Difference between 20120 and 12020??

[squeeforever]

the 9920 can handle peaks WAY higher than its rating. coolhand has run a 7xl on a 7020. the 6xl would be ok on the 9920 so a 7xl will be plenty...

[BrianG]

OK, 7xl and 9920 it is then!

I wish these BL motors would have more specs other than just the kv rating. At least power consumption would be nice. At least that way you can figure out the current draw for a particular number of cells to achieve 45-50k rpm.

[maxxdude1234]

Anyway, good luck getting 95amps out of sub C cells for any period of time without them blowing up! A 7XL on 12 cells won't pull any where near 95 amps constant, maybe on 20+ cells it might

[BrianG]

Yeah, but I'm looking in the future. Eventually, I want to get Lipos or whatever is the best for power to weight ratio at that time. Even though lots of people run Lipos with no problems, I am still a bit leary due to the chance of destruction from undercharging/overcharging/puncturing. I'm going to wait until they are more stable and for the price to come down. Until then, I'll make do with sub-C's knowing that I won't unlock the full potential of any BL setup until I do break down and upgrade.

[GriffinRU]

Originally Posted by BrianG

OK, 7xl and 9920 it is then!

I wish these BL motors would have more specs other than just the kv rating. At least power consumption would be nice. At least that way you can figure out the current draw for a particular number of cells to achieve 45-50k rpm.

You have Kv, I and R ...
You have all the parameters to calculate power...

And some manufactures even provide efficiency over RPM or load data...

Artur

[BrianG]

Originally Posted by GriffinRU

You have Kv, I and R ...
You have all the parameters to calculate power...

And some manufactures even provide efficiency over RPM or load data...

Artur

Where are the current and resistance (or impedance) ratings? All I see are the number of turns and the kv rating. Sepcifically, the BK Wanderers?

[GriffinRU]

Originally Posted by BrianG

Where are the current and resistance (or impedance) ratings? All I see are the number of turns and the kv rating. Sepcifically, the BK Wanderers?

For feigao motors are on the motor can. I hope you can get the same info from BK as well. If not then it is not difficult to get the trend from feigao/nemesis to BK...

Artur

[BrianG]

Feigaos yes, no such luck for BK. The only detailed documents they offer is for series 10, 15, 19, 22, Basic, and Basic XL. The bk-electronics site simply lists the turns and kv ratings. On the "dimensions" page, it does list the max rpm range (80,000 rpm!) and max current (which is 120A for the XLs). Of course that max current will depend on the number of turns.

The best one can hope for is that someone else with deep pockets and a desire to try various motors can vouch for a specific model - but then there are the variables like truck weight and number of cells to consider. You'd think with the popularity BL motors are gaining that manufacturers would list all the specs so consumers could make an educated buying decision.

However, with the help of several people, I think the BK Wanderer 7XL or 8XL are the best bets.

[BrianG]

By the way, the answer to this thread is found in the Warrior's manual (http://www.bk-electronics.com/man_warrior_eng.pdf)

For the MICRO-family of controllers programming of timing and motor run-up are possible by use of PC software and programming cable. Controllers have been optimized for partial-load applications through electronic motor timing. In case of mechanical blockage controller reduces current to protect motor. Controller self-tests prevent malfunction and turns controller off.