i have 10s3p battery. how do i know what Ah it is?
Nah I just copped the deck for like a hundred cuz I like coffin shaped things and was like woah is that a bms? When it arrived.
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what cell u got inside?
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If you bought it pre-made look for what type of cells they advertise or ask the person who made it. If you still can’t find out, you could carefully open the wrap and look at the cells but it’s not a good idea unless you definitely know what you’re doing. Once you know the cells:
Each cell has an Ah rating. Multiply that by 3 because you have 3p. If it’s made of Samsung 30Q cells for example, it has 3000mAh per cell, so 9000mAh in the pack. 9Ah.
You likely have between 7.5 - 10.5Ah if they’re decent name brand standard size (18650) cells. Up to ~14.5 name brand larger cells (21700), as low as ~4Ah if it’s cheap chinese stuff or fakes.
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Thanks! Also I have another noob question. My vx1 receiver wont start, vant figure out were the wires should connect! 20210618_163222|281x500
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I have seen people have som funny things next to their nicknames. How do i go about to get this? 
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You can only get those from a higher up adding it to your profile
Hard to get them anymore since the mod drama that happened, only the site owner and one other person have profile editing permission now
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Just have to get noticed then. 
Alright installing stormcore 60d+. So how much does the orientation of my bullet connectors on phase wires matter? I believe my motors have the female bullet so the VESC side will have the male bullet
I personally don’t like having male ones on the VESC side because it’s very easy to short 2 phases together by accident. Still very possible to do it with the female ones (why I prefer MR60s because they’re fixed in place) so it’s important to adequately insulate them, but less easy. Probably the correct answer is “it doesn’t matter the orientation because you’re going to be good and take extra care either way”, but stuff happens so…
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I’m kinda confused about the Xeniths specs; it had a max cts current of 160a, but it comes with 12awg wire and an xt60? I realize you’ll probably like never pull 160a, but could any one clarify how theses numbers work?
yeah sounds about right. Mine are definitely good and insulated.
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To be fair I think this means 160A combined motor current so it’s split between two sets of conductors and connectors for 80A each. That is going through MR60s, basically xt60s, so it’s still IMO not ideal but also not terrible and by my preference better than using 4/5.5mm bullets because of
I can’t seem to find claims for battery current, and for those I think you’re right that 12AWG and XT60 isn’t right. Especially XT60, because at least for the MRs you can’t get bigger combined 3-pin ones, whereas for the battery XT90 exists and is not a big ccost difference.
Maybe they’re relying on anyone who’s gonna really floor these things being willing to change connectors, but I would prefer 10AWG for at least some of the wires. Usual caveats: I haven’t done mountains of research for thie comment so pls correct me if I’m wrong
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Yeah, I wrote about how dumb that honestly is. It’s like you have to either get a coma or be highly injured that they still can’t do anything for you. You’re lucky to even get the license plate before you end up pretty badly.
Max total in pairs is 160A, it means both can handle 80A each side. Which is why it says motor amp 80. Burst current is 150A each side, which is what the absolute max of the esc states (150A both side).
12awg can handle 80 amps just fine. MR60/XT60 can also handle those amps just fine as well (if you have a more powerful battery, I’m not 100% on that. It’s better to maybe make it 10awg and XT90). They’re not gonna make it if it’s over 120A since I believe that’s the limiting point (so I’ve heard. I believe it can do over 160A before melting).
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Ahh I see, that clears things up; thanks guys
Has anyone replaced the battery wires and connector (on the esc) with something beefier like 10awg and an xt90? I may or may not do it, in addition to adding a heatsink at that point if i may pull that many amps.
I’m might not immediately need to, but if I get pneumatic wheels I suspect I may need something that can handle more current.
Yeah it’s useful to have guidelines like this, but it basically comes down to duration. This is not necessarily directed at you but it’s a noob thread so could be useful, apologies if it’s condescending
- All current carriers have a resistance R
- Heat energy per second (measured in terms of power in watts because it is energy per second) generated from current through a resistor is P=(I)²x(R )
- Heat dispersed from a body (eg a wire) is a function of its area (large areas dissipate more heat per second), and the material (some materials transfer heat well, some insulate well), along with other factors.
- If the energy added from resistive heat exceeds energy dissipated, energy is added
- Large energy per second for a long time results in a lot of heat energy, which depending on the material results in a high temperature. Some materials take a lot of energy to heat up, others don’t.
- After a certain temperature a material melts or is otherwise unhappy
- If you put very high currents through a small conductor it will heat up very quickly, but as long as it doesn’t accumulate enough heat to melt it’s probably fine.
- You can put all of this together with experimental measurements to get to guidelines for currents that are safe to run forever if the wire can expel the heat, safe to run for a while if the wire is just about adding heat to itself but not very quickly, and not safe to run at all because it’s roughly impossible to get rid of that heat
The current that will almost instantly melt a wire is referred to as the fusing current and for 12AWG it’s >200A. Really does not mean it’s a good idea. Any current carrying guidelines make assumptions about the length of time, the length of wire (long wire = big total resistance), and the environmental conditions like airflow, insulation, and ambient temperature. If you read a chart for house wiring where there are long runs, no ariflow, 24/7 operation, and flammable material around, they may be a lot more conservative than for an eskate.
Edit: even if you don’t blow up a conductor doesn’t mean it’s good. Power turned into heat is power not sent to the wheels. This loss of power is where voltage sag comes from, why you lose some torque under rough conditions, and the heat can have other big negative impacts like increasing wear on battery cells or MOSFETs in the ESC
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I got an uh interesting one upon request
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This is great to have and be understood. If this was used, there would be less issues when it comes to a lot of things regarding esk8 (and surprisingly other stuff as well). I guess it all comes down to what you can know and what you can apply.
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