ZeeBeeMus
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Sorry if this is covered elsewhere, but for people making packs using the sequre sw1 and maybe it also applies to malectrics, what should the max car battery CCA be? Sequre says 400-800 CCA, but Iām concerned if I use a 760 CCA that it could potentially output more and damage the welderā¦ Iāve seen more than one post about this with the SW1. Iām looking at getting an agm interstate battery and my options are 650 or 760ā¦ Will the 650 be too little for .2 nickel?
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The better question is will the sequre be too little for 0.2, Iāve heard that they really only do consistent stuff at 0.15
Hmm, I thought it was basically a malectrics cloneā¦ Maybe I donāt know what I am looking at either, itās possibleā¦ But Ive seen a lot reviews from all over demonstrating it and it seems to do well with .2
Motors do not āpullā current. Motors are dumb, inert hunks of copper, iron and rare earth metals. They have no way to āpullā. Without an external regulating/controlling device, our motors will basically act like a dead short across whatever battery is applied to them, drawing hundreds of amps for a very short period of time before either destroying themselves or the battery.
The motor controller is the only āsmartā piece in the chain - it draws power from the battery, and sends it to the motor(s). The motor gets no say in the matter. Neither does the battery.
Motor current also is not the same as battery current. The ESC effectively acts like a DC-DC converter, stepping down the battery voltage while at the same time stepping up the motor current (because P=IV) . It is entirely reasonable for the ESC to be drawing 10 amps from the battery while supplying 50 amps to each motor.
Battery current and motor current both have effects on how the board feels and performs, but they are not explicitly linked with each other.
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*DC-AC converter
3 phase motors run on AC. Just nitpicking though, good explanation. 
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So then why are our motors called dc motors? 
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Nope, itās pretty much junk
There was a time where sequre was soambotting the forum. Not fun.
Because You supply them with DC I believe. Also Iām not exactly sure its proper to call what the motor controller puts out AC or not. Itās essentially pulsed DC power, which in practice is a bit different from what most ac motors run on.
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The wave form on the phase wire does oscillate from negative to positive tho right? I feel like technically thatās AC even if it were a square wave? is that wrong?
( i model foc as a series of dc pulses of varying length, approximating a sign wave )
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yeah that is true, maybe it does count as AC. I guess what i really mean is that for most āACā motors, the wave form is consistent, varying primarily in frequency, whereas in our motors frequency is fixed and duty cycle changes.
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Ughh, shitā¦
Another clue would be that our āESCsā are officially known as āInvertersā, which is by definition a device that converts DC to AC.
A power inverter, or inverter, is an electronic device or circuitry that converts DC to AC. The input voltage, output voltage and frequency, and overall power handling depend on the design of the specific device or circuitry. The inverter does not produce any power; the power is provided by the DC source.
https://www.sciencedirect.com/topics/engineering/power-inverter
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Iāve never seen someone call them this Maybe its just oversimplification?
BLDC motorsā¦ āBrushLessDirectCurrentā is my understanding what BLDC means.
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Kind of a misleading nameā¦ EC-motor would be a more correct term I think.
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fair. iām just pointing out you could see how people saying BLDC motor could be seen as people calling them DC motors, and iām sure youāve heard people call them BLDC.
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Yeah I get that you could short that to DC-motor, but it sounds so wrong.
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This page for example, suggests a PMSM motor is āACā and a BLDC is DCā¦
Difference between BLDC Motor and PMSM Motor.
soā¦ i definitely have a hard time with the verbiage spread out across the net.
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