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Unread 13-01-2009, 14:48
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Tristan Lall Tristan Lall is offline
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Re: paper: 2009 Motor Data

The RS-545 data there is for an older motor supplied by Mabuchi. The 2009 RS-545 motor is similar-looking, but not manufactured by Mabuchi, and has different specifications.

Also, I was playing with the spreadsheet, and noticed that the "At max. efficiency", "Normal rated load", and "At max. power" rows don't do anything, and actually only contain information for one particular motor.

And I'm not exactly sure what's going on here, because BaneBots lists Kv = 1400 rev/(min·V), which works out to Ke = 0.00682 V·s/rad. The spreadsheet calculates Kv = 0.006529 V·s/rad. Similarly, BaneBots quotes Kt = 0.0079 N·m/A, while the spreadsheet returns Kt = 0.00581 N·m/A. (These constants affect pretty much everything.) I had a quick look at Mark's math, and it looks right, so I'd have to guess that BaneBots may not have the correct values for something. (But are their given speeds, currents, etc. correct, or their constants?)
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