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Aceldama
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03.10.2009, 11:07 AM

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Originally Posted by mtsmat2008 View Post
well that motor (3674) is only rated for 4s, so wat did guy the expect that motor isnt designed to run at 52000+ rpm.the only hobbywing motor rated for 6s is the larger 4465,2000kv which i plan to run in my upcoming 12-13lbs. lst2 coversion on 5s, maybe 6s but it'll probably wont be able to handle that speed.
That's a good point, I didn't realize it was only rated for 4S.

The cheapest 4465 combo I see on e-bay is $234. That's not bad, but for that price I'd sooner get:
-HW 150A: $118 (eBay). I'd much rather buy this from Mike, so I'll wait for him to stock them.
-Medusa 70mm: $124 (RC-Monster). Or $140 for CC/Neu or Medusa 80mm.

Total: $242. And I'd add in the Advanced programming card when RC-Monster gets them in. For a $10 difference I have to hear a LOT of good things about the HW motor to select it over the Medusa.
   
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BrianG
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03.10.2009, 11:48 AM

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Originally Posted by jsr View Post
...BTW, can you comment on how the FETs in the 80A seem to come out with higher current capability than those in the 150A? 62A x 3 = 186A vs. 26A x 6 = 154A. Seems strange unless I'm looking at it wrong.
Actually, the 150A has 24 FETs, so it's 26A x 4. But anyway, you can't look at just the current ratings. The RdsOn, switching speed (or slew rate), and power dissipation have to be taken into consideration as well. Even something as seemingly innocent as gate capacitance can (and does) have an effect on switching speed. An FET might have a higher raw current rating, but if the slew rate is slower and/or the RdsOn value is higher, there will be more heat (power dissipation) and might exceed the safe value. So, they may be derating the current more than usual on the 150A to compensate.

And all electronic hi-power devices need a certain amount of cooling surface area to function effectively, be it PCB traces or heatsink. These ESCs are VERY small considering the amount of power they can funnel to the load. So, if an FET is spec'd at a certain current rating, but the actual amount of cooling area is below the recommended value, then they have to derate the current even further.

Just looking at FET specs is one part, it is also important how the circuit is implemented. Short of reverse-engineering the entire ESC and taking a boat load of measurement with meters and o-scopes, it is all just speculation. The best we can do when we look at the specs is to see if the advertised spec is even possible.
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Dagger Thrasher
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03.10.2009, 11:41 AM

Have you tried increasing the timing on the MMM? That's the only other variable I can think of. The 6mph difference just doesn't make sense otherwise, so maybe the HW ESC is running its motors at a higher timing?
   
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jzemaxx
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03.10.2009, 11:42 AM

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Originally Posted by Dagger Thrasher View Post
Have you tried increasing the timing on the MMM? That's the only other variable I can think of. The 6mph difference just doesn't make sense otherwise, so maybe the HW ESC is running its motors at a higher timing?
I already posted that. The HW default runs the motor at 15 deg timing. So we set the MMM at 15 deg as well.


Serpent S811-E Tekin
Revo 3.3 BL- 1515 1Y
Mugen MBX6 NEU/MMM
Mugen MBX6-T NEU/MMM
Losi LST2.0 MT NEU/MMM
Losi 8T RTR 2.0 NEU/MMM
Losi 8T 2.0 NEU/MMM
Losi 8B-E 2.0 NEU/MMM
   
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Dagger Thrasher
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03.10.2009, 11:46 AM

Ah, sorry. Must have missed that part of the thread.
   
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jzemaxx
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03.11.2009, 10:07 AM

Ok guys just picked up (yesterday arrived) a Medusa to see how it stacks up. (3670-2300kv). So now we have the 2350 KV HW 36-74, the Neu/MMM 2200KV and Medusa 36-70 2300KV


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Revo 3.3 BL- 1515 1Y
Mugen MBX6 NEU/MMM
Mugen MBX6-T NEU/MMM
Losi LST2.0 MT NEU/MMM
Losi 8T RTR 2.0 NEU/MMM
Losi 8T 2.0 NEU/MMM
Losi 8B-E 2.0 NEU/MMM
   
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mtsmat2008
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03.11.2009, 10:24 AM

that was my other option motor wise. i was think about starting a new thread just for it lol. definitely going with the HW esc for the $ but the cc 2200kv/ hw 2000kv/ medusa 2300kv are all great comparisons for their performance and price for any MT brushless conversion. The medusa motors also have a two year warranty which is definitely a MAJOR +!
   
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jzemaxx
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03.11.2009, 11:58 AM

We'll see how it stacks up. We are going to take it to the track and run all of them on 4S parallel for 30 min times. I want to see run times and heat for each one. I'm racing now, so that is what is important for me at least. The speed stuff....nothing but a NEU for me....tried the others, they come apart at 90,000rpms....my 1521 didn't. Bulletproof motor...


Serpent S811-E Tekin
Revo 3.3 BL- 1515 1Y
Mugen MBX6 NEU/MMM
Mugen MBX6-T NEU/MMM
Losi LST2.0 MT NEU/MMM
Losi 8T RTR 2.0 NEU/MMM
Losi 8T 2.0 NEU/MMM
Losi 8B-E 2.0 NEU/MMM
   
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jzemaxx
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03.12.2009, 12:34 AM

Ok guys something I didn't think about and maybe some of the big brains can answer this. The HW150 automatically is set to 15 deg of timing. Now the question is, could this cause a problem with a Neu/CC motor. I know its a 4 pole vs HW 3674 2 pole motor. Do I need to maybe try lower timing on the NEU/CC to see if it picks up speed?? I read that the 4 poles like low timing versus high timing. 15 deg is quite a bit and didn't think of that. I just set both controllers to 15 deg since the HW was already set to that.


Serpent S811-E Tekin
Revo 3.3 BL- 1515 1Y
Mugen MBX6 NEU/MMM
Mugen MBX6-T NEU/MMM
Losi LST2.0 MT NEU/MMM
Losi 8T RTR 2.0 NEU/MMM
Losi 8T 2.0 NEU/MMM
Losi 8B-E 2.0 NEU/MMM
   
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lutach
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03.12.2009, 02:12 PM

Quote:
Originally Posted by jzemaxx View Post
Ok guys something I didn't think about and maybe some of the big brains can answer this. The HW150 automatically is set to 15 deg of timing. Now the question is, could this cause a problem with a Neu/CC motor. I know its a 4 pole vs HW 3674 2 pole motor. Do I need to maybe try lower timing on the NEU/CC to see if it picks up speed?? I read that the 4 poles like low timing versus high timing. 15 deg is quite a bit and didn't think of that. I just set both controllers to 15 deg since the HW was already set to that.
It actually depends on who you ask. I've heard many things like, "Our ESC switchs automacally to higher timing will gain more speed and power". I like the fact that some companies offer a simple answer. I go with 0 to 5 (Low) for 2 pole, 5 to 10 (Mid) for 4 pole, 10-15 (High) for 6 pole and outrunners likes 15 and more depending on the pole. One thing I do know is that D wound motors likes lower timing. I have yet to see any speed benefits from higher timing. I have seen heat from higher timing, but no other benefit as some say you can gain power from a higher timing. But what works for me will not always work for somebody else.
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scarletboa
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03.16.2009, 12:54 AM

where is the cheapest place to get an ezrun 150A esc+motor combo? i am in the process of converting my savage x 4.6 rtr to brushless.

first post
   
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q8-maxx
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03.16.2009, 01:07 AM

I buy one from ebay for $125 with program card but still in shipping and not arrived. this is my first time I order from ebay

sorry edit the post

dont get the combo the motor is not good just buy medusa or neu motors from here


MMM v1 zippy 2x3s 5000mah neu 1y 1/8 diff's
MMM v3 Rc-monster 2x2s 5200mah-HC medusa 36-70-2300kv
Pic's - video - youtube video's

Last edited by q8-maxx; 03.16.2009 at 01:10 AM.
   
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himalaya
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03.16.2009, 11:55 AM

Quote:
Originally Posted by q8-maxx View Post

dont get the combo the motor is not good just buy medusa or neu motors from here
+1. buy the ESC, stay away from their shabby motor. I've seen countless rotor failures here.


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Aceldama
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03.16.2009, 12:29 PM

Quote:
Originally Posted by himalaya View Post
+1. buy the ESC, stay away from their shabby motor. I've seen countless rotor failures here.
This is what I'm planning on doing once RC-Monster has the 150A in stock. I'm thinking the HW150 will be a nice combo with the 70mm Medusa... maybe 2000kv on 5s in a MBX5t.

The other thing I haven't heard about yet that I'd love more info on is this: Professional programming box
   
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fastbaja5b
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03.16.2009, 01:29 AM

I recall when I ran a X1CR buggy with a Medusa 36-60-2000 on 4s, the HW 80A speedy felt a LOT faster than when I ran the MMMV3, and I made sure everything was set up alike.

Now hearing more and more failures with the MMMV3 and yet to hear of a HW speedy failing, is it worth my while ditching the MMM from the flux and putting in a HW150 speedy just so my set up is reliable?


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