So then for my use case, with a setup that doesn’t need 100V support the D75 would actually be able to push more power due to the higher continuous current output potential? Interesting.
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Yeah, resistance makes stuff go hot once it conducts current. MOSFETs only can get so hot before calling it quits, so resistance dictates how much current they can conduct before they heat up too much.
What really gets you going are watts, so just multiply current by voltage and you’ll get a theoretical power figure.
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Yeah, and even if you’re running close to the total peak wattage output you’re gonna warm up fast, having an external heatsink will make it last longer though
But it is interesting that you could make the decision to get a lower potential one for more amps haha
I wonder how the pricing structure will be
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But at any given motor rpm (assuming we use the same motors with the same kv and such), the power is just based off of amperage output to the motor as the voltage to the motor is the same no? Like if i had say, a 12S8P setup or something nutty, the D75 would be able to push 120A off the line, versus the D100 only being able to push 100A off the line. Even if i gave the D100 setup a higher voltage battery like a 16S or whatnot, off the line it’s still going to produce less power than the D75, as that higher voltage only gets utilized near the top end right?
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As for overheating, i’m trying to work around this as much as possible, bought some radium 6485 motors to deal with heat soak so hopefully those won’t be my thermal constraint. For the ESC i’m probably going to do something crazy like watercool it haha.
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Lol I don’t think you’ll need to watercool, usually an air facing heatsink is plenty. Is this a street build or MTB?
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High end street build haha. I’m dealing with hot texas weather and i ride pretty aggressively, plus i’m trying to make it a showcase build. None of my decisions are strictly necessary, but hey it’ll be neat once i’m finally done living off of ramen to buy parts!
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That makes sense! High ambient heat overheats things real quick haha
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Yep haha, i’ve got a Zeus Pro and while it’s only 13S4P, probably pushing under 70A total from the battery, the ESC can get pretty toasty after a hard session already. And i’m planning on eventually going to something like 16S6P or 18S5P of P42A cells, trying to max out how much power i can put down on two motors. That’s why i’m trying to figure out if the D75 would be better suited with it’s higher continuous amperage than the D100.
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Motors have a largely fixed resistance that is presented with voltage from the VESC according to (battery voltage)*(duty cycle %). This is a simplistic way how to think about it, but it’s pretty close to reality.
All of these VESCs have pretty similar power figures - 9600W@60v, 9000W@75V and 10000W@100V with the 100V setup probably having the highest chance to achieve max power due to less resistive losses. You should be happy with either choice unless you decide to run the 100V version at 12s at which case you’re looking at 4400W at nominal voltage.
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Well, what i’m asking about is more of what’s the actual power curve look like. Peak power figures are great and all, but more realistically i’m going to be using the low end and mid end power. Like lets say i’m comparing a 12S8P on the D60 versus a 16S6P on the D75, the batteries are the same number of cells and capable of the same peak battery wattage so that’s irrelevant. Lets say they’re both geared to the same top end, off the line the 12S8P D60 setup should be able to supply more motor power and launch harder due to the higher amperage spec right? It’d only be near top end where the D75 setup is actually making use of a higher voltage to the motors where it climbs up to it’s peak wattage.
To make it a bit more clear, while yes it’s true that at peak voltage and top speed a D60 would be at 60V, 160A (9600W), D75 would be at 75V, 120A (9000W), D100 would be at 100V, 100A (10000W), the situation i’m asking about is more asking about what the actual effective power curve is across the range of motor rpm’s for a given setup
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Older escs don’t have it. I just had to reflashed my unity and it doesn’t have it. But by default it turns it on. The info button says it should affect it if it’s on but I don’t think it does. Seemed to have different values when I ran detection.
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Weird weird, who knows. Guess it’s a non-issue? Is it only required for Silent HFI then?
I believe so. That’s why frank is always about if hardware allows it’s.
Dependent on all the other manufacturers including the similar spec components
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Motors dont really care about anything other than watts… Even though the higher voltage setups cant push as many amps, because lower kv motors are wound different those amps become more effective at producing torque at the cost of rpm, which is then madeup by the higher voltage.
Watts is all you need to worry about. Hence why I’m excited for the D60. Less battery series connections and a cheaper/smaller BMS, standard chargers, with the same performance as a 100V setup sounds good to me.
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Really? That’s interesting, i’d have thought the model with lower amperage would perform noticeably worse as wattage is just voltage*amperage.
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In this case the higher voltage controllers have lower current ratings so overall watts is similar between the 3
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Gonna lose my mind with this ESC y’all 
So had one blow up, and this one is only detecting one side in VESC tool. Ram motor detection and only one side spins. Has anybody had this issue before and resolved it?
I had two of the Makerx Hi100 which are the previous 75V based on 75/300 makerx controller and they were going great for ages on 12S. However when I went to 300kv motors although they detected fine, when I was spinning the motors up on the bench one of the mosfets just exploded. And after all the ubox fails it makes me think 75/300 hardware is a bit unstable compared to vesc 6 which seems to be pretty bulletproof on hardware designs that have been successful like the DV6. Thats just my perception
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How would I check to see if that happened?
Not sure, It was riding fine. Then one of my sensors stopped working so I ran motor detection again, and suddenly stopped showing one side of the ESC. Can’t get it to show up.