Current MM still ok on 4s?

[BrianG]

I don't think so. The MM is a great 12 cell/4s ESC rated for 100A. The MMM is a great 18 cell/6s ESC rated for ~200A. Almost triple the power capability for about 30% more cost. Much better bang for the buck IMO.

The MMM just needs the little bugs ironed out is all...

When the release grade MMM ships, it will be awesome.

[SunnyHouTX]

That's what I'm hoping.

I was just thinking out loud that we have a great ESC in the MM already. I am really not missing the MMM because I haven't got mine yet . The MM's (I have 4) are serving me well even though they handles about 5V less than the MMM and can handle 150+ amps with proper cooling. All my MM's are on 4S except one which is on 5S (double duty between my Rustler and truggy) and are reliable.

Can't wait for the 2nd batch of MMM's to start shipping...

BrianG, I agree with you that the MMM is an awesome deal for what we will be getting out of it.

[DRIFT_BUGGY]

Do many people have problems running 5S off the MM?

[SunnyHouTX]

The only problem I've had was when I forgot to run the cooling fan. Also, I have to bring the pack voltage down to about 20.6V. MM's a champ!

Edit: Here's a data log from my Rustler on 5S from a few weeks ago pushing around 1995 Watts:

[Jeremy1976]

Is a cooling fan needed on 4s?

[DRIFT_BUGGY]

Originally Posted by Jeremy1976

Is a cooling fan needed on 4s?

The ESC is rated for 3S (i think) so it would be best to, some even run 2 and running on 4S will require the external BEC

[SunnyHouTX]

I have a habit of using cooling fans on MM's above 4S. Definitely helps. The only thermalling I've had is when the fans aren't working.

[FG101C]

If I run the MM with 4s and a Neu 1515 1/Y do I "Have" to put a thicker guage wire in or will the stock be fine with the stock bullet connectors? I think I may stay off the track since that's where everything seems to break or burn.

Originally Posted by SunnyHouTX

Also, I used a MM that I just got back from CC as a replacement on my Rustler on a 5S discharged to 20.6V. Worked fine for a couple speed runs until it thermalled. I then realized that I had forgotten the y-harness for the cooling fans. The Rustler was pulling wheelies when I gave it full throttle at 76+mph. Can't wait to put the MMM from RC-Monster in there. Should see some good numbers...

O man what a lifesaver thanks, i just charged up two 7 cell packs let them sit for a few. till they dropped below 10v and walla they run. Awesome. Now i will be a little more patient for my mmm to come.

[SunnyHouTX]

Nice! Glad to be of help.

[Pdelcast]

Sunny --

Don't forget that the Eagletree response time is a little slow, and does some averaging on current. We measure 1200A peaks on our systems that the Eagletree shows as 120A peak.

So some setups (especially those that use very low resistance motors like the Neu motors) can be tough on an ESC.


As for the voltage on the MM -- when we changed from 36 FETs to 30 FETs on the MM, we also changed from ~2.2 milliohm FETs to ~1.5 milliohm FETs, so the newer MM can actually handle MORE current with fewer FETs (we reduced the FETs to make the MM easier to build.) The MM is copper limited on how much current it can handle (the limit is no longer the FETs, but how much copper we can cram into the circuit board.)

The MMM has 36 of the newer FETs, but a LOT more copper area to handle the current, and a LOT more cooling than the MM. It handles more than double the current of the MM.

Patrick, thanks for posting, let me cut through all the technical mumbo-jumbo. I want to buy a MMM but I need it in the next two weeks, should I just buy a MM or is the fabled "Second (coming) Batch" going to be shipping soon?

[SunnyHouTX]

Hey there Patrick,

I didn't really think about the response time and current averaging. Man, I'd love to have my cars hooked up to your machines to see the real currents under load.

But not to worry, I use cheapo Feigao/Traxxas VXL motors, so the ESC's are safe!

Thanks for the info on the differences in the old and new MM. Given that, It's a good thing that I design my systems to top out at about 120A - 125A (albeit read off an EagleTree). The only time I've had failures were when A123's were involved, due to negligence on my part.

I also have a MMM on the way from RC-Monster. Waiting is very hard, especially knowing how much better it is than the MM. Any idea when the 2nd batch will be in our midst?

[TexasSP]

The second batch is a hot topic. I am waiting for the second batch to get my first batch esc which was sent in for repair and unrepairable. I know I and the others for repair are supposed to be at the top of the list and the second batch was expected to start around now, hopefully a word soon?