Ok, I got a controller, now for a motor...

[Karadjas]

I picked up a Graupner Genius 30 (not 80, although that was what I ordered) about a week ago, and I'm waiting for the motors to arrive at the LHS.

I'm a bit confused though. The Genius 30 has a 30amp constant current draw limit, but I didn't find any amp ratings on any BL motor anywhere. Tower, Hacker website,Graupner website,Novak website... Nothing.

Is there a 'conversion scale' so to speak, as in 5.5 turns draw this much, 8.5 draw this much? I don't really think this is the case, I can't see a Novak drawing the same as a Hacker.

I'd love a Graupner Evo2 5.5t motor, but I do not know if it will work.

Any help?

Thank you,
Michael Karadjas

[tcolesen]

Motors are often given amp ratings from the factory, but in reality these amp ratings mean nothing. Things that can affect the number of amps a motor will pull include:
-Gearing
-Battery voltage (higher the voltage, the more amps that are pulled unless gearing is reduced)
-Tire size (larger they are the more amps that are pulled)
-Amount of traction (more traction means more amps pulled)
-Driving style
-Hard acceleration/low-speed driving/high-speed driving

As you can see, it would be virtually impossible to put an amp rating on a motor. This is why many companies don't do it. What you should know is that motors relative to each other will pull different amounts of amps, ie a 5.5 will pull more than a 6.5.
The Novak motors can draw just as many amps as a Hacker, or more. The amount of torque a brushless motor produces is proportional to the number of amps used. The only things limiting how many amps a motor can pull are the voltage drop of the battery and the internal resistance of a motor (from its windings).

You did not specify which vehicle type you are using, but I would guess that you are using a 1/10 scale. If this is the case, then you are going to need a controller with a higher rating than 30amps, unless you use high voltage. I will admit that I don't know much about the Graupner controllers, but it would probably be best to wait for the Genius 80.

[aqualato1]

The Velociti 5.5 pulls about 60 amps constant and can peak like 110 amps and sometimes more.

As for the controller, I would not use the Genius 30 because many brushless motors are asking for amps to which the 30 can't handle and thus it'll be damaged. So I sugest getting rid of the 30 (sell/trade) and get the Genius 80 or some other like it.

IF you you thinking about the Velociti 5.5 then just get the GTB combo.

[chilledoutuk]

"60 amps constant"

so are you telling me that a gtb and velocity 5.5 would drain a 6000mah 2s lipo battery in 6mins i think not my friend.

[tcolesen]

That's the thing. You just can't say that a motor will pull X number of amps. It doesn't work that way. One can figure out the approximate average number of amps a motor pulls by using the runtime and the battery capacity. The equation is:
60mins. / runtime (in minutes) x capacity (in amp-hours)

So, if you get 10mins runtime with a GP3300, assuming that the GP3300 will give its rated capacity the average number of amps pulled would be 19.8amps.

[aqualato1]

Yes ~60 amps. Heres a test that Optimaman did a while back with a LiPo batt: http://forums.radiocontrolzone.com/showthread.php?t=207553&highlight=GTB+amp+draw.

The amp draw was like 60 only because he was over gearing to get top speed.

[tcolesen]

I don't know, I wouldn't consider that normal driving. "5 minutes of doing circles back and forth on my driveway" That will more than just raise the amp draw, especially when the motor is overgeared!

[aqualato1]

True