Cant we do this?

[Xfactor]

I had 2 burnt M2000 ( from HC )
I replaced the fets with FS3206
better yield and back emf tolerance
The M2000 ( turnigy monster) ... can successfully stack 2 FET arrays using the one controller board.
I assembled one of these on order for a 33% EDGE540.
6AWG to battery bus ( total ) 12S4P
Soldered direct to motor
Added a bank of // 16x440uf 63V low esr high yield to inputs
heatsinking/cooling the largest issue as these created massive heat pockets when pushing 18KW peak .... makes for some very hot airflow through the vents
Client gave a thumbsup after several flights.. all I know..he later returned interstate all smiles...

Same applet at 12S240A manuf for 700 heli with staged governor output.
Cap bank was larger than the 12S1P due high yield required for 3D.!
A popular mod in big 3D.

DocWayne

Thanks for the info wayne. I was thinking the same thing I wisth there was a way to bypass the 51 volt govenor. I realize above 48 volts can be fatal.
when you hook all these caps up parallel are you merely increasing the capacitance? If so why not select one big one rated at 63 volts?

[Xfactor]

I have already beefed up the turnigy to accept 8 ga wire. Check it out. Whos a good supplier of the 63volt 470 uf caps?

[Xfactor]

Wayne the FS3206? cant find that whos the manufacturer can u get me a spec sheet?

[Xfactor]

Is there any pc software for the monster 2000?

[Xfactor]

Found it here:http://datasheet.octopart.com/IRFS32...eet-135386.pdf anyone interested in this not good with soldering hit me up. Anyone got a bad turnigy m2000 they want to sell?

[AndyKunz]

But these esc's drive a sinusoidial wave (AC).

The battery is what you have to worry about. It's DC.

And if (when?) the ESC fails, it could leave you with a DC output to the motor. No zero crossings!

when you hook all these caps up parallel are you merely increasing the capacitance? If so why not select one big one rated at 63 volts?

Cooling. Price. Size/shape. Availability. Also, these are low-ESR caps, so they're a little special and are designed to accept a large AC component. You need to read the whole datasheet on them, not just the V and C ratings, to understand why a particular cap is selected. Otherwise you might be tempted to use tantalums and end up shooting your customers.

Andy

[drwayne]

Thanks for the info wayne. I was thinking the same thing I wisth there was a way to bypass the 51 volt govenor. I realize above 48 volts can be fatal.
when you hook all these caps up parallel are you merely increasing the capacitance? If so why not select one big one rated at 63 volts?

Dude/Dudette ( for want of a real first name)



The V limit you fight is software ... recode.... burn to eeprom .. replace board.
The BANG you fight when you exceed that software V limit is a component failure thing ... live and learn ..



Unlike mains power at 50/60Hz we are dealing with 30-100kHz where low esr high output is not viable from 'larger capacitors' ..
The refresh rate overheats caps ... would melt standoffs ... where a few more littl'uns bypasses that grief
The cap bank also covers you if/when one fails .. why risk all to a highly stressed individual ?
KISS works best.

"AC output is sinusoidal.. "
sure dont look it .... shows a staged square wave on the screen ..
fact defeats fiction.

We all hope to achieve giddy heights of rc esc power conversion/control..
Research more from books , in the lab...and out in the real world ( out of class )
Experiment more
Blow bucket loads more to bits

Acknowledge it's more than fets and capacitors..
Fets are the horses before the cart...
..... but the driver guides them all.



DocWayne


ps..
HiFei M2000 is stick program only.
HiFei Swordfish240HV controller is upgraded from M2000 circuit, and is usb programmable.,, is compatible for M2000 retrofit.
Be aware you would need new firmware code to suit .

psx2. Ive a burst M2000 complete ( separated boards in a box .. controller is ok )
cost you postage.

[drwayne]

I have already beefed up the turnigy to accept 8 ga wire. Check it out. Whos a good supplier of the 63volt 470 uf caps?

unless you pin mount to a board, do not solder plug direct..
the fatigue fracture rates on pcb surface soldered sockets is extreme.

Add voltage/current ( HEAT) and all adds up to an expensive electric BBQ

a short length of 8AWG should suffice to protect the board from connect 'wriggle' failures.

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[Xfactor]

Thanks.

[Xfactor]

Yeah your right it is an ac-like wave created buy different duty cyle levels on the pwm rite? looks ac but at closer inspection its like a stairs up a hill and down the hill.Are you familiar with the propeller chip by parallax. Thinking of using it as the brain for my esc. It has mini usb right on top.All those pwm calculation can be set up with a formula in an excel worksheet then pasted to the code the mpu. Correct? I remember in lab using a propeller chip fets and transistors to create an ac like wave we measured with the scope. I remember the hardware was set up basically like an h-bridge.How hard would it be to impliment sensors for closed loop on an m2000 or is an esc from scratch an easier task?Look pics of the m2000 with it new fets.In drivers isnt there some models that simply wont allow shoot thru?

[Xfactor]

Wayne while I have you ear I have a brushed motor that i want to get the IO and internal resistance. I assume that I can run the motor at say 10 volts unloaded with an amp meter and get the IO? What about the internal resistance?

[drwayne]

wow.
Io.. sounds the biz
Ir .. perhaps a ohm meter ?
perhaps a radioshack multimeter ?
perhaps feed a known voltage through the windings and measure the voltage drop on a cro .. ?
this is all fairly fundamental stuff.
Did you miss that class ?
W

[Xfactor]

Idle current. Believe it or not motors is part of the commercial electronic dept at school. I had a general Idea just wanted to be sure. And no im talking about two seperate things idle current and internal resistance. No need to keep referring to school I have a 3.75 gpa FYI.

[Xfactor]

Wayne
Why refer back to a book when you can just ask someone in the middle of a thread?I guess thats the way to go then u dont have to have people question your intelligence. Full fledged engineers ask question why cant I? Not to mention being an engineer does not give you personal experience with all things electronic.Love the help but the remarks about class whats the point?

[AndyKunz]

Why don't you just read and digest the TI and MCP app notes on BLDC controllers? They answer all these questions and more, plus you get FREE schematics with some of them!

Andy