Mamba Max Question - RC-Monster Forums

GT4X · **Mamba Max Question -** 07.19.2006, 05:45 PM

Hi Guys,

I would like to know if I can use Castle's Mamba Max with my Feigao 540C 8XL Brushless Motor?

Thanks,
Kurt Knight

MetalMan · 07.19.2006, 06:23 PM

Someone was going to be trying the Mamba Max with a 7XL on 12 cells I believe, but I haven't heard about it yet. You might be able to do it. IMO, it should work.

BrianG · 07.19.2006, 07:33 PM

IMO, I wouldn't run a 7XL on the Mamba. According to the Feigao chart, a 7XL will draw up to 95A, which is awful close to the Mamba's 100A rating. While it should work, I wouldn't be surprised if it heats up quite a bit. To allow a safety margin, I like to get an ESC that can handle ~20% more current than the motor will pull. This will help the FETs work less and allows for a little headroom if a motor actually pulls more current than advertised. An 8XL can draw up to 83A, which is right at 20%. This 20% margin is purely something I like to do and it has worked fine so far. I just thought I'd throw it out there...

coolhandcountry · 07.19.2006, 07:36 PM

If you do run it make sure to gear it a little conservative. It make it draw less amps that way.

Brian just cause they rate the motor at a 95 amp draw don't mean that is the maxx. Dafni had a 8 or 9L that drew 130 amp spike.

BrianG · 07.19.2006, 07:54 PM

Quote:

Originally Posted by coolhandcountry

Brian just cause they rate the motor at a 95 amp draw don't mean that is the maxx. Dafni had a 8 or 9L that drew 130 amp spike.

All the more reason for a safety margin...

neweuser · 07.19.2006, 11:14 PM

How do you figure amp draw? just a question i guess?

Gustav · 07.20.2006, 01:09 AM

I don't think you can figure it,beyond guessing a rough ballpark anyway,you just have to measure it.

Those figures are only useful to show the relative difference between motors,but as for guessing the actual amp draw in a car,too many variables.

BrianG · 07.20.2006, 01:17 AM

Even with the same motor, other factors will determine current draw: weight of the truck, driving style, etc. The best way to tell for sure is to record the current value over time. I haven't used this, but it sounds good: http://www.eagletreesystems.com/MicroPower/micro.htm

07.20.2006, 06:28 AM

That'd be a good thing to build into the Nomadio sensor... Curent draw meter. Hint hint mister nomadio technical supervisor guy!

SpEEdyBL · 07.20.2006, 02:00 PM

100 amps is a continuous rating and so is 95 for the motor. Btw, the neither the 7xl or the 8xl will be drawing anwhere near that amount continuously. Typical continuous currents should around 20-40 amps. Even at 40 amps, that's about 6 minutes of runtime with 4200 mah cells. The main thing that will cause heat is the bec, so use u-bec instead.

crazyjr · 07.20.2006, 10:37 PM

Quote:

Originally Posted by MetalMan

Someone was going to be trying the Mamba Max with a 7XL on 12 cells I believe, but I haven't heard about it yet. You might be able to do it. IMO, it should work.

Thats me and i still intend to try it, just want to get more familar with the system. The 5700 system i got is the most unbelievable setup i have ever seen for 1/10 cars and trucks. Comparing this to a Novak is like comparing Yokozuna to Spike Dudley