Subject: [Shop-talk] Alternator terminals

From: Dave Cavanaugh <[email-masked]>
Date: Wed, 13 Apr 2016 19:33:33 -0700

This is a multi-part message in MIME format.
--===============0951338507701055684==
 boundary="------------070605060907050405090300"

This is a multi-part message in MIME format.
--------------070605060907050405090300
Content-Transfer-Encoding: 7bit

Our PE department got rid of a bunch of exercise equipment.  I pulled a 
nice commercial exercise bike out of the metal recycle and had the kids 
strip all the plastic off of it, and I found the guts of it are an 
automotive type alternator and a big resistor.  I want to hook it up as 
a current source for a battery charger/light bulbs/ammeter/something to 
give the kids an idea of how much actual work a KW is.

The alternator is a Mando 38611-101.   A picture of the alternator is here:

http://www.gympart.com/itemdesc.aspx?ic=LCA10

If you look at the picture on the link above and rotate it 90 degrees so 
the black plastic part is at 6:00, it has the following terminals:
On the black plastic part, "Ex" and "S".

On the main body of the alternator, clockwise from 8:00 the terminals 
are "L2", "P", "B" and "E".   There is also a ground terminal.

If you look a this chart,

> http://dasko.co.nz/articles/alternator-terminals-explained

It looks like all I would need to hook up to would be the "B" terminal 
and the ground and I can ignore the rest.

Do I have this right?

On an automotive alternator how fast does it normally have to spin to 
put out 12V?

Thanks
Dave

--------------070605060907050405090300
Content-Transfer-Encoding: 8bit

<html>
  <head>

    <meta http-equiv="content-type" content="text/html; charset=utf-8">
  </head>
  <body bgcolor="#FFFFFF" text="#000000">
    Our PE department got rid of a bunch of exercise equipment.  I
    pulled a nice commercial exercise bike out of the metal recycle and
    had the kids strip all the plastic off of it, and I found the guts
    of it are an automotive type alternator and a big resistor.  I want
    to hook it up as a current source for a battery charger/light
    bulbs/ammeter/something to give the kids an idea of how much actual
    work a KW is.  <br>
    <br>
    The alternator is a Mando 38611-101.   A picture of the alternator
    is here:<br>
    <br>
    <a class="moz-txt-link-freetext" href="http://www.gympart.com/itemdesc.aspx?ic=LCA10">http://www.gympart.com/itemdesc.aspx?ic=LCA10</a><br>
    <br>
    If you look at the picture on the link above and rotate it 90
    degrees so the black plastic part is at 6:00, it has the following
    terminals:<br>
    On the black plastic part, "Ex" and "S".  <br>
    <br>
    On the main body of the alternator, clockwise from 8:00 the
    terminals are "L2", "P", "B" and "E".   There is also a ground
    terminal.  <br>
    <br>
    If you look a this chart,<br>
    <br>
    <blockquote type="cite"><a class="moz-txt-link-freetext" href="http://dasko.co.nz/articles/alternator-terminals-explained">http://dasko.co.nz/articles/alternator-terminals-explained</a></blockquote>
    <br>
    It looks like all I would need to hook up to would be the "B"
    terminal and the ground and I can ignore the rest.  <br>
    <br>
    Do I have this right?  <br>
    <br>
    On an automotive alternator how fast does it normally have to spin
    to put out 12V?  <br>
    <br>
    Thanks<br>
    Dave<br>
    <br>
    <br>
    <br>
    <br>
    <p class="MsoNormal"><br>
      <o:p></o:p><o:p></o:p><br>
    </p>
    <br>
    <br>
  </body>
</html>

--------------070605060907050405090300--

--===============0951338507701055684==
Content-Transfer-Encoding: 7bit
Content-Disposition: inline

_______________________________________________

[email-masked]
Archive: http://www.team.net/archive

--===============0951338507701055684==--

---

From: "Randall" <[email-masked]>
Date: Thu, 14 Apr 2016 02:18:55 -0700

> terminal and the ground and I can ignore the rest.  
> 
> Do I have this right?  

You can try that, but I suspect the Ex terminal needs to get current through the warning lamp (which provides excitation when the
alternator first starts turning), and the S terminal needs to get battery voltage (The 'sense' input to the voltage regulator).  You
can use a resistor instead of the lamp, if you want, but you'll still need an external source of 12v to get it working (and a switch
to stop it from drawing current all the time).  Just jumper the S terminal to the B terminal, though.

> On an automotive alternator how fast does it normally have to 
> spin to put out 12V?  

They'll usually put out something with the engine idling, maybe 1000-1200 rpm at the alternator.  Full output requires more, though,
generally something like 5000-7000 at the alternator.

Randall

[email-masked]

---

From: Dave Cavanaugh <[email-masked]>
Date: Thu, 14 Apr 2016 19:18:52 -0700

Thanks; I'll give that a try.

We tried just connecting to the B and ground terminals with a meter and 
could never get higher than 5 VDC no matter how hard we pedaled and when 
I put a 12 volt lamp in the circuit it didn't even start to glow.

On 4/14/2016 2:18 AM, Randall wrote:
> Donate: http://www.team.net/donate.html
> Suggested annual donation  $12.96
> Forums: http://www.team.net/forums
> Unsubscribe/Manage: http://autox.team.net/mailman/options/shop-talk/[email-masked]
>
>

[email-masked]