X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from fmailhost06.isp.att.net ([207.115.11.56] verified) by logan.com (CommuniGate Pro SMTP 5.2.14) with ESMTP id 3745595 for flyrotary@lancaironline.net; Sun, 05 Jul 2009 13:08:25 -0400 Received-SPF: none receiver=logan.com; client-ip=207.115.11.56; envelope-from=keltro@att.net DKIM-Signature: v=1; q=dns/txt; d=att.net; s=dkim01; i=keltro@att.net; a=rsa-sha256; c=relaxed/relaxed; t=1246813707; h=Content-Type: MIME-Version:In-Reply-To:Message-Id:Date:Subject:To:From; bh=PzYTZH KXNvOIYfxOQDyim0T0mtlmt3f93YSpekM5zQc=; b=YOFFCz88rrEkZaClgW8+x/B8r 6n58EDlwEKrFaYsIsVw5B1C5TMrqMOnDGSmSxG0FmaPGtQ75DASNii6VwrljA== Received: from fwebmail16.isp.att.net ([207.115.9.156]) by isp.att.net (frfwmhc06) with SMTP id <20090705170750H0600i20boe>; Sun, 5 Jul 2009 17:07:51 +0000 X-Originating-IP: [207.115.9.156] Received: from [64.250.203.232] by fwebmail16.isp.att.net; Sun, 05 Jul 2009 17:07:50 +0000 From: "Kelly Troyer" To: "Rotary motors in aircraft" Subject: Re: Modify Alternator for External Regulator Date: Sun, 05 Jul 2009 17:07:50 +0000 Message-Id: <070520091707.7541.4A50DDE6000758F400001D7522218801869B0A02D29B9B0EBF019D9B040A05@att.net> In-Reply-To: X-Mailer: AT&T Message Center Version 1 (Mar 2 2009) X-Authenticated-Sender: a2VsdHJvQGF0dC5uZXQ= MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="NextPart_Webmail_9m3u9jl4l_7541_1246813670_0" --NextPart_Webmail_9m3u9jl4l_7541_1246813670_0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Group, I appreciate all the different opinions and perspectives about this sub= ject............Each of us as experimenters has to decide for themselves their comfortable risk level....= .......I currently have a Mazda alternator modified as described on my Chevrolet V6 powered 1988 RX7 = with about 60,000 miles on the conversion (My 13B lost compression and I f= eel Rotarys are wasted in cars so will now power my Dyke Delta)...............The internal = regulator failed but=20 failed open instead of an internal short which would have allowed runaway v= oltage.........I do realize that the majority of failures fail open , "But" my personal risk le= vel still wanted the ability to switch off field voltage and shut the alternator down in my "Delta".....= ......I do not currently have a switch in the field circuit of my RX7 but will be installing one to = test this as there has=20 been some discussion that residual magnetism in the fields might prevent th= e alternator from shuting down............Will report my findings........... I realize that abilities among experimental aircraft builders vary bu= t in my opinion if you can build a safe and flyable aircraft with a Mazda Rotary engine then the s= kills needed to modify a Mazda alternator should be no problem...........This is not rocket= science , all you are doing is removing an internal regulator (I think the entire circuitry s= hould be removed as=20 I previously stated) the brushes connected to ground and the field windings= connected to a now unused external connector..........Until the advent of the internal r= egulator alternators were all built this way electrically.............IMHO & FWIW -- Kelly Troyer=20 "Dyke Delta"_13B ROTARY Engine=20 "RWS"_RD1C/EC2/EM2=20 "Mistral"_Backplate/Oil Manifold=20 -------------- Original message from "Mike Wills" : -----= ---------=20 > Charlie,=20 >=20 > Thanks for this perspective on the risk/benefit ratio of this particular= =20 > mod. I too fly with an unmodified 1 wire alternator. Or at least I would = if=20 > I were currently flying.=20 >=20 > Our airplanes are complicated enough what with EFI, EI, microprocessors,= =20 > etc., without adding to the complexity (and potential failure modes) by= =20 > adding "protection" to guard against 1 in a million failures. At least th= ats=20 > my perspective.=20 >=20 > Mike Wills=20 > RV-4 N144MW=20 >=20 > ----- Original Message -----=20 > From: "Charlie England"=20 > Subject: [FlyRotary] Re: Overvoltage ? [FlyRotary] Re: Modify Alternator = for=20 > External Regulator=20 >=20 > > If you have a controllable circuit breaker or a switchable relay in ser= ies=20 > > with the B-lead, you can control an over-voltage event. The Aeroelectri= c=20 > > connection offered a 'crowbar' type protector for a while that would=20 > > disconnect the B-lead automatically, and if memory serves, Bob Nuckolls= =20 > > now says that with an effective attention-getter to notify of=20 > > over-voltage, the battery will easily damp the voltage to below=20 > > damage-causing levels long enough to hit the B-lead disconnect. The onl= y=20 > > issue left is whether there is enough combustible material in the=20 > > alternator itself to cause any real danger as it runs away, electricall= y=20 > > isolated from the rest of the plane.=20 > >=20 > > My personal opinion is that each person should carefully evaluate the= =20 > > relative risks of opening & modifying an inherently extremely reliable= =20 > > device, at their personal skill level. I spent about half my working li= fe=20 > > doing electronics service work and I'm pretty confident in my abilities= in=20 > > this area. My flying RV-4 (Lyc) has an unmodified '1-wire' alternator.= =20 > >=20 > > Charlie=20 > >=20 > > Ed Anderson wrote:=20 > >>=20 > >> Just curious, Todd. When you had your alternator run-a-way, did you ha= ve=20 > >> a battery or other load on the line. Yes and you are correct, just=20 > >> because the odds are 1 in 1000,000 does not mean your 1 couldn=E2=80= =99t come up=20 > >> tomorrow. And I STILL DON=E2=80=9DT use approved plastic fuel cans (or= any other=20 > >> kind) =E2=80=93 one refueling fire was enough {:>).=20 > >>=20 > >> Thanks for providing that info to the list =E2=80=93 now others can se= e=20 > >> alternator over voltage is a possibility with a car alternator and=20 > >> without the modification to the field coil circuit may be impossible t= o=20 > >> shut down =E2=80=93 short of shutting down your engine.=20 > >>=20 > >> But, if 60 years of experience is not worth anything regarding=20 > >> alternators =E2=80=93 then what is experience worth regarding anything= . Like just=20 > >> about everything else in this =E2=80=9Chobby=E2=80=9D, you are constan= tly assessing risk=20 > >> (or should be) and I decided the risk of modifying my alternator to=20 > >> eliminate the remote risk (base on my experience) of over voltage was= =20 > >> higher than an over voltage condition. YMMV {:>)=20 > >>=20 > >> Ed.=20 > >> *On Behalf Of *Todd Bartrim=20 > >> *Sent:* Sunday, July 05, 2009 3:07 AM=20 > >> *Subject:* [FlyRotary] Re: Modify Alternator for External Regulator=20 > >>=20 > >> Yeah, that's what I said too Ed, then it happened to me when I was sti= ll=20 > >> early in my flight test (on the ground fortunatly).=20 > >> However after years of carelessly pouring regular old auto fuel from= =20 > >> plastic fuel cans, despite all the warnings, I've yet to have a proble= m.=20 > >> But I did hear of a guy that caught his plane on fire this way. ;)=20 > >> So yeah, I'm sure it could happen. Hope it doesn't though. It would su= re=20 > >> ruin my day.=20 > >>=20 > >> Could it happen, undoubtedly, however, in 60 + years of driving=20 > >> automobiles, I have never, never had an alternator run wild =E2=80=93 = the ones=20 > >> that failed, just died. So if I can get by another 60 years {:>), then= I=E2=80=99ll=20 > >> probably hang up my wings (or who knows perhaps get another pair {:>)= =20 > >>=20 > >> Ed=20 --NextPart_Webmail_9m3u9jl4l_7541_1246813670_0 Content-Type: multipart/related; boundary="NextPart_Webmail_9m3u9jl4l_7541_1246813670_1" --NextPart_Webmail_9m3u9jl4l_7541_1246813670_1 Content-Type: text/html; charset="utf-8" Content-Transfer-Encoding: quoted-printable
 
Group,
 
    I appreciate all the different opinions and perspec= tives about this subject............Each of us as
experimenters has to decide for themselves their comfortable risk leve= l...........I currently have a
Mazda alternator modified as described on my Chevrolet V6 powered 1988= RX7 with about
60,000 miles on the conversion (My 13B lost compression <apex seal&= gt; and I feel Rotarys are
wasted in cars so will now power my Dyke Delta)...............The inte= rnal regulator failed but
failed open instead of an internal short which would have allowed runa= way voltage.........I do
realize that the majority of failures fail open , "But" my personal ri= sk level still wanted the ability
to switch off field voltage and shut the alternator down in my "Delta"= ...........I do not currently
have a switch in the field circuit of my RX7 but will be installing on= e to test this as there has
been some discussion that residual magnetism in the fields might preve= nt the alternator from
shuting down............Will report my findings...........
 
      I realize that abilities among experime= ntal aircraft builders vary but in my opinion if you
can build a safe and flyable aircraft with a Mazda Rotary en= gine then the skills needed to
modify a Mazda alternator should be no problem...........This is not r= ocket science , all you
are doing is removing an internal regulator (I think the entire c= ircuitry should be removed as
I previously stated) the brushes connected to ground and the field win= dings connected to
a now unused external connector..........Until the advent of the inter= nal regulator alternators
were all built this way electrically.............IMHO & FWIW
--
Kelly Troyer
"Dyke Delta"_1= 3B ROTARY Engine
"RWS"_RD1C/EC2/EM2
"Mistral"_Backplate/Oil Manifol= d
-------------- Original message from "Mike Wills" <rv-4mi= ke@cox.net>: --------------

> Charlie,
>
> Than= ks for this perspective on the risk/benefit ratio of this particular
&g= t; mod. I too fly with an unmodified 1 wire alternator. Or at least I would= if
> I were currently flying.
>
> Our airplanes are c= omplicated enough what with EFI, EI, microprocessors,
> etc., withou= t adding to the complexity (and potential failure modes) by
> adding= "protection" to guard against 1 in a million failures. At least thats
= > my perspective.
>
> Mike Wills
> RV-4 N144MW
= >
> ----- Original Message -----
> From: "Charlie England"=
> Subject: [FlyRotary] Re: Overvoltage ? [= FlyRotary] Re: Modify Alternator for
> External Regulator
> <= BR>> > If you have a controllable circuit breaker or a switchable rel= ay in series
> > with the B-lead, you can control an over-voltage= event. The Aeroelectric
> > connection offered a 'crowbar' type = protector for a while that would
> > disconnect the B-lead automa= tically, and if memory serves, Bob Nuckolls
> > now says that wit= h an effective attention-getter to notify of
> > over-voltage, th= e battery will easily damp the voltage to below
> > damage-causin= g levels long enough to hit the B-lead disconnect. The only
> > i= ssue left is whether there is enough combustible material in the
> &= gt; alternator itself to cause any real danger as it runs away, electricall= y
> > isolated from the rest of the plane.
> >
>= > My personal opinion is that each person should carefully evaluate the=
> > relative risks of opening & modifying an inherently extr= emely reliable
> > device, at their personal skill level. I spent= about half my working life
> > doing electronics service work an= d I'm pretty confident in my abilities in
> > this area. My flyin= g RV-4 (Lyc) has an unmodified '1-wire' alternator.
> >
> = > Charlie
> >
> > Ed Anderson wrote:
> >&g= t;
> >> Just curious, Todd. When you had your alternator run-a= -way, did you have
> >> a battery or other load on the line. Y= es and you are correct, just
> >> because the odds are 1 in 10= 00,000 does not mean your 1 couldn=E2=80=99t come up
> >> tomo= rrow. And I STILL DON=E2=80=9DT use approved plastic fuel cans (or any othe= r
> >> kind) =E2=80=93 one refueling fire was enough {:>). =
> >>
> >> Thanks for providing that info to the l= ist =E2=80=93 now others can see
> >> alternator over voltage = is a possibility with a car alternator and
> >> without the mo= dification to=20the field coil circuit may be impossible to
> >&g= t; shut down =E2=80=93 short of shutting down your engine.
> >>= ;
> >> But, if 60 years of experience is not worth anything re= garding
> >> alternators =E2=80=93 then what is experience wor= th regarding anything. Like just
> >> about everything else in= this =E2=80=9Chobby=E2=80=9D, you are constantly assessing risk
> &= gt;> (or should be) and I decided the risk of modifying my alternator to=
> >> eliminate the remote risk (base on my experience) of ove= r voltage was
> >> higher than an over voltage condition. YMMV= {:>)
> >>
> >> Ed.
> >> *On Beha= lf Of *Todd Bartrim
> >> *Sent:* Sunday, July 05, 2009 3:07 AM=
> >> *Subject:* [FlyRotary] Re: Modify Alternator for Externa= l Regulator
> >>
> >> Yeah, that's what I said to= o Ed, then it happened to me when I was still
> >> early in my= flight test (on the ground fortunatly).
> >> However after ye= ars of carelessly pouring regular old auto fuel from
> >> plas= tic fuel cans, despite all the warnings, I've yet to have a problem.
&g= t; >> But I did hear of a guy that caught his plane on fire this way.= ;)
> >> So yeah, I'm sure it could happen. Hope it doesn't th= ough. It would sure
> >> ruin my day.
> >>
&g= t; >> Could it happen, undoubtedly, however, in 60 + years of driving=
> >> automobiles, I have never, never had an alternator run w= ild =E2=80=93 the ones
> >> that failed, just died. So if I ca= n get by another 60 years {:>), then I=E2=80=99ll
> >> prob= ably hang up my wings (or who knows perhaps get another pair {:>)
&g= t; >>
> >> Ed
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