What is the kv rating

[a.flynn]

I now need to get the EDF for my boat build project but what is the kv rating or number and what should I go for?  I've seen values ranging from 800 kv up to 1600+ kv.

[cybernut]

The kv number is how many rpm the motor will do per minute per volt.  So if the kv value is say 1000 and the battery is 10 volts, then the motor will do 10,000 rpm.

[A.Jenery]

I now need to get the EDF for my boat build project but what is the kv rating or number and what should I go for?  I've seen values ranging from 800 kv up to 1600+ kv.

I'm no expert   , but as I understand it a lower kv motor has a higher number of winds of thinner wire, higher kv has fewer winds of thicker wire.  So the former will carry more volts and draw fewer amps so have better torque, the latter will carry less volts and draw more amps from the battery but have less torque.

[ATH019]

Interesting topic here and agree with the answers so far!  Other numbers to bare in mind are one's like 4832 which refers to the length and diameter of the motor, so 48mm and 32mm respectively.


Global Moderator

[blag-it Admin]

Good day everyone!  Also make sure that the brushless motor is an inrunner not an outrunner and that the esc is brushless at at least 80 amps.


Admin

[ATH019]

Good day everyone!  Also make sure that the brushless motor is an inrunner not an outrunner and that the esc is brushless at at least 80 amps.


Admin

Yes, very good points!  Especially with the ESC which must be brushless.



Global Moderator

[a.flynn]

Thanks to both. Will definitely make sure the esc is brushless!  Already have the edf unit now and the motor is an inrunner.

[a.flynn]

Slightly off-topic here but still to do with this build.  I still haven't been able to get certain parts for ages due to shops being closed because of this covid-19 stuff.