Hall wire/cable swap question

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E-HP   100 MW

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Hall wire/cable swap question

Post by E-HP » Jun 15 2021 9:33pm

I was about to order more 10 gauge wire to modify my battery harness to add another lipo pack, when I saw a deal with a set of 5 wires, 5 ft each (black, red, blue, yellow, white) and thought that maybe it's time to upgrade part of my phase wires too. The cheap hub came with pretty thin wires, and questionable whether they have any copper in them. I frequently touch the motor after a steep hill climb, but never the wires, but I'm guessing they get warm.

Anyway, if I upgrade the phases, then I need a solution for the halls. I looked for 5 or 6 conductor cables, but don't want to buy 50 ft or the larger lengths they sell. I'm thinking of using a CAT5 patch cable, which has 4 sets of twisted pairs. My thinking is to used 3 of the twisted pairs for each hall, and the third to carry the 5V and ground. I also thought of using only one conductor of the 3 twisted pairs, and run ground through the other 3 wire from those pairs, and 5V through the last set of twisted pairs. Not sure if that would help or hinder potential electrical interference.

Any opinions or experience, or alternate methods for running the halls would be greatly appreciated. I'm cheap, so the patch cable seemed like a cheap solution. Thanks ahead of time. :o

PS. After the battery harness, I'm thinking of upgrading the wires from my triangle pack, that runs in series with the lipos. They are the weak link, since they appear to be 12 gauge, and the rest of my harnesses are 10 gauge, I'll need to open the pack to access the BMS and solder on the new conductors. Any precautions I should take, on top of just being super careful?

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dogman dan   100 GW

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Re: Hall wire/cable swap question

Post by dogman dan » Jun 16 2021 5:43am

No particular reason to upgrade the halls. They just carry a low amps signal. The phases you can cut a few inches out from the hub, and the thicker wires will start heat sinking some of the warmth from the remaining few inches of phase wire. And that short, less resistance in the original phases.

Any much more than that really needed, then you may be pushing too much phase power into the motors winding to make any sense. I mean like, say you have 500w rated motor, 4000w + is just way more than the winding can do anything with but make heat.

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E-HP   100 MW

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Re: Hall wire/cable swap question

Post by E-HP » Jun 19 2021 11:12am

dogman dan wrote:
Jun 16 2021 5:43am
No particular reason to upgrade the halls. They just carry a low amps signal. The phases you can cut a few inches out from the hub, and the thicker wires will start heat sinking some of the warmth from the remaining few inches of phase wire. And that short, less resistance in the original phases.
I ran my motor hard yesterday, to the point where it was too hot to touch; way hotter than it's ever been. This time, when I jumped off to feel it, I also felt the phase wires and they were normal. Near the motor, they were warmer, which seems like the heat sinking you mentioned. Similarly, the axle was also warm.

My conclusion is that the motor will melt before the phase wires will, so not as much of a reason to upgrade them for now. Plus, I actually found just enough 10AWG wire to finish my harness.

My other conclusion is that the Statorade is working as it should, transferring the heat to the housing in order to dissipate the internal heat. When I first added it, I followed the directions from the website:
"...on most hub motors the full effect is reached with somewhere between 5-8 mL at modest RPMs, and 8-12mL for fast RPMs. If more Statorade is added beyond this, then there is almost no change in the heat flow but you will start getting increasing viscous fluid drag."
so I added 8ml, thinking that was my particular case (modest RPMs), and not wanted the fluid drag. Now I'm thinking I should just add the rest (bought the 10mm syringe). How much are most people running in a (MXUS) 9C clone??

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