 AM PST US From: Matthew Whiting Subject: Re: AeroElectric-List: Re: fuses in series I could see someone following the architecture used in home and building electrical distribution systems where series fuses/breakers are very common. Electric utilities have fuses on their distribution lines. Most buildings have a main breaker on the incoming service. And then each circuit has a breaker. And finally many end devices have their own internal fuses or breakers. So, fuses/breakers in series are common in many applications. I don=99t recall seeing that in a vehicle though, although I think my new Equinox does have a fuse on the main positive battery lead, which is a first. Why would one not want to have a fuse on the main battery lead to protect a short of the battery cable? I know this isn=99t common, but I also have seen battery cables contact ground a few times and the results are generally fairly impressive. Is the issue just one of not wanting an additional point of failure? Or the cost of a large fuse and fuse holder? Regards, Matt > On Feb 24, 2023, at 8:47 AM, Robert L. Nuckolls, III wrote: > > At 09:18 PM 2/23/2023, you wrote: >> >> Theories need to be proven by experimenting and testing. >> Dan's testing shows that it is OK to have fuses in series. >> On the other hand, why take a chance on the main fuse blowing when there are are alternatives? > > > What FMEA conditions ever suggest that fuses > in series are a good and necessary thing? > > I've read several narratives where the writer > talks about a "main" breaker . . . and I cannot > imagine what they're talking about or just how > such a device became a part of his/her > airplane. > > > Bob . . . > > Un impeachable logic: George Carlin asked, "If black boxes > survive crashes, why don't they make the whole airplane > out of that stuff?" > ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message aeroelectric-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/AeroElectric-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/aeroelectric-list Browse Digests http://www.matronics.com/digest/aeroelectric-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.