---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Thu 05/04/17: 7 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 10:39 AM - Re: Overvoltage event (non-lithium battery) (Robert L. Nuckolls, III) 2. 11:14 AM - Re: Overvoltage event (non-lithium battery) (John Tipton) 3. 01:14 PM - Re: Overvoltage event (non-lithium battery) (Robert L. Nuckolls, III) 4. 02:27 PM - Re: Overvoltage event (non-lithium battery) (Bernie) 5. 05:37 PM - Re: Overvoltage event (non-lithium battery) (Robert L. Nuckolls, III) 6. 06:40 PM - Re: Overvoltage event (non-lithium battery) (Neil Rosoff) 7. 06:52 PM - Re: Overvoltage event (non-lithium battery) (Bernie) ________________________________ Message 1 _____________________________________ Time: 10:39:06 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Overvoltage event (non-lithium battery) At 07:47 PM 5/3/2017, you wrote: >This may be a naive question but is there any reason why then I >can't use one master switch to turn on both the battery and alternator? >If I turn my master off and e-bus on I would then be on battery-only >operation. That's fine . . . in fact, that configuration is illustrated in Z-13/8 http://tinyurl.com/kgg8nva Emacs! This configuration exploits the fact that crowbar ovm systems are typically installed with the popular miniature pullable breakers. This means that when you want to do battery-only ground operations for maintenance, you can pull the alternator field breaker and REMOVE a significant (2.5 to 3 amp) drain on the battery by the field circuit of a non-rotating alternator. But if you system is all fuses or non-pullable breaker, then the progressive transfer switching of battery/alternator (al la legacy split rocker switches), is recommended. Bob . . . ________________________________ Message 2 _____________________________________ Time: 11:14:52 AM PST US Subject: Re: AeroElectric-List: Overvoltage event (non-lithium battery) From: John Tipton So: those aircraft which have an array of switches together either their arr ay of CB's only really need the CB's John Sent from my iPad ----x--O--x---- > On 4 May 2017, at 06:37 pm, "Robert L. Nuckolls, III" wrote: > > At 07:47 PM 5/3/2017, you wrote: >> This may be a naive question but is there any reason why then I can't use one master switch to turn on both the battery and alternator? >> If I turn my master off and e-bus on I would then be on battery-only oper ation. > > That's fine . . . in fact, that configuration > is illustrated in Z-13/8 > > http://tinyurl.com/kgg8nva > > > > <10578c0e.jpg> > > This configuration exploits the fact that > crowbar ovm systems are typically installed > with the popular miniature pullable breakers. > > This means that when you want to do battery-only > ground operations for maintenance, you can pull > the alternator field breaker and REMOVE a > significant (2.5 to 3 amp) drain on the > battery by the field circuit of a non-rotating > alternator. > > But if you system is all fuses or non-pullable > breaker, then the progressive transfer switching > of battery/alternator (al la legacy split rocker > switches), is recommended. > > Bob . . . ________________________________ Message 3 _____________________________________ Time: 01:14:37 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Overvoltage event (non-lithium battery) At 01:13 PM 5/4/2017, you wrote: >So: those aircraft which have an array of switches together either >their array of CB's only really need the CB's > >John No . . . breakers and/or fuses are not operational devices . . . only protective with the occasional instance of being a useful maintenance adjunct. Lots of aircraft maintenance procedures will call for disabling a system by opening the circuit protection . . . but the pilot's operating handbook will (or at least should) never call for routinely operating a breaker as part of normal operations. Circuit protection clusters at the power distribution bus(ses) grouped according to power distribution design goals. On the other hand, switches may be organized for operational functionality irrespective of the power source. Emacs! Bob . . . ________________________________ Message 4 _____________________________________ Time: 02:27:13 PM PST US From: Bernie Subject: Re: AeroElectric-List: Overvoltage event (non-lithium battery) Some builders in an effort to reduce weight use circuit breaker switches ins tead of separate breakers and switches. Is this a bad idea? Bernie Sent from my iPhone > On May 4, 2017, at 12:13 PM, Robert L. Nuckolls, III wrote: > > At 01:13 PM 5/4/2017, you wrote: >> So: those aircraft which have an array of switches together either their a rray of CB's only really need the CB's >> >> John > > No . . . breakers and/or fuses are not operational > devices . . . only protective with the occasional instance > of being a useful maintenance adjunct. > > Lots of aircraft maintenance procedures will call > for disabling a system by opening the circuit > protection . . . but the pilot's operating handbook > will (or at least should) never call for routinely > operating a breaker as part of normal operations. > > Circuit protection clusters at the power distribution > bus(ses) grouped according to power distribution > design goals. > > On the other hand, switches may be organized for > operational functionality irrespective of the > power source. > > <10e5e47d.jpg> > > > > Bob . . . ________________________________ Message 5 _____________________________________ Time: 05:37:16 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Overvoltage event (non-lithium battery) At 04:25 PM 5/4/2017, you wrote: >Some builders in an effort to reduce weight use circuit breaker >switches instead of separate breakers and switches. Is this a bad idea? >Bernie No . . . those devices are designed for their intended purpose . . . But keep in mind. Breakers/fuses are clustered on power distribution busses. It's nice to save panel space by mounting fuseblocks off the panel . . . out of the way. Once you put a row of breaker-switches on the panel, you've committed to bring a bus=feeder fat-wire to the panel and you have two clusters of circuit protection. Further, you may find that operational grouping of switches is no longer convenient and maybe impossible. We used breaker/switches on the Bonanza/ Baron line . . . never did like those things and they eventually proved to be a pain in the a## "saving weight" by using these things is a poor reason for limiting your design choices in other matters. If it were my airplane, it would be fuse blocks for virtually every protected circuit and plain vanilla toggle switches arranged by ergonomic/operational convenience. Inexpensive, light, low cost of ownership and unimpeded design goals. Bob . . . ________________________________ Message 6 _____________________________________ Time: 06:40:09 PM PST US From: "Neil Rosoff" Subject: RE: AeroElectric-List: Overvoltage event (non-lithium battery) I agree in spirit, BUT I recently ran into an issue where the procedure for handling an ignition system failure indication, is to pull the ignition system breaker while the engine is running. This is not a situation where the manufacture and myself would not want a switch. Neil Rosoff From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Bernie Sent: Thursday, May 4, 2017 5:25 PM Subject: Re: AeroElectric-List: Overvoltage event (non-lithium battery) Some builders in an effort to reduce weight use circuit breaker switches instead of separate breakers and switches. Is this a bad idea? Bernie Sent from my iPhone On May 4, 2017, at 12:13 PM, Robert L. Nuckolls, III wrote: At 01:13 PM 5/4/2017, you wrote: So: those aircraft which have an array of switches together either their array of CB's only really need the CB's John No . . . breakers and/or fuses are not operational devices . . . only protective with the occasional instance of being a useful maintenance adjunct. Lots of aircraft maintenance procedures will call for disabling a system by opening the circuit protection . . . but the pilot's operating handbook will (or at least should) never call for routinely operating a breaker as part of normal operations. Circuit protection clusters at the power distribution bus(ses) grouped according to power distribution design goals. On the other hand, switches may be organized for operational functionality irrespective of the power source. <10e5e47d.jpg> Bob . . . ________________________________ Message 7 _____________________________________ Time: 06:52:06 PM PST US From: Bernie Subject: Re: AeroElectric-List: Overvoltage event (non-lithium battery) Got it! Thanks, Bernie Sent from my iPhone > On May 4, 2017, at 5:36 PM, Neil Rosoff wrote: > > I agree in spirit, BUT I recently ran into an issue where the procedure fo r handling an ignition system failure indication, is to pull the ignition sy stem breaker while the engine is running. This is not a situation where the manufacture and myself would not want a switch. > > Neil Rosoff > > From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelect ric-list-server@matronics.com] On Behalf Of Bernie > Sent: Thursday, May 4, 2017 5:25 PM > To: aeroelectric-list@matronics.com > Subject: Re: AeroElectric-List: Overvoltage event (non-lithium battery) > > Some builders in an effort to reduce weight use circuit breaker switches i nstead of separate breakers and switches. Is this a bad idea? > Bernie > > Sent from my iPhone > > On May 4, 2017, at 12:13 PM, Robert L. Nuckolls, III wrote: > > At 01:13 PM 5/4/2017, you wrote: > > So: those aircraft which have an array of switches together either their a rray of CB's only really need the CB's > > John > > > No . . . breakers and/or fuses are not operational > devices . . . only protective with the occasional instance > of being a useful maintenance adjunct. > > Lots of aircraft maintenance procedures will call > for disabling a system by opening the circuit > protection . . . but the pilot's operating handbook > will (or at least should) never call for routinely > operating a breaker as part of normal operations. > > Circuit protection clusters at the power distribution > bus(ses) grouped according to power distribution > design goals. > > On the other hand, switches may be organized for > operational functionality irrespective of the > power source. > > <10e5e47d.jpg> > > > > > Bob . . . ------------------------------------------------------------------------------------- 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.