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<DIV><SPAN class=296374515-11012006><FONT face=Arial color=#0000ff>Hi George and
Gang,</FONT></SPAN></DIV>
<DIV><SPAN class=296374515-11012006><FONT face=Arial color=#0000ff>Lacking a
copy of one of the fancy e-simulator tools, you can go to <A
href="http://www.aveox.com">www.aveox.com</A>, and find their free simulator. It
ain't fancy, but if you adjust the number of NiCad cells used by default to
get 34 or 35V, then it produces meaningful results. Plug in the numbers for
Kv, winding resistance, and no-load current of your motor (should all be
available on the mfgr's website and to any who don't shame on you!) and you will
get a good +/- 10% estimate of the current you should expect with a given prop.
The tool works, and can save you money and grief. Most importantly, use a
current meter the very first time you try any new prop size! Sears sells a nifty
clamp-on DC current meter for $50. RVP, what was the part number on that
critter, again?</FONT></SPAN></DIV>
<DIV><SPAN class=296374515-11012006><FONT face=Arial
color=#0000ff>later,</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>George
Miller<BR><B>Sent:</B> Wednesday, January 11, 2006 7:25 AM<BR><B>To:</B>
patternrules@earthlink.net; NSRCA Mailing List<BR><B>Subject:</B> Re:
[NSRCA-discussion] Electric Power Consumption<BR><BR></FONT></DIV>
<DIV><FONT face=Arial>Thanks, Steve- I picked the Actro 32-3 because I'm going
to use one in my Ion and I therefore knew that it would run on the 5s4p
packs. I picked the prop at the upper end of the Hobby Lobby
range...didn't do the RPM/volt calculation...but if that is true, even with
only only one pack(5S), I'd be pushing 10K rev's ..... My Plettenberg turns
about 9K with 42 Volts. As to the cell count--- at 1.5 volt per cell, 26
nicad cells is about 39 volts...and since I knew the actro was run in heli's
with the 10S setup, I thought that was pretty close.....</FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT face=Arial>I'm not trying to be contentious, I'm just trying to
learn how to do these calculations properly in the future. Its all well
and good to say use a proven system, but someone has to "prove" each one as
they come available. I guess I need much more info before I become
a pioneer<G>.</FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT face=Arial>G</FONT></DIV>
<BLOCKQUOTE
style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=patternrules@earthlink.net
href="mailto:patternrules@earthlink.net">Steven Maxwell</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A
title=nsrca-discussion@lists.nsrca.org
href="mailto:nsrca-discussion@lists.nsrca.org">NSRCA Mailing List</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Tuesday, January 10, 2006 11:22
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> RE: [NSRCA-discussion]
Electric Power Consumption</DIV>
<DIV><BR></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>
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