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<div>Alan,</div><div>Pretty high tech operation you have going there. I am curious how many wires it takes to run these? </div><div>Hank</div><div><br></div>
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On Friday, September 7, 2018, 4:57:18 AM MDT, Alan via Personal_Submersibles <personal_submersibles@psubs.org> wrote:
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<div><div dir="ltr">Testing my new motors. I did an amp draw comparison between running them in air<br></div><div dir="ltr">& in a low viscosity silicone oil. I ran them at varying speeds from 150 to 2,400 rpm,<br></div><div dir="ltr">with no load. The speed controller is connected to the computer & I can monitor <br></div><div dir="ltr">the temperature of the motor & esc as well as Watts, Amps, rpm etc.<br></div><div dir="ltr">In air I was only drawing around .2 Amps for the whole range.<br></div><div dir="ltr">In oil strangely enough I was drawing less amps to begin with but this evened up at around 800 rpm. Bearings must have liked the oil. After this the Amp draw went up to 1 Amp at 2,400 rpm. There are veins at one end of the motor for cooling & these agitated the oil quite a bit as the rpm advanced. These are good for circulating the oil for much<br></div><div dir="ltr">needed cooling but were a bit too aggressive. If it weren't for the veins there probably<br></div><div dir="ltr">would be very little difference in Amp draw. I am going to grind off some of these veins<br></div><div dir="ltr">& see how it goes. The oil had a massive advantage in cooling the motor but it looks<br></div><div dir="ltr">like I can only run these motors continually at about 25 Amps off 48V. On higher Amp draws up to 40 Amps the temperature was climbing at nearly 1C every second untill it<br></div><div dir="ltr">hit 80C, at which stage the systems over temperature protection cut back the Amps.<br></div><div dir="ltr">Great to be able to dial in loads & speed on the laptop & get accurate motor performance data back. The screen shot is of the Vesc tool that is free! I know the Vesc<br></div><div dir="ltr">motor controller runs brushed motors but I am not sure what diagnostics you could<br></div><div dir="ltr">use on them.<br></div><div dir="ltr">Cheers Alan</div><br>_______________________________________________<br>Personal_Submersibles mailing list<br><a ymailto="mailto:Personal_Submersibles@psubs.org" href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><br><a href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles" target="_blank">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br></div>
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