X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail-px0-f190.google.com ([209.85.216.190] verified) by logan.com (CommuniGate Pro SMTP 5.2.14) with ESMTP id 3672956 for flyrotary@lancaironline.net; Fri, 05 Jun 2009 13:04:07 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.216.190; envelope-from=wdleonard@gmail.com Received: by pxi28 with SMTP id 28so214221pxi.7 for ; Fri, 05 Jun 2009 10:03:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:in-reply-to:references :date:message-id:subject:from:to:content-type; bh=1AsxHCvmYfnV9BR2NuUaYgMr+YyZLB3wpZ4YqkQbsC8=; b=mFWA2M2aoARMxgTbEHEakRTO/QZx4dN/D0oLCKaWWdS/U87wQeeV5cTO3n7XlfJuIN uoXOdPTkqSla9xRtBIGDmznZWquWRM2q2zcZyyLAFpve0aAiwNGV16l0yQtrpAeHrMzZ O8ZMDj5SpNmnsmc4MWXJGzvDNRirfj/o2pA0M= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; b=hrXePPGUljgoYKlx2O8546esC5tTK6nFASrfkpFqRtqhMNS8AM+vpPB9XcPm6xpBwq K1IZTdtfQhy3KCXcpPsYM63csy/oPzdFrbuHSj/OyFmAQlJrr9V40zPd/muDOL3Tfbsp P+y8OJOeq/XdvUxeX0i7u95i37iTUbxNpR8b8= MIME-Version: 1.0 Received: by 10.220.73.209 with SMTP id r17mr2627576vcj.46.1244221408326; Fri, 05 Jun 2009 10:03:28 -0700 (PDT) In-Reply-To: References: Date: Fri, 5 Jun 2009 10:03:28 -0700 Message-ID: <1c23473f0906051003i1999c425t1134c50a0cdb5428@mail.gmail.com> Subject: Re: [FlyRotary] Ed's Electrical System was Incident 5119 From: David Leonard To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary=00163631086710b6fb046b9cdfb4 --00163631086710b6fb046b9cdfb4 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Hi Ed, Great job handling the emergency! Very nice write up. I do have to admit that you made some unusual decisions in the electrical system. None of that stuff is new, electric Bob's advice is pretty sound. I think that the "master" solenoid is often called the "battery" master for a reason - it only isolates the battery. If you want to have another battery, have another battery master that truly isolates that battery. In your system, if either battery becomes a dead short - you have just taken out your essential buss with no way to recover in flight! All your buses (essential or not) should be on the other side of the 'master' solenoids. If you want to be able to isolate the alternator, that is a separate system. (crow-bar/solenoid/field switch/fuse link/breaker/whatever). I have come to the opinion that sudden over-voltage that frys your avionics is exceedingly unlikely. I have decided to only "isolate" my alternator with a fusible link. - nice and simple that way. The alternator also connects to the buss side of the battery master solenoids. To make one of the buses 'essential' provide an alternate path around any perceived possible points of failure. Batteries fail. I have seen it in cars, I'm sure you have too. Sure, it's mostly the older type, but a good solid short across a SLA could fail it as well. I also find it unusual that your voltmeter is not simply reading the main buss voltage - no fancy switch. That way, you know what you are getting, if you know what I mean. If you want to see how one or another power source is doing, isolate the other sources from the master buss. Lastly, what about you ammeter? Does it not measure current directly from either the battery or the alternator? I'm not sure that a diode is the solution you are looking for. I think what you really need is to re-do the big wires in your system altogether. If you have settled on a one-battery system, get rid of all that extra weight and do it according to the book. From what I know, you would use a diode to 1) re-route field decay spikes back to the battery, or 2) provide alternate path from a battery to an essential (always hot) buss. (i.e. If you wanted to use a diodes, your essential buss would be connected to the other side of the master contactors via diodes, and you would use a diode from each battery to the essential buss.) So at a minimum you would want 2 diodes, one from the alternator and another from your single battery to the essential buss. I know you are a WAY better gEEk than me (i cant even spell AC). So I suspect that you already know what I am saying and you just need a kick in the arse to bite the bullet and re-do the system. Highest regards as always, -- David Leonard Turbo Rotary RV-6 N4VY http://N4VY.RotaryRoster.net http://RotaryRoster.net On Fri, Jun 5, 2009 at 4:47 AM, Ed Anderson wrote: > > > Jim Maher was kind enough to convert the large DXF files of my electrical > system to JPG so perhaps more of you can examine it. Recall I have removed > the 2nd battery stuff - so ignore that on the diagrams. Also the diagram > does not show any of the detailed EC2/injector/ignition wiring - follow > Tracy's recommendations on that. > > As you will note there is no "isolation" diode between alternator and > battery and also that the battery voltage holds the master relay closed. > That is another change I must make. I must have decided (10+ years ago) > that the battery would never fail - only the alternator. Clearly (now), > without battery voltage (in my design) to hold the master relay closed - > when the battery voltage fall to around 6-7 volts (in my case) the relay > opens and all that good electrical power being produced by the perfectly > good alternator - can not reach any part of the electrical system. Clearly > NOT good as I could have continued to fly perfectly well with just the > alternator juice. > > Your design is not going to be any better than the accuracy of your > assumptions. Clearly some of my assumptions make 10 years ago definitely > need revising. > > Ed > > > The message is ready to be sent with the following file or link > attachments: > > DIAG_3B.jpg > DIAG_2B.jpg > DIAG_1B.jpg > > > Note: To protect against computer viruses, e-mail programs may prevent > sending or receiving certain types of file attachments. Check your e-mail > security settings to determine how attachments are handled. > > > __________ Information from ESET NOD32 Antivirus, version of virus > signature > database 3267 (20080714) __________ > > The message was checked by ESET NOD32 Antivirus. > > > > -- > Homepage: http://www.flyrotary.com/ > Archive and UnSub: > http://mail.lancaironline.net:81/lists/flyrotary/List.html > > --00163631086710b6fb046b9cdfb4 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable
Hi Ed,
=A0
Great job handling the emergency!=A0 Very nice write up.=A0=A0 I do ha= ve to admit that you made some unusual decisions in the electrical system.= =A0 None of that stuff is new, electric Bob's advice is pretty sound.= =A0 I think that the "master" solenoid is often called the "= battery" master for a reason - it only isolates the battery.=A0 If you= want to have another battery, have another battery master that truly isola= tes that battery.=A0 In your system, if either battery becomes a dead short= - you have just taken out your essential buss with no way to recover in fl= ight!=A0 All your buses (essential or not) should be=A0on the other side of= the=A0'master' solenoids.=A0=A0=A0 If you want to be able to isola= te the alternator, that is a separate system. (crow-bar/solenoid/field swit= ch/fuse link/breaker/whatever).=A0 I have come to the opinion that sudden o= ver-voltage that frys your avionics is exceedingly unlikely.=A0 I have deci= ded to only "isolate" my=A0alternator with a fusible link. - nice= and simple that way.=A0 The alternator also connects to the buss side of t= he battery master solenoids.=A0 To make one of the buses=A0'essential&#= 39; provide an alternate path around any perceived possible points of failu= re. Batteries fail.=A0 I have seen it in cars, I'm sure you have too.= =A0 Sure, it's mostly the older type, but a good solid short across a S= LA could fail it as well.
=A0
I also find it unusual that your voltmeter is not simply reading the m= ain buss voltage - no fancy switch.=A0 That way, you know what you are gett= ing, if you know what I mean.=A0 If you want to see=A0how one or another=A0= power source is doing, isolate the other sources from the=A0master buss.=A0= =A0=A0 Lastly, what about you ammeter?=A0 Does it not measure current direc= tly=A0from either the battery or the alternator?=A0=A0
=A0
I'm not sure that a diode is the solution you are looking for.=A0= =A0 I think what you really need is to re-do the big wires in your system a= ltogether.=A0 If you have settled on a one-battery system, get rid of all t= hat extra weight and do it according to the book.=A0 From what I know, you = would use a diode to 1) re-route field decay spikes back to the battery, or= =A02) provide alternate path from a battery to an essential (always hot)=A0= buss.=A0 (i.e. If you wanted to use a diodes, your essential buss would be = connected to the other side of the master contactors via diodes, and you wo= uld use a diode from each battery to the essential buss.)=A0 So at a minimu= m you would want 2 diodes, one from the alternator and another from your si= ngle battery to the essential buss.
=A0
I know you are a WAY better gEEk than me (i cant even spell AC).=A0 So= I suspect that you already know what I am saying and you just need a kick = in the arse to bite the bullet and re-do the system.=A0
=A0
Highest regards as always,
=A0
--
David Leonard

Turbo Rotary RV-6 N4VY
http://N4VY.RotaryRoster.net
http://RotaryRo= ster.net


On Fri, Jun 5, 2009 at 4:47 AM, Ed Anderson <eanderson@carolina.rr.com> wrote:


Jim Maher was kind enoug= h to convert the large DXF files of my electrical
system to JPG so perha= ps more of you can examine it. =A0Recall I have removed
the 2nd battery stuff - so ignore that on the diagrams. =A0Also the diagram=
does not show any of the detailed EC2/injector/ignition wiring - follow=
Tracy's recommendations on that.

As you will note there is n= o "isolation" diode between alternator and
battery and also that the battery voltage holds the master relay closed.That is another change I must make. =A0I must have decided (10+ years ago)=
that the battery would never fail - only the alternator. =A0Clearly (no= w),
without battery voltage (in my design) to hold the master relay =A0closed -=
when the battery voltage fall to around 6-7 volts (in my case) the rela= y
opens and all that good electrical power being produced by the perfect= ly
good alternator - can not reach any part of the electrical system. =A0Clear= ly
NOT good as I could have continued to fly perfectly well with just th= e
alternator juice.

Your design is not going to be any better tha= n the accuracy of your
assumptions. =A0Clearly some of my assumptions make 10 years ago definitely=
need revising.

Ed


The message is ready to be sent wit= h the following file or link attachments:

DIAG_3B.jpg
DIAG_2B.jpg=
DIAG_1B.jpg


Note: To protect against computer viruses, e-mail pr= ograms may prevent
sending or receiving certain types of file attachment= s. =A0Check your e-mail
security settings to determine how attachments a= re handled.


__________ Information from ESET NOD32 Antivirus, version of virus = signature
database 3267 (20080714) __________

The message was che= cked by ESET NOD32 Antivirus.



--
Homepage: =A0http://www.flyrotary.com/<= br> Archive and UnSub: =A0 http://mail.lancaironline.net:81/lists= /flyrotary/List.html




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