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<DIV><SPAN class=812563516-11012006><FONT face=Arial color=#0000ff>I had a few
seconds, so I looked the motor constsnts up on the Hobby Lobby site (I had
to guess at the no-load current, with somethinng typical for this size motor and
# of winds) and plugged into the virtual testbench at Aveox.</FONT></SPAN></DIV>
<DIV><SPAN class=812563516-11012006><FONT face=Arial color=#0000ff>With an 11-5
prop turning at about 18,000 RPM, the motor will pull 60A from a ten-cell LiPo.
It's a good helicopter motor. For Pattern, you'd need a gearbox or belt
reduction. The direct-drive current with a 17-12 depended entirely on how
the battery crushed under such an oppressive load. A wild guess would be around
150 A.</FONT></SPAN></DIV>
<DIV><SPAN class=812563516-11012006><FONT face=Arial
color=#0000ff></FONT></SPAN> </DIV>
<DIV><SPAN class=812563516-11012006><FONT face=Arial
color=#0000ff>later,</FONT></SPAN></DIV>
<DIV><SPAN class=812563516-11012006><FONT face=Arial
color=#0000ff>Dean</FONT></SPAN></DIV>
<DIV> </DIV>
<P><FONT face="Times New Roman">Dean Pappas</FONT> <BR><FONT
face="Times New Roman">Sr. Design Engineer</FONT> <BR><FONT
face="Times New Roman">Kodeos Communications</FONT> <BR><FONT
face="Times New Roman">111 Corporate Blvd.</FONT> <BR><FONT
face="Times New Roman">South Plainfield, N.J. 07080</FONT> <BR><FONT
face="Times New Roman">(908) 222-7817 phone</FONT> <BR><FONT
face="Times New Roman">(908) 222-2392 fax</FONT> <BR><FONT
face="Times New Roman">d.pappas@kodeos.com</FONT> </P>
<BLOCKQUOTE dir=ltr style="MARGIN-RIGHT: 0px">
<DIV class=OutlookMessageHeader dir=ltr align=left><FONT
face=Tahoma>-----Original Message-----<BR><B>From:</B>
nsrca-discussion-bounces@lists.nsrca.org
[mailto:nsrca-discussion-bounces@lists.nsrca.org]<B>On Behalf Of </B>Steven
Maxwell<BR><B>Sent:</B> Wednesday, January 11, 2006 12:22 AM<BR><B>To:</B>
NSRCA Mailing List<BR><B>Subject:</B> RE: [NSRCA-discussion] Electric Power
Consumption<BR><BR></FONT></DIV>
<DIV>
<DIV> I'm trying to learn some of this also, so take anything I might say
with a grain of salt, I will be using a standard setup this spring that many
have already used.</DIV>
<DIV> From Hobby-Lobby site for Actro 32-3</DIV>
<DIV>
<DIV align=left><FONT face="Verdana, Arial, Helvetica, sans-serif"
color=#ff0000>For 14-26 cells in propeller models and 28-32 cells in
helicopters. Propeller range is 13" to 18" in diameter. This 3 turn motor has
an RPM/Volt of 555, resistance of 34 mOhm. Maximum efficiency of about 89% in
the 50-95 amp draw range. Power output in the 550-2000 watt
range.</FONT></DIV></DIV>
<DIV> Sounds like you used 5S4P in series 42 volts X <FONT
face=Verdana color=#ff0000>RPM/Volt of 555<FONT color=#000000>=23,310
rpm.</FONT></FONT></DIV>
<DIV><FONT face=Verdana color=#ff0000><FONT color=#000000> I tried to
run a setup on motor calc but there data is so outa date nothing there to use
maybe somehas elecalc to do figures for you.</FONT></FONT></DIV>
<DIV><FONT face=Verdana> The other thing I have found on Hobby Lobby site
is most of the time they talk about cells is to NiMh or NiCd if Lipo's they
generally say so.</FONT></DIV>
<DIV><FONT face=Verdana> </FONT> Hope this will generate some info
and the best of luck.</DIV>
<DIV> Steve Maxwell</DIV></DIV>
<DIV> </DIV>
<BLOCKQUOTE
style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid">
<DIV style="FONT: 10pt Arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=glmiller3@cox.net href="mailto:glmiller3@cox.net">George Miller</A>
</DIV>
<DIV style="FONT: 10pt arial"><B>To: </B><A title=discussion@nsrca.org
href="mailto:discussion@nsrca.org">discussion@nsrca.org</A></DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> 1/11/2006 1:32:01 AM </DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> [NSRCA-discussion] Electric
Power Consumption</DIV>
<DIV><BR></DIV>
<DIV><FONT face=Arial>I have a problem with an electric conversion which
while not precisely pattern related, I'm sure will be applicable to electric
pattern problems...so I'll ask it here.</FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT face=Arial>I am trying to convert a Showtime from YS 110 4 cycle
power to electric power. After looking around the web, I got an Actro
32-3 - which is a popular motor for the Ion electric helicopter. I
know that this motor runs well with available ESC's on 5S4P lithium packs,
so I set it up with a 17X12 APC e prop and a 77amp ESC from Hobby
Lobby ( esc and prop recommended on their website).
To make a long story short, the ESC litterally burned up 30 seconds into the
first flight....but BOY WHAT POWER for that 30
seconds<G>!!!</FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT face=Arial>OK, so I'm thinking that burning up probably indicates
a problem.....and I start to investigate...I hook up a watts-up to my Focus
II with a Plettenberg 30-10 and a 21X12 APC and it pulls about 65 amps
at full throttle on the bench....Then I set up the Showtime and it tops 75
amps at half throttle!! HMMM, so there is the problem....Now I try to make
changes to decrease the amperage -- larger prop and smaller prop---no major
change, then I tried just using a 5 cell pack cutting voltage in
half...still about the same....so the question is: How do you adjust
the current drawn by an electric motor? Can this set up be
salvaged...Where did I go wrong and how can I avoid this in the future?
</FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT face=Arial>TIA for your help and the benefit of your
experience!</FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT
face=Arial>George</FONT></DIV></BLOCKQUOTE></BLOCKQUOTE></BODY></HTML>