<html><head></head><body><p dir="ltr">Brian, if you are talking about compensating a volume with direct exposure to motor windings, or indeed any electrical or electronic equipment, you MUST use a high dielectric oil intended for such purposes. Pure mineral oil will fit the bill, but almost all of the oil companies sell dielectric oil products intended specifically for this purpose (i.e. as transformer oils).</p>
<p dir="ltr">For other volumes which don't put electrical gear at risk, you have other options. The commercial vehicles I have worked on used at most two different oils: one hydraulic for power transmission (thrusters and actuators), and one dielectric for compensating wiring, light ballasts, and electrical enclosures.</p>
<p dir="ltr">To minimize internal resistance on a motor, you ideally want a very low viscosity oil, which may be at odds with the best available dielectric properties. I'd be inclined to accept a bit of extra drag if it means not burning out a motor, but of course, higher viscosity will increase the motor load, so there is a tradeoff.</p>
<p dir="ltr">Sean<br>
</p>
<br><br><div class="gmail_quote">On November 19, 2016 12:49:22 PM MST, Brian Cox via Personal_Submersibles <personal_submersibles@psubs.org> wrote:<blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
<div style="font-family:Arial, sans-serif; font-size:10pt;"><div>Hi All,</div><div> I know this subject has been thoroughly discussed but what would be a good oil to put in my motor pod? Is there something about transmission fluid that would be bad? What about hydraulic fluid? or a light oil like a 0 - 20 weight?</div><div> </div><div>Thanks,</div><div> </div><div> </div><div>Brian</div><div> </div></div>
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