MMM: No brushed motor limit?

[crazyjr]

Most of the other esc's are tested different from castle, some are even theoretical. But i'm pretty sure castle tortures theirs. I was running two MM's, one 7XL on 5s and the other 9xl on 5s, while the esc's got hot, they never flinched or thermalled. Hats off to castle for making two of the absolute best esc's made. Now that most of the problems are sorted out, It may be time for me to get one (at least) of the MMM's. I plan one for my 1515/2.5d and the other for a 2250 lehner, Possibly in a Summit

[BrianG]

I think most ESC makers simply lump the FET current ratings together and that's the current rating. But, anyone who takes a few minutes to look at a datasheet will see that those ratings are usually at 25*C (77*F). I tend to shoot for temps around 30*F above ambient max, so I'd have to run at 47*F ambient just to meet the FET temp ratings, and that is assuming adequate airflow on a perfect heatsink.

From what I've seen, Castle tends to rate their products at temperatures found on earth during normal running. Like their HV110. Even at around 160*F FET temps, the FETs still are capable of ~140A looking purely at the temperature derating curve. To match other makers' specs, they would have to rate the HV110 at something closer to HV180 or more.

I can see this helping Castle, and hurting them at the same time. A newb looking at the specs printed on the box will assume the other ESC is better because of the inflated ratings. Anyone "in the know" will see through that BS and figure the ESC is properly rated, but how many people fit that profile (think: the typical trx member)?

I think Castle should put some type of dual rating system on their boxes. One showing the real and proper rating, and one stating the rating if using other manufacturers' rating methods.

[e-mike]

thanks BrianG!!!!!i learn every day when i read your threadbut if i completely understand a lot of esc are overrated!!???a the castle esc are simply correctly rated????and for the mmm it doesn't mean that the esc seem to handle a lot of power!!???

[BrianG]

Yeah, other ESCs tend ot be "optimistically" rated, while Castle seems to be more realistic.

Gotta remember that the MMM is capable of 120A and 6s - that's 2664w of power, or over 3.5HP! So, yes, it handles a lot of power.

[Pdelcast]

Originally Posted by e-mike

thanks!!!well if the mmm is able to handle a 1521.......i was scared because the new "BRAND L" (edited by Patrick) esc can handle 160amps continously!!??and the mmm 120amps

"Brand L" -- their new 1/8th scale controller shuts down in just a few seconds on our MMM bench test -- where the MMM will run continuously (at 120A...)

[e-mike]

Originally Posted by Pdelcast

"Brand L" -- their new 1/8th scale controller shuts down in just a few seconds on our MMM bench test -- where the MMM will run continuously (at 120A...)

thanks for the edit pdelcasthowever im not afraid about the fact that the mmm handle ''ONLY''120amp

[crazyjr]

Originally Posted by BrianG

Yeah, other ESCs tend ot be "optimistically" rated, while Castle seems to be more realistic.

Gotta remember that the MMM is capable of 120A and 6s - that's 2664w of power, or over 3.5HP! So, yes, it handles a lot of power.

I did close to that with an MGM 16018 and a 2250 lehner (2584W peak to be exact) In my twin force, that is some freaky nasty power

[What's_nitro?]

Originally Posted by crazyjr

.....that is some freaky nasty power

Indeed.

[crazyjr]

Originally Posted by What's_nitro?

Indeed.

My hands were shaking uncontrolably the first time i dropped the hammer on that setup, what a rush

[jordan...]

Originally Posted by MetalMan

Anybody got a 24v 6HP brushed motor they want to test the MMM's limits with?

Send me an MMM and i'll happily test it out

[What's_nitro?]

Try running a couple of these in parallel!!! THAT would impress me!

http://www.robotmarketplace.com/prod...G-S28-150.html

[lincpimp]

Originally Posted by What's_nitro?

Try running a couple of these in parallel!!! THAT would impress me!

http://www.robotmarketplace.com/prod...G-S28-150.html

Dang!!! 3.5lb motor!! Don't drop that on your foot...

[What's_nitro?]

Machined 6061 case, 1/2 steel shaft, 1/4" thick NdFeB magnets and a 4-pole armature! To top it all off, 82% efficiency! I love these things!

I used one back in HS in a Battlebot my shop class built. It spun up a 24 pound steel bar to 2000 RpM (3:1 chain drive) in about a second.

[lincpimp]

Originally Posted by What's_nitro?

Machined 6061 case, 1/2 steel shaft, 1/4" thick NdFeB magnets and a 4-pole armature! To top it all off, 82% efficiency! I love these things!

I used one back in HS in a Battlebot my shop class built. It spun up a 24 pound steel bar to 2000 RpM (3:1 chain drive) in about a second.

What did you call this spinning bar o' death? The shin basher? Sounds like something fun to chase drunks with... watch out Shaun (tdc57)!!!

[What's_nitro?]

It was called "Stop Bot" because we used a 1/4" thick piece of 6061 as the top that was the exact dimensions of a stop sign and painted just like one. It was about 8" tall and the steel bar extended down the sides.