X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from imr-mb01.mx.aol.com ([64.12.207.164] verified) by logan.com (CommuniGate Pro SMTP 5.3.9) with ESMTP id 4476745 for flyrotary@lancaironline.net; Wed, 22 Sep 2010 11:52:06 -0400 Received-SPF: pass receiver=logan.com; client-ip=64.12.207.164; envelope-from=Lehanover@aol.com Received: from imo-da04.mx.aol.com (imo-da04.mx.aol.com [205.188.169.202]) by imr-mb01.mx.aol.com (8.14.1/8.14.1) with ESMTP id o8MFpK0h006446 for ; Wed, 22 Sep 2010 11:51:20 -0400 Received: from Lehanover@aol.com by imo-da04.mx.aol.com (mail_out_v42.9.) id q.e8a.70d8af3 (37583) for ; Wed, 22 Sep 2010 11:51:15 -0400 (EDT) Received: from magic-d18.mail.aol.com (magic-d18.mail.aol.com [172.19.155.134]) by cia-mb05.mx.aol.com (v129.4) with ESMTP id MAILCIAMB058-92cf4c9a25f31d5; Wed, 22 Sep 2010 11:51:15 -0400 From: Lehanover@aol.com Message-ID: Date: Wed, 22 Sep 2010 11:51:15 EDT Subject: Re: [FlyRotary] Re: Alternator To: flyrotary@lancaironline.net MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="part1_d033.6e29c804.39cb7ff3_boundary" X-Mailer: 9.0 Security Edition for Windows sub 5381 X-AOL-IP: 173.88.9.178 X-Spam-Flag:NO X-AOL-SENDER: Lehanover@aol.com --part1_d033.6e29c804.39cb7ff3_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 9/22/2010 11:07:43 A.M. Eastern Standard Time, bktrub@aol.com writes: I don't know how likely an overvoltage condition is with the internal regulator in the denso alternator is, but if it did run away like that, you cook your computer and the big fan thingy attached to your motor stops moving and it gets real quiet. I'm not sure, but I think that an overvoltage condtion is much more likely with a mechanical voltage regulator. Anyone out there know more about these things? Brian Trubee My feeble understanding is that, in the alternator the flux field is spinning, as opposed to being stationary in the generator, and voltage output is controlled by how much voltage the regulator puts into the armature through the brushes and slip rings. So to reduce the output voltage to near zero you must cut the voltage to the brushes. No flux field, no output. So, a heavy double pole single throw switch in series with the brushes, should be adequate to eliminate the alternator as a problem. If one brush is just grounded inside the alternator, then battery supply to the regulator could go through the same switch. Then you would have nothing in and nothing out. A big diode on the alternator output would isolate the alternator from the battery(s) so a total meltdown could not take the battery(s) out with the alternator failure. Lynn E. Hanover --part1_d033.6e29c804.39cb7ff3_boundary Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable

In a message dated 9/22/2010 11:07:43 A.M. Eastern Standard Time,=20 bktrub@aol.com writes:

I don't know how likely an overvoltage condition is with the intern= al=20 regulator in the denso alternator is, but if it did run away like that,= you=20 cook your computer and the big fan thingy attached to your motor stops= moving=20 and it gets real quiet.

I'm not sure, but I think that an overvoltage condtion is much more= =20 likely with a mechanical voltage regulator. Anyone out there know = more=20 about these things?

Brian Trubee

My feeble understanding is that, in the alternator the flux field is= =20 spinning, as opposed to being stationary in the generator, and voltage out= put is=20 controlled by how much voltage the regulator puts into the armature throug= h the=20 brushes and slip rings.

So to reduce the output voltage to near zero you must cut the voltage= to=20 the brushes. No flux field, no output.

So, a heavy double pole single throw switch in series with the brushe= s,=20 should be adequate to eliminate the alternator as a problem.

If one brush is just grounded inside the alternator, then battery sup= ply to=20 the regulator could go through the same switch. Then you would have nothin= g in=20 and nothing out.

A big diode on the alternator output would isolate the alternator fro= m the=20 battery(s) so a total meltdown could not take the battery(s) out with the= =20 alternator failure.

Lynn E. Hanover

--part1_d033.6e29c804.39cb7ff3_boundary--