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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>
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style="BORDER-LEFT: #000000 2px solid; PADDING-LEFT: 5px; PADDING-RIGHT: 0px; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="FONT: 10pt arial; BACKGROUND: #e4e4e4; font-color: black"><B>From:</B>
<A title=josephperkel@yahoo.com href="mailto:josephperkel@yahoo.com">Joe
Perkel</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A
title=personal_submersibles@psubs.org
href="mailto:personal_submersibles@psubs.org">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>
<DIV><BR></DIV>
<DIV
style="BACKGROUND-COLOR: #fff; FONT-FAMILY: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; COLOR: #000; FONT-SIZE: 12pt">
<DIV id=yiv7646271124>
<DIV>
<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 id=yiv7646271124yui_3_13_0_rc_1_1_1381888951465_3384
href="http://www.baldor.com/support/literature_load.asp?LitNumber=FL1210"
rel=nofollow
target=_blank>http://www.baldor.com/support/literature_load.asp?LitNumber=FL1210</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>
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