X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mfep5.connect.com.au ([210.8.231.141] verified) by logan.com (CommuniGate Pro SMTP 4.3c5) with ESMTP id 944690 for flyrotary@lancaironline.net; Sun, 15 May 2005 09:07:34 -0400 Received-SPF: none receiver=logan.com; client-ip=210.8.231.141; envelope-from=ianb@ozzienet.net Received: from MAIN (unknown [203.129.128.200]) by mfep5.connect.com.au (Postfix) with SMTP id 6BA52B4C6 for ; Sun, 15 May 2005 23:06:45 +1000 (EST) Message-ID: <012d01c5594e$f550c6c0$c88081cb@MAIN> From: "Ian Beadle" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Hot Alternator??? Date: Sun, 15 May 2005 21:06:49 +0800 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_012A_01C55992.02940700" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2180 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 This is a multi-part message in MIME format. ------=_NextPart_000_012A_01C55992.02940700 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Message ----- Original Message -----=20 From: Al Gietzen=20 To: Rotary motors in aircraft=20 Sent: Saturday, May 14, 2005 11:29 PM Subject: [FlyRotary] Re: Hot Alternator??? For those of you in the know, is it normal for an alternator to seep = current and get warm when the field coil is powered up? Is this = something I need to fix? If so, should I cancel my trip? I think it = has probably been going on for a long time but... The field current is controlled by the regulator, which is usually = internal. The regulator will only allow field current if the armature is = spinning and bat. below about 14 volts. A small amount of current is = allowed at start up via the little red light to give initial voltage. In short get the regulator checked. Ian Beadle. Ian; With the alternator not running, the battery voltage will always be = below 14 volts; even with the charger on, so the field current will = flow. Dave has modified the internal connection the same way I did to = provide external feed to the field windings. This does not run through = the warning light. So with battery voltage to the field, alternator not = running; I estimate it will draw 2-3 amps. Plenty to make the = alternator pretty warm after awhile. Also, I don't think tripping a 5 amp breaker in field circuit = indicates anything wrong. With the battery a bit low and a, say, 60A = alternator spinning, the field could draw 5 amps. I use a 7.5A breaker = on my field current circuit. Al There should be a relay connected to D on the alternator, this = ensures that the field is only powered when the alternator is spinning. Ian=20 -------------------------------------------------------------------------= ----- Internal Virus Database is out-of-date. Checked by AVG Anti-Virus. Version: 7.0.308 / Virus Database: 266.11.6 - Release Date: 6/05/2005 ------=_NextPart_000_012A_01C55992.02940700 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Message
 
----- Original Message -----
From:=20 Al = Gietzen=20
Sent: Saturday, May 14, 2005 = 11:29=20 PM
Subject: [FlyRotary] Re: Hot=20 Alternator???

For those of you in the = know, is it=20 normal for an alternator to seep current and get warm when the field = coil is=20 powered up?  Is this something I need to fix?  If so, = should I=20 cancel my trip?  I think it has probably been going on for a = long time=20 but...


The field current is = controlled=20 by the regulator, which is usually internal. The regulator will only = allow=20 field current if the armature is spinning and bat. below about 14 = volts. A=20 small amount of current is allowed at start up via the little red = light to=20 give initial voltage.

In short get the = regulator=20 checked.

 

Ian = Beadle.

 

Ian;

 

With = the=20 alternator not running, the battery voltage will always be below 14 = volts;=20 even with the charger on, so the field current will flow.  Dave = has=20 modified the internal connection the same way I did to provide = external feed=20 to the field windings.  This does not run through the warning=20 light.  So with battery voltage to the field, alternator not = running; I=20 estimate it will draw 2-3 amps.  Plenty to make the alternator = pretty=20 warm after awhile.

 

Also, I = don=92t=20 think tripping a 5 amp breaker in field circuit indicates anything=20 wrong.  With the battery a bit low and a, say, 60A alternator = spinning,=20 the field could draw 5 amps.  I use a 7.5A breaker on my field = current=20 circuit.

 

Al

 

There = should be a=20 relay connected to  D on the alternator, this ensures that the = field is=20 only powered when the alternator is=20 spinning.

Ian

Internal Virus Database is out-of-date.
Checked by AVG=20 Anti-Virus.
Version: 7.0.308 / Virus Database: 266.11.6 - Release = Date:=20 6/05/2005
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