Tutorial Monster Moto Shield acts as a single motor driver = more power!

Hello,

I am trying to wire two IBT-2 for one motor, but I have a wiring question :

Do I wire like this :

IBT-2 (1) :
IBT-2 (1)= M+ to Motor +
IBT-2(1)= M- on M- of The second IBT

IBT-2 (2) :
IBT-2(2)= M+ to Motor -
IBT-2(2)= M- on M- of first IBT

And

IBT-2 (1) :
IBT-2 (1) B+ To PSU V+
IBT-2(1) B- To PSU V-

IBT-2 (2) :
IBT-2(2) B+ To PSU V+ ( Same output as IBT (1) )
IBT-2(2) B- To PSU V - ( Same output as IBT (1) )

Is this correct ?
Or do I need to plug the PSU +/- on only one IBT-2 B+/B-, or even something else ?.
And of course The inputs from arduino together...

Thanks,

Rémi.

No that wiring is wrong...
First of all why use two IBT-2? one of them can deliver 43A? I use those on my CNC machine. They are limited to 26V I think...
Just use one... What kind of motor are you using? If you really need to use two you should connect everything in parallel. But even then current sharing is not guaranteed. Even two devices are not the same and one of the drivers will be conducting more current than the other...

I made a driver for my simulator and I made a H-bridge from scratch. I used IGBT transistors and that thing can carry alot of power. I think I over designd the thing because it can drive about 600V and 50A

So if one IBT-2 is not enough for you, I think you should build a H-bridge. I don't know of any ICs that can carry more juice... Maybe I'm wrong

I also have a moto monster and i connected it like many of you did but mine doesn't work. If i use one of them it does but as soon as I connect them together I doesn't work...
Anyone else expiriencing the same issue?

The IBT-2 driver which uses 2 half bridge bts7960b chips are actually rated at 18v@43A, infineon in their deceptive data sheets have max Vs of 28v but will definitely not put out anything close to 43A at that voltage. In other datasheets for the same series of chips they list 2 values of Vs, they are 8v-18v Vs(nor) and 18v-28v as Vs(ext)

I wouldn't recommend using dual ibt-2 if your going to exceed 43A@24v due to reasons given by tadythefish in previous post.
I would use dual ibt-2 if I was below 43A but was having heat issues, using 2 drivers not so much increases amperage but reduces (halves) Ron resistance and therefore shares the heat dissipation between the 2 drivers.



Anyway I modified a picture from smc connection diagram and have drawn the 2 methods of connecting dual IBT-2.
Configuration B would be the best method as you don't want to add to the different switching times due to differing lead lengths.

NB I haven't tried using IBT-2 but be aware that if a leg shutdowns before its paralleled twin switches on it could cause a short to the motor outputs, hence why you still don't want to exceed the ratings.

Mine work at 24V with no problems.. I don't draw anything near 43A. I think mine work at 20A max and about 10A constant without using fans.... But i wouldn't parallel them.
Mosfets inside have a positive temperature coeficient (with rising temperature the Rds increases) but that doesn't guarantee proper current sharing!

Why not checking this out @Remishka? Burning drivers can be exciting, unfortunately I don't have so much experience in this lol. Seriously I suggest to make sure you have wired all correctly and then start your engines. If all is going well we will add this to the FAQ. If not you get 500 coins as a consolation

Hello everyone, thanks for your interest.


Tadythefish : Why two IBT'S ? Because my motors draws alot of amps for the reverse ( they are MY1016 : 24v/15A with a 1000w/24v psu ) I guess it cause when I plugged everything and I increased PWMmax in SMC3 it made a little power shutdown when motors go reverse when above PWMmax=70, and when I did put it even further like a fireman in want of action : PWMmax=130 they got hot and one side of ibt burned
Congrats for your H-bridge, if the experiments doesn't go well and I burn the other 8 Ibt's I received I will consider doing the same for sure.
For the Motomonsters Silent-Chill had some issues with those, check his thread about it : CHEAP CHINESE MONSTER MOTO CLONES AND PROBLEMS

OZHEAT : Thank you so much ! It shouldn't exceed 43A/24V because my power supply is 24V/1000W/42A

Pit : Do you mean the OZHEAD wiring ? Yes i'm gonna try this, with less powerfull motors and PSU and with thermal paste on the IBT's first, then on the MY1016+1000W PSU.

I'll tell you how it does next week, thanks again everyone.

Rémi.

I have exactly the same motors and the same PSU (industrial 3 phase... 60A nominal and 120A max)
I used IBTs and burned them all so for saving you trouble and if you know how to build electronic stuff I would like to spare you alot of nerves and advise you do build a H-bridge!
I built it with IGBTs and IR21844, some electrolytic caps, some decoupling caps, transient voltage supressors and shottkey diodes.. The only thing to watch out with all N-channel MOSFETs or IGBTs that you never drive the PWM to 100%. Max would be 90 or maybe 95%.
The drivers have bootstrap capacitors that provide floating voltage for the upper switching devices and they need to be rechared frequently. So if you drive the PWM 100% for a few seconds the cap will graduatly discharge and the switching device will go in to its linear condiction area... There it wil warm up so fast that it will blow up...
If you want to build a h-bridge I can take some time and draw the schematic of mine.
I am currently building a brand new controller that works via ethernet and i will be dismantling the old controllet. I can't give it to you because i promised it to my friend but i can draw up the schematic and help you with some guide lines and tips

Here is a video demo of our first tests...
I am biulding a new one that will support 2DOF and traction loss (3 servos). It will be configurable via webserver and it will get commands from game engine via UDP and gamedash.. It will also drive my GSXR dash with the same processor

Hi mate, your h-bridge is very interesting, I suggest to open a new thread and honestly sharing your drawings or schematics.

I can do that.. But i will need some time... I wotk my projects from my head.. I don't draw schematics or pcbs... If i make a pcb in eagle i dont use symbols u just put vias on the board and connect them.. The downside is that only I know how to populate the board.. But i will draw a schematic and share my knowlidge if people don't know how to build such things

Hey,

The PSU is 1000W/42A/24V not the 60/120A.
I have a little stock of IBT's to burn or even better to use, so for now I'm still going this route. ( as Ericracer made it work with parallel IBT's ).

But still, yes I am very interested in your H-Bridge schematic, I have a little experience as I've done some Mic Preamps/Psu's and guitar effects pedals plus reflowing/reballing graphical chipsets, but making PCB's is not my fav hobby... As Pit says, they look interesting and you should open a thread about it, so everyone could enjoy it !

I'll be back showing how IBT's can work/burn and if I really can't do it with those, then I'll make the H-bridge !

Thanks for you kindness,

Rémi.

by all means try it if it works I would be very happy for you... this is the simplest way... making a h-bridge can be tricky it is mandatory to make a PCB for a h-bridge unless you use IGBT bricks or modules ( these monsters can handle 300A ). The PCB layout is also crucial. The tracks need to be thick and short. Decoupling capacitors need to be placed as close to the switching devices as possible to minimise stray inductance... At high frequency switching speeds and high currents basic logic fails. You need to strast considering the high frequency effects on copper tracks and voltage spikes that can go as high as 80V or higher when powering a motor with only 15-24V. You need to clamp the spikes to the power rails and limit the dV/dt rise and fall times
I will start a thread with a schematic and some basic guidelines how to design a good h-bridge. But you should all know that even that I made a working h-bridge I also don't know everything. Some time ago I made a servo controller for a CNC machine. The bridge had 1200V 100A IGBTs and the motor was powered with 200V and was rated for 20A. That bridge never worked and I stil don't know why. It burned one of the IGBTs very fast and everything was designed to work with alot of head room. I even used copper bus bars for connections. And it still did not work. Maybe the motor was at fault i don't know.
All I am saying be prepared for some burnt transistors

Hello,

I did some tests following OZHEAT wirings :

A wiring : Works good, I tried first with little motors + 12V PSU, then on T-1000-24 PSU + My1016 motor. Played a bit with SMC3 values, making motors move break and reverse several times, fastly and slowly. Nice, it didn't get hot or anything. Bravo !

B wiring : Did not work, tried only with same little motors and 12V PSU. Double checked wiring, did it all again, still Nothing, either in SMC3 Mode 1 and Mode 2.
They didn't burned or got hot.

However, with the T1000-24V PSU / MY1016 / A wiring Parallel IBT's ( with thermal paste on it ) when above PWMmax=80 my PSU still shuts down briefly when braking or reversing, I guess this PSU is not powerfull enough ( even with only 1 motor + parallel Ibt's wired ). The Ibt's had no problems and didn''t get hot. So my next adventure is to find a PSU that will suit better .

Thanks,

Rémi.

@Remishka when your test is finished honestly you could open a new thread by sharing your experiences, drawings, screenshots etc. If done you will get your 500 coins even the drivers did not blow away

I gave @Remishka 250 to enocourage him opening the new thread

I will, as soon as i put the pieces together again, gonna take some pictures of the frame/sit assembly and chain reductor too, it could interest some as it is mainly made from wood and wood turning on the lathe.

For the Parallel Ibt's wiring on FAQ we have to remove the B wiring and do the A drawing for motor 2 aswell on the picture for it to be clear. Either me or the original author OZHEAT if he prefers.

Rémi.

Nice to hear it is working I can't get my monster motor shield to work in parallel. Nothing if i wire A1 and B1, A2 and B2 or if I wire A1 and A2, B1 and B2.
The second wiring turns the motor a little and then the device goes into shutdown... I will have to bring out my oscilloscope and debug the thing :/

Hi,

I don't know much about Motomonsters and I don't come with very original solutions but maybe they could give you an idea :

Did you test them with a power meter to check polarity as Pit recomended ?.
Maybe you could use some fuses to prevent/detect any shorts ?.
Do you use wires that are strong enough ?.
Maybe it makes your PSU act weird, a current spike or anything else, could you try with another one ?.
Does anything get hot ?.

Another thing I think about if you use SMC3 is checking setting and the PwmRev and put it to Rev=20-30 minimum ( or maybe MM's in parallel needs more ? ). As when I tested some little motors once the motors moved a bit in one direction and didn't go to the other one with Rev=0, increased it and then it started to work nice.

You should consider trying to contact Silent-Chill as it looks like he has alot of experience with those MM's, maybe he had some similar problems as yours.

Have a good day, hope you'll figure it out.

Rémi.

I have a 30A bench supply.. Ilimited the current to 1A.. No i don't use an SMC.. I made my own controller.. I think i figured out what was wrong... The microcontroller is outputing 3.3V.. As the data sheet of the moto monster states it is enough for a logic 1... So that is why a single channel worked.. But now I am buffering the outputs from 0-3.3 to 0-5v and it seem to give of some life.. I just need to connect an encoder so I can test if it works with PID control.. It was spining in one direction

@Remishka
Good to see that you got it working in config A.
As for config B not working, did you connect pins 1-2 & 3-4?


There is no good reason why it would not work, you can think of each bts7960 chip as a half bridge (the vnh2sp30 is a full bridge per chip) changing the usage configuration makes no difference to the chip as there is no interactions between each half bridge.
Do note that each chip has its own protections and limitations and will shutdown/disable independently of other half bridges.
Maybe you can test configuration B just using both left channels ie in standard mode but moving the second half bridge to the second board. If that works you can then start to parallel them, a quick tip leave the motor outputs unconnected and test voltages, better still is 2 leds back to back with a 330R resistor connected to motor outputs.
Smc3 uses the pwm to switch the left half bridge only and directly switching the right side.

As for the faq, try config B again as that is the config akin to what pit used on the mms and my preferred method aswell.
After that you can redraw and post your findings. Please do point out that the IBT-2 is a Driver, not a Controller.
cheers and good luck.