When I asked, I was referring to sensored motors. APS said, "All the brushless motors can work under water".
I dunno. Hard to believe, isn’t it?
I’d love someone with some expertise on the subject to chime in on this.
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I’ll document the before and after charge status for now.
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@brown5tick @sesat From a pure mechanics standpoint, since a brushless motor is just magnets and coils with no switching or other exposed electrical stuff going on, yes, they are all waterproof in that they won’t immediately short out or break the moment they enter water.
That does not mean that all brushless motors are designed and hardened against operating underwater. The bearings, the magnets, the steel stator laminations, the flux ring and shaft, and the steel screws, all have the potential to corrode over time, as will the hall sensor PCB and the phase wire connections if they’re not coated and sealed properly.
So yes, in theory, all brushless motors are waterproof, in that there’s no internal brushes or commutators, but most brushless motors will only survive that treatment a very limited number of times, unless for example, you wash and then bake your motors after every dunking to remove any salts, and then remove all traces of water before it can cause issues.
Where the phase wires solder to the magnet wires need be well sealed. Sensors are another issue beyond
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If you are not using sensors, then BLDC motors should work, albeit not as well, while wet. I’m not sure if submersing is a great idea, but once taken out they should work despite accelerated bearing wear.
If you’re using sensors, a tiny bit of water can ruin it…
Like @hummieee said, it’s still a good idea to seal where the phase wires terminate to the windings. Though it’s not 100% necessary if they won’t touch one another.
if a phase does short you’ll find out pretty quickly because the motor will lock up almost instantly
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Any idea why I stop going up a 10% hill? I start up the hill, slow down, and within 15 feet stop completely. I had thought it was voltage sag, but I am not seeing it in the data. I have a single drive 6374 with 36:16 gearing, 90mm ABEC, and a 10s3p 30q pack. Rider and board are about 180lbs.
@Tbone which part of the graph is the hill, what’s your kv, whats your motor and battery current limit settings?
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The hill is at the very end of the graph where the speed goes to zero. Elevation is on the right axis, everything else is on the left. Motor kV is 190 (TB motor).
Battery_Max=45.0
Battery_Min=-12.0
Cutoff_Start=34.0
Cutoff_End=32.0
Temp_Start=85.0
Temp_End=100.0
Sorry, missed that on my copy/paste. Motor current is set to 60 / -60
@Tbone that’s odd because it appears on the hill the motor current was only 30-35a, I assume you were using full throttle?
Full throttle for sure
maybe the esc was getting hot from that long downhill section where you were getting 50a+ regen motor current and so it did some thermal throttling of your motor current as a form of self preservation? i’m trying to understand why at full throttle at low speeds you’d only get 35a motor current if your motor current limit is set to 60a
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That depends on the deck too and your riding style.
I had a $35 moose deck from amazon snap right behind the front truck and dump me on my Face. I had made no modifications to the deck. That deck was just plywood. The replacement, a proper wood/fiberglass board from sector nine. Then I stripped it and layered another 3mm of fiberglass to reinforce it especially in the area between my feet and the truck on either end.
Your decks construction should be considered. You’ve described a hole location under your foot and potentially the worst place for one. Between your foot and the truck would be worse.
Ideally, a flatter battery pack layout could maintain the ground clearance you want to maintain. But I don’t think it’s worth it to route the deck for 3/8”. Whatever that’s for, put it else where and deal with the ground clearance loss. You’ve already got big wheels 
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What remote are you using, and did you set it up so that a full trigger pull is 100% in the ESC Tool?
If I’m reading it correctly, it looks like your battery current is only hitting 12A or so
i’d only expect him to reach his battery current limit while accelerating full throttle close to top speed
(at lower speeds it takes less battery current to produce constant motor current)
so accelerating full throttle while at low speeds he should get the full 60a motor current using much less than 45a battery current
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^as I suspected, with only 32a motor current, 90mm tire, single drive, 190kv, 36v battery and 36:16 gearing & 200lbs, the vehicle thrust is insufficient for acceleration on a 10% slope
(red line - vehicle thrust is below green line - 10% slope + wind drag force across the whole chart)
@Tbone if you can figure out how to make your esc provide 60a motor current you should be able to make it up that hill, because you will have nearly twice as much available vehicle thrust
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Problem is I just paid out for this battery, unless you have a brand new 12s3p 30Q that’s less than 40mm tall you can trade I don’t have many options
It’s a decent quality deck and I’m like 130lbs soaking wet so it might live?
If I was better at pack building I might separate the BMS but I don’t trust myself
^ @Tbone if you were actually hitting those current limits at full throttle (60a motor and 45a battery), the graph would look like this, which shows you would have sufficient thrust to climb a 10% hill at up to 25mph
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