Questions Regarding Alt. FW & GUI setup

[speedy]

HI jsmith2307 :

How is it going with you ? ... Is there any update ?.


spe edy

[jsmith2307]

Greetings!

SensLO and SensHI realy sets upper and lower limits for sensors (potentiometers).

Ale,it worked! BUT...I just burned up another Pololu high powered 24volt 23amps motor driver.....AGAIN!!!!!
I've checked all of the usual suspects. Then, I moved my ground to another site.... this one goes direct to the ground of the plug!
Scenario: What happens is this.. first I open up Sender (Extractor), then I open up Profiler (Converter), then I open flight sim 2004, AND finally I flip the switch on the simulator and everything hums along like it is supposed to but if I get the sequence wrong for example: If I flip the switch to the simulator first, then I hear a pop, and check the 2ea 20 amp fuses and they are blown, and on further examanation I find not only are the fuses blown so are my motor drivers!! This can't be normal!! It only happens when I get out of sequence, then it becomes disastrous.
jsmith2307

[prilad]

I just burned up another Pololu high powered 24volt 23amps motor driver.....AGAIN!!!!!

It's very strange. Please show me the wiring(connection) diagram between AMC and motor driver.

[crs2012]

Greetings,

Congratulations on beginning your journey with your sim!
Sorry to see that you are having difficulty getting things stabilized.

There are several possibilities based on the little information available in this project thread at this moment to narrow problem and solution.
So I will make some assumptions and offer some basic troubleshooting tips.

Incorrect placement of fuses.
Incorrect gauge of wiring.
faulty electronics, faulty power supply, faulty power outlet (Your wall outlet ground might be faulty, check EVERYTHING, assume nothing)
Incorrect motor settings in Pololu motor controller software.
Incorrect motors specs with motor controller. ( too much amp draw from motors blowing the boards )
Incorrect power supply for motors.
faulty soldering on the boards ( did you have to solder your own wires to the boards? ).

These are some major signs of possible causes for burning up a board when turning on the power.

Before attaching electronics or simulator.
What is the amp draw on the motors?
What is the amp draw under heavy load?
You need to know this first before continuing with other possible trouble shooting.
You need to know that your motors are not out of spec for the boards you are using.
Did you burn 1 board or ALL boards at the same time? This would help to narrow down issues as well.

I have a few theories to throw your way, without having too much information to go by.
So, I will be assuming everything based on this board below from the choices available from pololu which is 24v.
Are you referring to burning up Pololu Simple High-Power Motor Controller 24v23?
http://www.pololu.com/catalog/product/1383?

I'm asking because you didn't mention what you set the motor settings with the pololu motor controller software.
This should be first step before attaching any kind of load to the motors.
motor settings has to be set stable before continuing with simulator movement limit setting.

Note: The power capacitor has a significant effect on performance; the included capacitor is the minimum size recommended, and bigger ones can be added if there is space. A bigger capacitor might be required if the power supply is poor or far (more than about a foot) from the controller...

...The included terminal blocks are only rated for 16 A, so we recommend soldering thick wires directly to the connector-free version of the board and using higher-current connectors for applications that will exceed the terminal blocks’ ratings

Were these steps followed if required by your setup?

If you are not using these boards, then there could be other possible things to check as well... At this point more information would be
needed to offer more assistance.

I hope some of this helps set you in the right direction...

edit*
ok just looked at the detail specs of this board and noticed

http://www.pololu.com/docs/0J44/4.1

General specifications....
....

Maximum operating voltage:
40 V

Continuous output current per channel:
23 A3

Maximum PWM frequency:
21.77 kHz

Maximum logic voltage:
3.3 V4

Reverse voltage protection?: <------- NO REVERSE voltage protection.
N
....

also

Power for the motor must be supplied to the controller through the large VIN and GND pads. The smaller VIN and GND pads on the left side of the board in the diagrams above are not suitable for high currents and should not be used to power the motor controller. These smaller power pins provide a convenient way to pass the input voltage on to other parts in your system, but they should not be used to power anything that will draw more than 500 mA

and finally

It is not unusual for the stall current of a motor to be an order of magnitude (10×) higher than its free-run current. When a motor is supplied with full power from rest, it briefly draws the full stall current, and it draws nearly twice the stall current if abruptly switched from full speed in one direction to full speed in the other direction.

I'll bet this last one is the catalyst for the anomaly you experience with the order which you turn things on.
X-sim is limiting your acceleration from zero to power on vs turning the motors on w/o x-sim running.
This would be due to incorrect motor settings, which would mean you probably have your motor set with no limits.
Hence the combination of all these things causing massive power spike when you power up and burning up your boards.

Well, it's just my best guess at this time...

[jsmith2307]

Greetings Ale & crs2012,

I'd like to thank you for all of the good info!

Ale, the second attachment is for you! The ground to earth was added after the latest blow up!
crs2012,

Incorrect motor settings in Pololu motor controller software.

I'm not using the Pololu motor control software. Should I?

Incorrect gauge of wiring.

Wire is 10 to 12 gauge.

Note: The power capacitor has a significant effect on performance; the included capacitor is the minimum size recommended, and bigger ones can be added if there is space. A bigger capacitor might be required if the power supply is poor or far (more than about a foot) from the controller...

I've got two 2200uf @ 50 volt caps replacing the 100uf @ 63 volts. I'm using 2 ea wheelchair motors and harness off of the same wheelchair.

What is the amp draw on the motors?
What is the amp draw under heavy load?

I don't know the amperage rating but the wheelchair had two fuses rated @ 25 amps and a circuit breaker rated at 50 amps. I don’t know if fuses are split between the right and left sides. Or, maybe one goes to the onboard charger. See attachment

Incorrect power supply for motors.

the power supply is two 12 volt/55 AH deep cycle batteries, wired to give 24 volts/ wheelchair batteries.

Did you burn 1 board or ALL boards at the same time? This would help to narrow down issues as well.

It was 2 Pololu high power motor drivers 24v23 CS that blew right after flipping the switch!

I'll bet this last one is the catalyst for the anomaly you experience with the order which you turn things on.
X-sim is limiting your acceleration from zero to power on vs turning the motors on w/o x-sim running.
This would be due to incorrect motor settings, which would mean you probably have your motor set with no limits.
Hence the combination of all these things causing massive power spike when you power up and burning up your boards.

I agree with you, with that I've been looking at the Dimension Engineering's SyRen 50 a Regenerative Motor Driver rating @ 100 amps for a very short time!
Once again thank you for input!
jsmith2307

[crs2012]

Howdy! Didn't realize you were in Texas as well... Been hot around here lately...

I'm not using the Pololu motor control software. Should I?

YES! *no

This step is MANDATORY. It reinforces what I've been leading to. *edit this is mandatory for a different board, not the one you use.

http://www.pololu.com/docs/0J44/5.2

The Motor Settings tab of the Pololu Simple Motor Control Center allows you to set up limits to protect your system and lets you specify the details of how your motor should be driven

http://www.pololu.com/docs/0J44/4.1

The first step in using your Simple Motor Controller is connecting power and a motor. With those connections in place, you can immediately start testing with the Simple Motor Control Center
.....

If the motor is likely to be stalled for prolonged periods of time or under heavy load, or if the motor will be rapidly changing direction without acceleration limiting enabled, you should be taking into account the stall current of the motor at the voltage it will be running and selecting a controller that can deliver a continuous current that exceeds the stall current.
.....

It is very important that you select a power source that does not exceed the absolute maximum voltage rating for your Simple Motor Controller. Ripple voltage on the supply line can raise the maximum voltage to more than the average or intended voltage, so we recommend you to select a voltage that leaves at least a 6 V margin for noise. It is also important to note that batteries can be much higher than their nominal voltage when fully charged...
....with 24 V batteries unless appropriate measures are taken to limit the peak voltage.

Pololu 24v23 Simple Motor Controller
Max continuous current w/o heat sink 23A
Recommended max voltage 34V
Absolute max voltage 40V

This is why knowing your motor amp draw is important, no matter what motor controller boards you decide to use.
(Get amp meter and read up on how to use one)

Check the rating of the DC amp meter you are wanting to place in the circuit. It must not be lower in the amperage rating than the circuit you are placing the meter into for measurement. In other words, do not place a 10 amp rated meter into a 30 amp DC circuit, as you will damage the amp meter from a too high of a current through the mechanism

Read more: http://www.ehow.com/how_4810870_wire-amp-meter.html#ixzz2bEayXnO7


Dimension Engineering's SyRen 50 a Regenerative Motor Driver:

Thermal and overcurrent protection:
SyRen 50 features dual temperature sensors and overcurrent sensing. It will protect itself from
failure due to overheating, overloading and short circuits. <----- Seems like this board has better auto protection.

But

I do not know about compatibility with your AMC board /x-sim, or how to configure/program it. That would require trial and error on your part ( these boards are not cheap @ $120+ ea ) So maybe another forum member with knowledge using these boards might be of more assistance here.

The bottom line is... before you continue spending money on any more boards...
Find out what your amp draw from motors are.
THEN
you can determine what motor controller you would need
THEN
make sure you have the motor controller configured correctly for the motors you are using ( using the board's software or hardware PINS )
THEN
continue on with the PID settings once everything is stable.

(edit to remove the parts not pertaining to your pololu boards, after I was corrected on which correct board you are using )

[prilad]

I'm not using the Pololu motor control software. Should I?

YES!

This step is MANDATORY. It reinforces what I've been leading to.
http://www.pololu.com/docs/0J44/5.2

The Motor Settings tab of the Pololu Simple Motor Control Center allows you to set up limits to protect your system and lets you specify the details of how your motor should be driven

@crs2012

No, crs2012, you're wrong... As I see jsmith2307 used Pololu 24v23 driver (without USB connector). Not Simple Motor Controller. And he physically can't to use Pololu Simple Motor Control Center


@jsmith2307
Connecting diagram is right. But I can't see where is "power switch". You wrote

If I flip the switch to the simulator first, then I hear a pop,

Can you build diagram with all power supplies and switches? How you power your AMC board?

[crs2012]

Thank you for correcting my mistake... I edited my previous post to remove reference to wrong board.

You are correct, I missed 2 Pololu high power motor 'drivers 24v23 CS '<---- detail...

I was half asleep when I responded earlier.... Ignore the motor driver software I mentioned earlier, that was for a different board....

I see the board is...

http://www.pololu.com/catalog/product/1456/resources instead...

Warning: This motor driver has no over-current or over-temperature shut-off. Either condition can cause permanent damage to the motor driver. We recommend you use the current-sense output CS to monitor your current draw if your application will put the driver close to its limits of operation.

This board still has the same potential issue as other board. When you power up the motors first before the software(x-sim), you have no HARD limit set for motors (this board does not have ability to set with software like the Simple High-Power Motor Controller 24v23), and without knowing how much amps they draw when started, we still cannot determine if the amp spikes are out of range for these boards as well.

So you MUST limit amp spikes from power supply/batteries, IF the motors are indeed spiking amps that exceed the limits of the boards. Using these driver boards, this is not easily achieved as it requires special wiring/electronics between power supply and boards. The easiest solution is to use a power supply that is not capable of exceeding the limits of the boards. OR, using motors not capable of drawing amps exceeding the limits of the boards. OR, changing boards which ARE capable of handling a much higher amp spike.

Because there is no internal temperature limiting on the motor driver, the entire system should be designed to keep the load current below the 23 A limit.

IF, the motors are well under the operating Amp limits of the boards you are using, then you would need to try diagnosing deeper into other possibilities.

Hope this helps bring you closer to solving your board melting issues.

[prilad]

Hi guys.

I think this problem may be solved by placing two pull-down resistors ( from 1K to 10K, one for every PWM lines) between PWM line and GND.

This will hold the line PWM at a low ("zero") level until the end of the microcontroller initialization.

And I want to ask jsmith2307 - how many PWM inputs has your Pololu? Two (PWML and PWMH) or one (PWM)?

[jsmith2307]

Greetings,
Ale, I've got both PMWH and PWML. I only use PMWH.

I think this problem may be solved by placing two pull-down resistors ( from 1K to 10K, one for every PWM lines) between PWM line and GND.

On the heat bridge side or the avr 1.6 or both?

crs2012,

Find out what your amp draw from motors are.
THEN
you can determine what motor controller you would need
THEN
make sure you have the motor controller configured correctly for the motors you are using ( using the board's software or hardware PINS )
THEN
continue on with the PID settings once everything is stable.

I'll do this!

jsmith2307