Mamba Max vs Quark Observations - RC-Monster Forums

jhautz · 01.03.2007, 08:06 PM

Brian,

Really interesting find there... I'm not sure Im underatanding exactly why a 4 pole motor makes a difference over the 2 pole though. Whats your thinking on that???

I can see how a locked rotor can cause a big heat issue for the MM if the motor is too large. though. Probably why I had mine fail whill cogging on a large motor. It cogged so bad it acted like a locked rotor and just pulled to many amps.

danverz · 01.03.2007, 08:09 PM

Brian, I am experiencing the same behaviour.

Ciao,
Daniele

BrianG · 01.03.2007, 08:41 PM

Well, it seems people running more than 2 poles (like the Neu) seem to have more problems than people running 2 polers...

jhautz · 01.03.2007, 08:44 PM

Oh.. I tought that there was some electrical reason for the difference. Being the electrical guy around here and all.

See what you did... Now not only am I getting used to long fact filled explanations, I'm starting to expect them. :D

BrianG · 01.03.2007, 09:14 PM

@jhautz: Lol. This time the answer was simple. :)

@crazyjr: I really don't know. That might be part of it.

It's like the MM ESC is saying: "Hmm, the rotor didn't turn. I'll just give it more power! Hey, it still didn't turn?! Well, I'll give it all I have!". And if the rotor still doesn't turn, the ESC heats up like crazy and possibly blows.

Don't forget, when a motor's rotor isn't turning, the only thing limiting current is the DC resistance of the coils, which is quite low. A rotor turning through the magnetic field generates back EMF in the coils, which increases the resistance (actually "impedance" when you start getting into AC).