<html><body bgcolor="#FFFFFF"><div><br></div><div><br><br>Sent from my iPhone</div><div><br>On Oct 16, 2013, at 2:08 PM, Joe Perkel <<a href="mailto:josephperkel@yahoo.com">josephperkel@yahoo.com</a>> wrote:<br><br></div><div></div><blockquote type="cite"><div><table cellspacing="0" cellpadding="0" border="0"><tbody><tr><td valign="top">Dan,<br><br>What I was hoping to find was BLDC motors matching 36v 1800 - 3600 rpm, 1/2 to 2 hp range. They don't seem to be out there.<br><br>I have matched up brushed motors with those specs at both Baldor and Leeson with the appropriate face plates. But, then we are back to the same large / heavy motors at least there in the $500 range.<br><br>You have the standard motors on Persistence, what are the size and pitch of the respective props?<br><br>I'm going to just have to suck it up and draw these up with new Kort nozzles.<br><br>Thanks!<br><br>Joe<br><br>Sent from Yahoo! Mail for iPad</td></tr></tbody></table> <div id="_or
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<span style="font-weight:bold">From:</span>
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Dan H. <<a href="mailto:jumachine@comcast.net">jumachine@comcast.net</a>>; <br>
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<span style="font-weight:bold">To:</span>
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Personal Submersibles General Discussion <<a href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>>; <br>
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<span style="font-weight:bold">Subject:</span>
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Re: [PSUBS-MAILIST] DC Systems Primer <br>
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<span style="font-weight:bold">Sent:</span>
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Wed, Oct 16, 2013 1:48:13 PM <br>
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<div><font size="2" face="Arial">Those high voltage DC motors are designed for
variable speed drives where the power is first line voltage AC then converted to
DC through a motor controller for accurate motor speeds and
torque. They aren't practical for a battery powered
system.</font></div>
<div><font size="2" face="Arial"></font> </div>
<div><font size="2" face="Arial">For battery powered systems your probably better
off to stick to the lower voltage motors. With an inverter I guess you
could convert the battery power to high voltage AC then convert it to DC, but
I'm pretty sure you'd find it impractical with the extra equipment.
</font></div>
<div><font size="2" face="Arial"></font> </div>
<div><font size="2" face="Arial">It's hard to beat golf cart controllers for speed
regulation and there's tons of them out there. Battery powered floor
scrubbers use a variety of DC motors too. </font></div>
<div><font size="2" face="Arial"></font> </div>
<div><font size="2" face="Arial">Dan H.</font></div>
<div><font size="2" face="Arial"></font> </div>
<blockquote style="BORDER-LEFT:#000000 2px solid;PADDING-LEFT:5px;PADDING-RIGHT:0px;MARGIN-LEFT:5px;MARGIN-RIGHT:0px;">
<div class="yqt5283399738" id="yqt73347"><div style="FONT:10pt arial;">----- Original Message ----- </div>
<div style="FONT:10pt arial;BACKGROUND:#e4e4e4;"><b>From:</b>
<a rel="nofollow" shape="rect" title="josephperkel@yahoo.com" ymailto="mailto:josephperkel@yahoo.com" target="_blank" href="javascript:return">Joe
Perkel</a> </div>
<div style="FONT:10pt arial;"><b>To:</b> <a rel="nofollow" shape="rect" title="personal_submersibles@psubs.org" ymailto="mailto:personal_submersibles@psubs.org" target="_blank" href="javascript:return">Psubbers Mailist</a> </div>
<div style="FONT:10pt arial;"><b>Sent:</b> Tuesday, October 15, 2013 11:02
PM</div>
<div style="FONT:10pt arial;"><b>Subject:</b> [PSUBS-MAILIST] DC Systems
Primer</div>
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<div id="yiv7646271124">
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<div style="BACKGROUND-COLOR:rgb(255,255,255);FONT-FAMILY:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;COLOR:rgb(0,0,0);FONT-SIZE:12pt;">
<div id="yiv7646271124yui_3_13_0_rc_1_1_1381888951465_3254">Since my Navy "A"
school is some 30+ years ago, I need a little help in trying to understand
and match up something close to Georges motors. What I dont understand is
why is there such an array of DC motors in the 1 - 3 hp range with wildly
varing input voltages?</div>
<div id="yiv7646271124yui_3_13_0_rc_1_7_1381888951465_18"> </div>
<div id="yiv7646271124yui_3_13_0_rc_1_7_1381888951465_19">If you notice those
Tecnadyne thrusters have stupendous input voltages up to 330vdc. I dont
understand why and need a primer on DC systems for this application. Can
anyone point me to one?</div>
<div id="yiv7646271124yui_3_13_0_rc_1_1_1381888951465_3278"> </div>
<div id="yiv7646271124yui_3_13_0_rc_1_7_1381888951465_7">What I'm trying to do
is to slim down the housing, get more bollard thrust from the prop by
adding a real kort nozzle, and use a mag coupling instead of a shaft seal, all
else remaining essentially the same.</div>
<div id="yiv7646271124yui_3_13_0_rc_1_7_1381888951465_9"> </div>
<div id="yiv7646271124yui_3_13_0_rc_1_7_1381888951465_10">I want to slim down
Georges T-Rex cans with similar power specs, but new and improved components,
keeping the items conducive to homebuilding, like the housings and mountings,
electrical penetrators, shaft seals if I cant do mag couplings. </div>
<div id="yiv7646271124yui_3_13_0_rc_1_7_1381888951465_15"> </div>
<div id="yiv7646271124yui_3_13_0_rc_1_7_1381888951465_16">What I've found so far
<a rel="nofollow" shape="rect" id="yiv7646271124yui_3_13_0_rc_1_1_1381888951465_3384" target="_blank" href="http://www.baldor.com/support/literature_load.asp?LitNumber=FL1210"><a href="http://www.baldor.com/support/literature_load.asp?LitNumber=FL1210">http://www.baldor.com/support/literature_load.asp?LitNumber=FL1210</a></a>
fractional hp and up to 3 hp @ 1800 rpm but, here again @ 320vdc !?</div>
<div> </div>
<div>Whats attractive about this one is the dimensions, 6.5" on the
mounting flange would fit quite nicely in the 6 nom SCH40 pipe which is
6.625"</div>
<div> </div>
<div>But I dont know what im doing with regard to the input voltage /
output power / torque relationship and how to match this all up
correctly. All Ive confirmed so far is that Georges motors were TENV
(totally enclosed non-ventilated), 36vdc @ 1800 to 3600 rpm for 1/2 and 3 hp
respectively.</div>
<div> </div>
<div>Joe</div>
<div id="yiv7646271124yui_3_13_0_rc_1_7_1381888951465_12"> </div>
<div id="yiv7646271124yui_3_13_0_rc_1_7_1381888951465_13"> </div></div></div></div></div></div>
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