Hi ... Im new to VESC. I typed up a long story only to lose it before posting so Im likely to be a bit short here.
I have a recently purchased VESC 6.6 from FlipSky that appears to be limited on eRPM to 40600 even with lots of changes.
The motors are 6384. I have a large bank of 96 BAE A123 batteries. It shows 39.4 volts in the VESC tool.
I bought about everything from FlipSky new. Im running a VX1v6 remote.
The VESC tool was downloaded just a week or so ago. It say 3.00 on the filename.
Of course it gives me a message when launched that my firmware is out of date.
Also when I went thru the Motor setup it said it was outdated and when I tried to setup the controller it flat said the firmware was too old and would not go thru the setup.
I dont mind updating the firmware but Im kinda thinking there is no newer version and that it shouldnt matter that much. Happy to be wrong and that is likely my next step to check into.
The VESC tool says its FW 5.1 and HW 60
Running it with no load it gets up 40600 real quick and abruptly flats at 40600 looking like its something digital.
The Duty Cycle is 95% or so... the throttle is not completely open but moving the action does not change the duty cycle
I dont push it completely to wide open as it seems that something odd happens up there.
The default ERPM is 100000. I can put it at 150000 and the Limit Start from 80 up to 95% and it still stops at 40600
If I run the ERPM limit down to 30000 it will limit it at 30000
I thought it might be current limited and so I looked up the control for current at it set 75A or so ... all default. no changes here that I know of.
Its only running about 2A when it hit this limit of whatever sorts it is.
Greatly appreciate any help.
Thanks, Dan...
ERPM is pole pairs * kv * voltage. So if its at 95% duty cycle you are at the max speed the motor will go at that voltage.
If you have set it up as current control with the remote then it will go to max speed if there is no load on the motor.
Hi TechAUmNu... Thanks for the response. So would you say that a 192 kV motor with 40V should see 7680 Rpm? Thanks, Dan...
Im seeing 5840 Rpm... Which works out excellent in agreement with 41600 erpm/ 7 poles = 5942 rpm
Im only at 39.4 V so a bit shy of 40. Also only at 95% Duty Cycle. Taking all this into account it hint that I have about 81% 'Efficiency' using the esk8 calculator.
I suppose I would say Im fairly surprised the 'efficiency' would be this low. Im not even sure whether to call it efficiency or slip or marketing fudge.
http://calc.esk8.it/
Does anybody know the physics behind the 'efficiency'.
Well fairly disappointing but I suppose good to know. Im also surprised how the rpm can go vertical up to what looks more like a limit and then abruptly run flat.
Thanks if anybody can shed light on the trivia of this.
Thanks, Dan...
My 270kv motors from flipsky are only about 220kv, so its more likely they just spec the kv wrong.