<html><body><div style="color:#000; background-color:#fff; font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px"><div id="yui_3_16_0_1_1433637403143_3270"><span>Thanks Ken,</span></div><div id="yui_3_16_0_1_1433637403143_3269"><span id="yui_3_16_0_1_1433637403143_3268">I was nearly going to ask you to comment in my post.</span></div><div id="yui_3_16_0_1_1433637403143_3269"><span id="yui_3_16_0_1_1433637403143_3336">Is there an alternative to capacitors or to the electrolitic capacitors usually used?</span></div><div id="yui_3_16_0_1_1433637403143_3269"><span>I was looking at this option.</span></div><div id="yui_3_16_0_1_1433637403143_3269" dir="ltr"><span id="yui_3_16_0_1_1433637403143_3502"><a href="http://www.dialelectrolux.ru/files/file/electronicon/e61-data-charts-engl-deut.pdf" id="yui_3_16_0_1_1433637403143_3501">http://www.dialelectrolux.ru/files/file/electronicon/e61-data-charts-engl-deut.pdf</a><br></span></div><div id="yui_3_16_0_1_1433637403143_3269" dir="ltr">Alan</div><br> <div style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 16px;" id="yui_3_16_0_1_1433637403143_3340"> <div style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 16px;" id="yui_3_16_0_1_1433637403143_3339"> <div dir="ltr" id="yui_3_16_0_1_1433637403143_3338"> <hr size="1" id="yui_3_16_0_1_1433637403143_3642"> <font size="2" face="Arial" id="yui_3_16_0_1_1433637403143_3337"> <b><span style="font-weight:bold;">From:</span></b> Ken Martindale via Personal_Submersibles <personal_submersibles@psubs.org><br> <b><span style="font-weight: bold;">To:</span></b> 'Personal Submersibles General Discussion' <personal_submersibles@psubs.org> <br> <b><span style="font-weight: bold;">Sent:</span></b> Sunday, June 7, 2015 12:19 PM<br> <b id="yui_3_16_0_1_1433637403143_3342"><span style="font-weight: bold;" id="yui_3_16_0_1_1433637403143_3341">Subject:</span></b> Re: [PSUBS-MAILIST] Dive report: Snoopy at Seneca<br> </font> </div> <div class="y_msg_container" id="yui_3_16_0_1_1433637403143_3347"><br><div id="yiv9053454032"><style>#yiv9053454032 #yiv9053454032 --
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#yiv9053454032 </style><div id="yui_3_16_0_1_1433637403143_3346"><div class="yiv9053454032WordSection1" id="yui_3_16_0_1_1433637403143_3345"><div class="yiv9053454032MsoNormal" id="yui_3_16_0_1_1433637403143_3344"><span style="font-size:11.0pt;" id="yui_3_16_0_1_1433637403143_3343">Adding extra capacitors helps reduce the magnitude of the inductive voltage spikes.</span></div><div class="yiv9053454032MsoNormal" id="yui_3_16_0_1_1433637403143_3355"><span style="font-size:11.0pt;"> </span></div><div class="yiv9053454032MsoNormal" id="yui_3_16_0_1_1433637403143_3349"><span style="font-size:11.0pt;" id="yui_3_16_0_1_1433637403143_3348">Ken Martindale.</span></div><div class="yiv9053454032MsoNormal" id="yui_3_16_0_1_1433637403143_3350"><span style="font-size:11.0pt;"> </span></div><div class="qtdSeparateBR"><br><br></div><div class="yiv9053454032yqt2172010875" id="yiv9053454032yqt94512"><div id="yui_3_16_0_1_1433637403143_3352"><div style="border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in;" id="yui_3_16_0_1_1433637403143_3351"><div class="yiv9053454032MsoNormal" id="yui_3_16_0_1_1433637403143_3354"><b><span style="font-size:11.0pt;">From:</span></b><span style="font-size:11.0pt;" id="yui_3_16_0_1_1433637403143_3353"> Personal_Submersibles [mailto:personal_submersibles-bounces@psubs.org] <b>On Behalf Of </b>Alan James via Personal_Submersibles<br clear="none"><b>Sent:</b> Saturday, June 06, 2015 6:48 PM<br clear="none"><b>To:</b> Personal Submersibles General Discussion<br clear="none"><b>Subject:</b> Re: [PSUBS-MAILIST] Dive report: Snoopy at Seneca</span></div></div></div><div class="yiv9053454032MsoNormal" id="yui_3_16_0_1_1433637403143_3465"> </div><div id="yui_3_16_0_1_1433637403143_3442"><div id="yiv9053454032yui_3_16_0_1_1433621245176_12450"><div class="yiv9053454032MsoNormal" style="background:white;" id="yui_3_16_0_1_1433637403143_3464"><span style="">Thanks for the report Alec, great stuff.</span></div></div><div id="yiv9053454032yui_3_16_0_1_1433621245176_12450"><div class="yiv9053454032MsoNormal" style="background:white;" id="yui_3_16_0_1_1433637403143_3463"><span style="" id="yui_3_16_0_1_1433637403143_3462">re the motor controllers; I've been reading a bit about inductance in long wire runs from battery to</span></div></div><div id="yiv9053454032yui_3_16_0_1_1433621245176_12450"><div class="yiv9053454032MsoNormal" style="background:white;" id="yui_3_16_0_1_1433637403143_3670"><span style="" id="yui_3_16_0_1_1433637403143_3669">motor controllers, that harms the capacitors on the controllers.</span></div></div><div id="yiv9053454032yui_3_16_0_1_1433621245176_12450"><div class="yiv9053454032MsoNormal" style="background:white;" id="yui_3_16_0_1_1433637403143_3461"><span style="" id="yui_3_16_0_1_1433637403143_3460">This could be a problem that is unique to our submarines & not an issue with things like golf carts</span></div></div><div id="yiv9053454032yui_3_16_0_1_1433621245176_12450"><div class="yiv9053454032MsoNormal" style="background:white;" id="yui_3_16_0_1_1433637403143_3459"><span style="">& wheel chairs.</span></div></div><div id="yiv9053454032yui_3_16_0_1_1433621245176_12450"><div class="yiv9053454032MsoNormal" style="background:white;" id="yui_3_16_0_1_1433637403143_3458"><span style="" id="yui_3_16_0_1_1433637403143_3457">My reading has been mainly about BLDC motor controllers but asume PWM controllers for brushed</span></div></div><div id="yiv9053454032yui_3_16_0_1_1433621245176_12450"><div class="yiv9053454032MsoNormal" style="background:white;" id="yui_3_16_0_1_1433637403143_3456"><span style="" id="yui_3_16_0_1_1433637403143_3455">motors would be similar. Because of the rapid switching on & off of the power to the motor, there is a</span></div></div><div id="yiv9053454032yui_3_16_0_1_1433621245176_12450"><div class="yiv9053454032MsoNormal" style="background:white;" id="yui_3_16_0_1_1433637403143_3454"><span style="" id="yui_3_16_0_1_1433637403143_3453">current surge hitting the capacitors & the longer the wire run, the more the power in the surge.</span></div></div><div id="yiv9053454032yui_3_16_0_1_1433621245176_12450"><div class="yiv9053454032MsoNormal" style="background:white;" id="yui_3_16_0_1_1433637403143_3452"><span style="" id="yui_3_16_0_1_1433637403143_3451">A water analogy would be turning a valve off suddenly as washing machines do, sometimes with</span></div></div><div id="yiv9053454032yui_3_16_0_1_1433621245176_12450"><div class="yiv9053454032MsoNormal" style="background:white;" id="yui_3_16_0_1_1433637403143_3450"><span style="" id="yui_3_16_0_1_1433637403143_3671">a "thunk" sound & a rattle of the pipes.</span></div></div><div id="yiv9053454032yui_3_16_0_1_1433621245176_12450"><div class="yiv9053454032MsoNormal" style="background:white;" id="yui_3_16_0_1_1433637403143_3449"><span style="" id="yui_3_16_0_1_1433637403143_3448">Hugh mentioned he had problems with his Curtis BLDC motor controllers.</span></div></div><div id="yiv9053454032yui_3_16_0_1_1433621245176_12450"><div class="yiv9053454032MsoNormal" style="background:white;" id="yui_3_16_0_1_1433637403143_3447"><span style="" id="yui_3_16_0_1_1433637403143_3446">Attached is the problem & solution, which is to put capacitors in parrallel along the battery wire; </span></div></div><div id="yiv9053454032yui_3_16_0_1_1433621245176_12450"><div class="yiv9053454032MsoNormal" style="background:white;" id="yui_3_16_0_1_1433637403143_3445"><span style="" id="yui_3_16_0_1_1433637403143_3672">however there must be a better way.</span></div></div><div id="yiv9053454032yui_3_16_0_1_1433621245176_12450"><div class="yiv9053454032MsoNormal" style="background:white;" id="yui_3_16_0_1_1433637403143_3444"><span style="" id="yui_3_16_0_1_1433637403143_3673">Regards Alan</span></div></div><div id="yiv9053454032yui_3_16_0_1_1433621245176_12450"><div class="yiv9053454032MsoNormal" style="background:white;" id="yui_3_16_0_1_1433637403143_3676"><span style="" id="yui_3_16_0_1_1433637403143_3675"><a rel="nofollow" shape="rect" target="_blank" href="http://www.rcgroups.com/forums/showthread.php?t=952523" id="yui_3_16_0_1_1433637403143_3674">too long battery wires will kill ESC over time: precautions, solutions & workarounds - RC Groups</a></span></div></div><div id="yiv9053454032enhancrCard_0" style="margin-top:3.75pt;margin-bottom:3.75pt;"><table class="yiv9053454032MsoNormalTable" border="0" cellspacing="0" cellpadding="0" width="675" style="width:337.5pt;border-collapse:collapse;" id="yui_3_16_0_1_1433637403143_3441"><tbody id="yui_3_16_0_1_1433637403143_3440"><tr style="height:.75pt;" id="yui_3_16_0_1_1433637403143_3680"><td 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over time: precauti...</span></span></a></span></div><div><div class="yiv9053454032MsoNormal" style="line-height:15.0pt;background:white;"><span style="font-size:10.0pt;">Careful! too long battery wires will kill ESC over time: precautions, solutions & workarounds Electric Plane Talk</span></div></div></div></div></td></tr><tr style="height:3.0pt;"><td colspan="2" rowspan="1" style="background:white;padding:0in 0in 0in 0in;height:3.0pt;"></td></tr><tr><td colspan="1" rowspan="1" style="padding:0in 0in 0in 0in;"><div><div class="yiv9053454032MsoNormal"><span style="font-size:1.0pt;"><a rel="nofollow" shape="rect" target="_blank" href="http://www.rcgroups.com/forums/showthread.php?t=952523"><span class="yiv9053454032link-enhancr-element"><span style="font-size:7.0pt;color:#999999;">View on </span></span><span class="yiv9053454032link-enhancr-view-on-domain"><b><span style="font-size:7.0pt;color:#999999;">www.rcgroups.com</span></b></span></a></span></div></div></td><td colspan="1" 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rowspan="1" width="270" style="border:none;"></td><td colspan="1" rowspan="1" width="217" style="border:none;"></td><td colspan="1" rowspan="1" width="10" style="border:none;"></td><td colspan="1" rowspan="1" width="1" style="border:none;"></td></tr></tbody></table></div><div id="yiv9053454032yui_3_16_0_1_1433621245176_12450"><div class="yiv9053454032MsoNormal" style="background:white;"><span style=""> </span></div></div><div id="yiv9053454032yui_3_16_0_1_1433621245176_12450"><div class="yiv9053454032MsoNormal" style="background:white;"><span style=""> </span></div></div><div class="yiv9053454032MsoNormal" style="background:white;"><span style=""> </span></div><div id="yiv9053454032yui_3_16_0_1_1433621245176_12453"><div id="yiv9053454032yui_3_16_0_1_1433621245176_12452"><div id="yiv9053454032yui_3_16_0_1_1433621245176_12451"><div align="center" class="yiv9053454032MsoNormal" style="text-align:center;background:white;"><span style=""></span><hr align="center" size="1" width="100%"></div><div class="yiv9053454032MsoNormal" style="background:white;"><b id="yiv9053454032yui_3_16_0_1_1433621245176_16535"><span style="font-size:10.0pt;">From:</span></b><span style="font-size:10.0pt;"> hank pronk via Personal_Submersibles <<a rel="nofollow" shape="rect" ymailto="mailto:personal_submersibles@psubs.org" target="_blank" href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>><br clear="none"><b id="yiv9053454032yui_3_16_0_1_1433621245176_16533">To:</b> Personal Submersibles General Discussion <<a rel="nofollow" shape="rect" ymailto="mailto:personal_submersibles@psubs.org" target="_blank" href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>> <br clear="none"><b id="yiv9053454032yui_3_16_0_1_1433621245176_16531">Sent:</b> Sunday, June 7, 2015 12:20 AM<br clear="none"><b id="yiv9053454032yui_3_16_0_1_1433621245176_16528">Subject:</b> Re: [PSUBS-MAILIST] Dive report: Snoopy at Seneca</span><span style=""></span></div></div><div id="yiv9053454032yui_3_16_0_1_1433621245176_12454"><div class="yiv9053454032MsoNormal" style="background:white;"><span style=""><br clear="none">Alec,<br clear="none">I don't know what type of speed controller you are using, but I like and use Curtis golf cart controllers. They are rated for huge amperage and seem bullet proof. I have an extra 36V controller I can send you to try out. They use a 10 OHM potentiometer for the throttle. They also have a battery protection mode, a sort of get home conservation mode. <br clear="none">I labeled the motor in Gamma for a jumper cable, so that I can get home without the controller. As you said it is electronic and it will fail.<br clear="none">If you want the controller send your address of list.<br clear="none">Hank<br clear="none">--------------------------------------------<br clear="none">On Fri, 6/5/15, Alec Smyth via Personal_Submersibles <<a rel="nofollow" shape="rect" id="yiv9053454032yui_3_16_0_1_1433621245176_19349" ymailto="mailto:personal_submersibles@psubs.org" target="_blank" href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>> wrote:<br clear="none"><br clear="none">Subject: [PSUBS-MAILIST] Dive report: Snoopy at Seneca<br clear="none">To: "Personal Submersibles General Discussion" <<a rel="nofollow" shape="rect" id="yiv9053454032yui_3_16_0_1_1433621245176_19348" ymailto="mailto:personal_submersibles@psubs.org" target="_blank" href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>><br clear="none">Received: Friday, June 5, 2015, 6:16 PM<br clear="none"><br clear="none">Hello friends,<br clear="none">I just got back from a dive trip to Seneca with<br clear="none">Dan Lance and thought I'd share how it went. This was<br clear="none">supposed to be a two sub trip with Scott Waters, but<br clear="none">unfortunately a business emergency intervened and it ended<br clear="none">up being just Snoopy.<br clear="none">On the way up the weather was terrible, with<br clear="none">driving rain so heavy I could barely see the lines on the<br clear="none">road. It had been raining heavily for several days<br clear="none">previously. Three times there were emergency announcements<br clear="none">about floods, large hail, and damaging winds, and the closer<br clear="none">I got the harder it rained. The problem with all that rain<br clear="none">is that in your typical lake, the runoff ruins visibility<br clear="none">for weeks. That is what happened last year when Trustworthy<br clear="none">and Snoopy rendezvoused at Summersville Lake, and it looked<br clear="none">very much like this would be a repeat. I'm happy to say<br clear="none">Seneca must be rain-proof, because the deluge only reduced<br clear="none">the visibility in the top fifty feet or so, and even those<br clear="none">were clearer than most lakes.<br clear="none">Here's a few things we learned:<br clear="none">1) Of props and shroudsThe stern<br clear="none">thruster speed control was dead on arrival, although I had<br clear="none">tested it successfully before leaving. I opened up the<br clear="none">enclosure, pressed down all the spade connectors, and found<br clear="none">it now worked - so attributed the issue to road bumps.<br clear="none">However, it died within a minute on the first dive. I had a<br clear="none">spare speed controller, so switched it out. <br clear="none">The replacement died within five minutes on the<br clear="none">second dive. This time at least the cause was obvious, the<br clear="none">prop was jammed by weeds. The current Minnkota props have a<br clear="none">little twist at the end of the blades, and Snoopy's<br clear="none">shroud is made with almost no clearance. The little twist to<br clear="none">the blade tip causes any object coming between prop and<br clear="none">shroud to jam tight, and had already smoked one controller<br clear="none">during the convention in the Keys. I'm going to put the<br clear="none">prop on the lathe and take off the tips to eliminate the<br clear="none">pinching effect and to reduce the amperage draw a little so<br clear="none">the motor goes lighter on the speed controller. By the way,<br clear="none">the speed controller was protected by a fuse rated a little<br clear="none">below the controller spec current draw, so perhaps those<br clear="none">specs are optimistic. Anyway, as a result of the double<br clear="none">failure all of our dives were done on just the side<br clear="none">thrusters because I was out of spare speed controllers.<br clear="none">Lesson for next sub: Design the electrical system with a<br clear="none">controller bypass, so I can operate thrusters with simple<br clear="none">on/off switches if a speed controller fails. They're<br clear="none">electronic, they will fail.<br clear="none">2) Of air bubbles in compensation oil<br clear="none">Snoopy is now routinely diving deep (250 ft) and<br clear="none">this has showed up a puzzling issue with the thrusters. They<br clear="none">were feeble during dives, one died altogether on one dive,<br clear="none">and they kept coming up leaking oil. At first we thought the<br clear="none">seals were failing, perhaps due to some chemical<br clear="none">incompatibility. We found suitable seals at an Amish farm<br clear="none">supply store that sold things like tractor spares (viva<br clear="none">trolling motor simplicity!) When I disconnected the bladder<br clear="none">hose I got quite well sprayed with oil. The motor turned out<br clear="none">to be pressurized. <br clear="none">Previously, I thought if one had a small quantity<br clear="none">of air left in the system it would not be an issue so long<br clear="none">as the compression volume of that air could be handled by<br clear="none">the flexibility of the hose (aka compensation bladder.)<br clear="none">Wrong. I now think what happens is that if the dive exceeds<br clear="none">the pressure rating of the shaft seal and there is a bubble<br clear="none">of any size, you will get water added to the oil and the<br clear="none">bubble stores the pressure. Upon surfacing, the bubble<br clear="none">squeezes oil and water back out until the pressure in the<br clear="none">motor falls to the "cracking pressure" of the<br clear="none">seal. Thus, you get an oil leak even though the seals are<br clear="none">fine. Lesson: Zero tolerance with oil bubbles, even a small<br clear="none">bubble is unacceptable if you are diving deep. I'm going<br clear="none">to put set screws on the motor caps so I can get rid of the<br clear="none">bubbles more easily.<br clear="none">3) An easy way to add<br clear="none">buoyancySnoopy's buoyancy is adjusted by<br clear="none">placing trawl floats in PVC tubes. On one occasion, the<br clear="none">oncoming passenger's weight required the addition of<br clear="none">just one float (i.e. the new guy weighed seven pounds more<br clear="none">than the one getting off). The support diver wasn't<br clear="none">suited up and the water was 42 degrees, so I just pushed a<br clear="none">float under the lip of the forward MBT. It worked like a<br clear="none">charm, and the float even stayed in place throughout the tow<br clear="none">back to the ramp. Lesson: You can easily add a few floats<br clear="none">for buoyancy on a standard K sub, no special tubes<br clear="none">required.<br clear="none">Most of our dives were along a very steep<br clear="none">incline, not quite a wall but more like a series of ledges<br clear="none">and very steep slopes. Between the steep terrain and the<br clear="none">good visibility, the K250 dome for once offered a really<br clear="none">good view. We typically made our way down the slopes using<br clear="none">very slightly negative buoyancy, trailing the back corner of<br clear="none">a skid on the slope. Looking aft, you could see a zigzagging<br clear="none">trail of silt hanging motionless in the water and tracing<br clear="none">our path. The sub compresses with depth, so slightly<br clear="none">positive buoyancy at the surface turned into slightly<br clear="none">negative at depth, but we're speaking of just a couple<br clear="none">of pounds and not anything that caused difficulty. In fact<br clear="none">at one point we stopped dead in the water four or five feet<br clear="none">above a flat bottom for about five minutes, just waiting for<br clear="none">a pre-arranged touch-point call on comms. The sub didn't<br clear="none">rise or sink an inch, she just hung there completely<br clear="none">immobile for five minutes. At about 140 feet the visibility<br clear="none">would improve significantly, and the water changed from<br clear="none">green to blue. It looked like ocean instead of lake water.<br clear="none">I'll post a video, but that'll take a few days to<br clear="none">put together. The only "incidents" we had were a<br clear="none">cold bath we took when we closed the hatch over a corner of<br clear="none">the crew's shirt, and when we got hooked on a log at 220<br clear="none">feet - fortunately reversing got us right off<br clear="none">it.<br clear="none"><br clear="none">Best,<br clear="none">Alec <br clear="none"><br clear="none"><br clear="none"><br clear="none"><br clear="none"><br clear="none">-----Inline Attachment Follows-----<br clear="none"><br clear="none">_______________________________________________<br clear="none">Personal_Submersibles mailing list<br clear="none"><a rel="nofollow" shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org" target="_blank" href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><br clear="none"><a rel="nofollow" shape="rect" target="_blank" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a></span></div><div><div class="yiv9053454032MsoNormal" style="margin-bottom:12.0pt;background:white;"><span style=""> </span></div></div><div id="yiv9053454032yqtfd66451"><div class="yiv9053454032MsoNormal" style="background:white;"><span style=""><br clear="none"><br clear="none"><br clear="none">_______________________________________________<br clear="none">Personal_Submersibles mailing list<br clear="none"><a rel="nofollow" shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org" target="_blank" href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><br clear="none"><a rel="nofollow" shape="rect" target="_blank" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a></span></div></div><div class="yiv9053454032MsoNormal" style="margin-bottom:12.0pt;background:white;"><span style=""> </span></div></div></div></div></div></div></div></div></div><br><div class="yqt2172010875" id="yqt07093">_______________________________________________<br clear="none">Personal_Submersibles mailing list<br clear="none"><a shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org" href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><br clear="none"><a shape="rect" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles" target="_blank">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br clear="none"></div><br><br></div> </div> </div> </div></body></html>