X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from web111513.mail.gq1.yahoo.com ([67.195.15.205] verified) by logan.com (CommuniGate Pro SMTP 5.2.13) with SMTP id 3555415 for flyrotary@lancaironline.net; Sun, 22 Mar 2009 10:04:03 -0400 Received-SPF: none receiver=logan.com; client-ip=67.195.15.205; envelope-from=roundrocktom@yahoo.com Received: (qmail 36148 invoked by uid 60001); 22 Mar 2009 14:03:27 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.com; s=s1024; t=1237730607; bh=8CGtV9Wpplh6ADrHijPOCDaduyNnQAniGXOVIbXeIPQ=; h=Message-ID:X-YMail-OSG:Received:X-Mailer:Date:From:Subject:To:MIME-Version:Content-Type; b=2k2dwGZl1JAjcH348V9S4mhi3rBYqInv4gCz0OaO0IzDbx2H68Kiqcw3YkOlsFqRS+W0gswrrYRbsk2ueJ2/hj5pIlao9D5sYxvUfqZiaPN8mexG5fsIWib7qAtTZfHBnUPrIBMgfHiLdOKLindyoBCqMDf05mpUiLLYxmv3Co8= DomainKey-Signature:a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com; h=Message-ID:X-YMail-OSG:Received:X-Mailer:Date:From:Subject:To:MIME-Version:Content-Type; b=V0IjrAzeIOxxF+Hkik/mR/62H4gkqWTHahnqsjUu6LOFNhns+5ZrbFstwxQWX2iwwk0ohtt60slqsu25dkI1Aw1m7fy1DiuhRyZ+hwLVwFlZPeGFlQKoyBj7pHDC/mRiH5K2CdABBd2aOqGqxEiX6Dd2eWpAnPBVQFBKG5xBfxQ=; Message-ID: <220742.35995.qm@web111513.mail.gq1.yahoo.com> X-YMail-OSG: aiBVjuQVM1nC5eUqBWUkY96yiiceLVO6SqD.tCuueWgt0zVeooWjhkMvoNhPBlGhjw9xef5Ht93LI2zLmieVUaXT6GY7ZAstXaRGxqVEqBp6d7Mp3JsaCAd5rBqskHynob1Hck8Wxgzlch0xUBbKvcHJuz4Y211HSAKxpqKgU7xaPXL7Zlq7IOUgwSJ6bMnRFd2Ca_Eb9YqMkd6mv0DVjBtHqDcKjxt1qlmh4_mZ7jI0TSfifAZK0Vy835wXJIq77JdBH9NU7CniWUfo Received: from [66.68.44.99] by web111513.mail.gq1.yahoo.com via HTTP; Sun, 22 Mar 2009 07:03:26 PDT X-Mailer: YahooMailClassic/5.1.20 YahooMailWebService/0.7.289.1 Date: Sun, 22 Mar 2009 07:03:26 -0700 (PDT) From: thomas walter Subject: Re: Alternator (Off topic) To: Rotary motors in aircraft MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="0-2086287384-1237730606=:35995" --0-2086287384-1237730606=:35995 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable Jim, The field is either on or off.=A0=20 The regulator would create too much heat with a linear function, so solutio= n is just a 'switch' function in the regulator IC. Battery does the trick in smoothing the voltage. George -- simple test is with the engine idling, kick on the lights/fan... = note the rpm drop. That is the load of the alternator turning on. Newer vehicles will have add= itional inputs to the alternator so it knows when the AC is on, or when you= kick WOT (wide open throttle) as it will disconnect the alternator and A/C= off for a brief amount of time.=A0=A0=A0 Also a simple battery test is to = (in the car) kick on all loads at idle.... if the engine dies, battery rese= rve isn't there and time to replace 'em.=A0=A0=20 Tom 1) Re: Alternator (Off topic) =A0 =A0 by James Maher George,=0AI'm sorry to disagree with you but you are quite mistaken in your= belief about the=0Aalternator function.=0AThe alternator output is mostly = a function of load because of the voltage regulator,=0Awhose function is to= keep the voltage constant with changes in load and RPM.=0AIt performs this= function by varying the field current in the alternator.=0AIf fact this is= one of the many advantages of the alternator over a generator.=0AThe alter= nator's voltage output is also more or less constant regardless of engine R= PM, also due to the regulator's function.=0AYou said "The alternator charge= s the battery - which in turn runs the accessories".=0AThis is not exactly = true. If the battery voltage is below that of the alternator output=0Athen = yes the alternator will function to charge the battery,=0Ahowever if the ba= ttery is fully charged then the alternator will not be=0Acharging the batte= ry but will provide the necessary power to drive any=0Aother loads connecte= d to the system.=0ASo reducing the electrical load on the system will indee= d reduce the mechanical load on=0Athe engine thereby using less overall ene= rgy.=0AHope this clarifies your misconception.=0ADon't feel bad, many peopl= e do not fully understand even the most=0Asimple of electrical devices and = the alternator/regulator charging=0Asystem is fairly complex.=0AJim =0A=0A=0A --0-2086287384-1237730606=:35995 Content-Type: text/html; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable
Jim,

The field is either on or off.&nb= sp;

The regulator would create too much heat with a linear function= , so solution is just a 'switch' function in the regulator IC.

Batte= ry does the trick in smoothing the voltage.

George -- simple test is= with the engine idling, kick on the lights/fan... note the rpm drop.
Th= at is the load of the alternator turning on. Newer vehicles will have addit= ional inputs to the alternator so it knows when the AC is on, or when you k= ick WOT (wide open throttle) as it will disconnect the alternator and A/C o= ff for a brief amount of time.    Also a simple battery test= is to (in the car) kick on all loads at idle.... if the engine dies, batte= ry reserve isn't there and time to replace 'em.  

Tom
=





1)= Re: Alternator (Off topic)
    by James Maher <d= elta11xd@att.net>

George,
=0A
I'm sorry to disa= gree with you but you are quite mistaken in your belief about the
=0A<= div>alternator function.
=0A
The alternator output is mostly a fun= ction of load because of the voltage regulator,
=0A
whose function= is to keep the voltage constant with changes in load and RPM.
=0AIt performs this function by varying the field current in the alternator.<= /div>=0A
If fact this is one of the many advantages of the alternator o= ver a generator.
=0A
The alternator's voltage output is also more = or less constant regardless of engine RPM, also due to the regulator's func= tion.
=0A
You said "The alternator charges the battery - which in = turn runs the accessories".
=0A
This is not exactly true. If the b= attery voltage is below that of the alternator output
=0A
then yes= the alternator will function to charge the battery,=0Ahowever if the batte= ry is fully charged then the alternator will not be=0Acharging the battery = but will provide the necessary power to drive any=0Aother loads connected t= o the system.
=0A
So reducing the electrical load on the system wi= ll indeed reduce the mechanical load on
=0A
the engine thereby usi= ng less overall energy.
=0A
Hope this clarifies your misconception= .
=0A
Don't feel bad, many people do not fully understand even the= most=0Asimple of electrical devices and the alternator/regulator charging= =0Asystem is fairly complex.
=0AJim


=0A=0A --0-2086287384-1237730606=:35995--