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TB65603A Single Axis Stepper Motor Driver Board (HCMODU0022) 
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Joined: Wed Oct 28, 2015 7:58 am
Posts: 3
Post Re: TB65603A Single Axis Stepper Motor Driver Board (HCMODU0
Thank you very much for this prompt response.

[1] Running current is indeed 2.1 A so I've set 2 A - if I don't get quite enough torque I may go to 2.4A since my duty cycle will only be about 30 seconds ON / 12 hours OFF and I doubt that will overheat anything.

[2] If there is a minimum pulse width I agree that mark/space is probably unimportant.

[3] The 78M05 regulator is on the board and I had intended to steal my 5V supply from it if I could not use the 15V supply directly. But the 4093 should not really be called on to deliver 10 mA so I'll add a PMOS and a 1 kΩ resistor to drive the isolator (10 kΩ would limit the current to about 1.3 mA, which might not be enough) and run the lot on 15V.

[4] The 60 is because rpm is revolutions per minute, whereas Hertz is cycles per second. So rps will be (f/2) / 200 - it is indeed a 1.8 degree/step motor. I shall run it at 2 rps with an 800 Hz drive. If I use 50 μS pulses this is a duty cycle of only 4% so the mean current to the 4093 and its MOSFET will be an insignificant 500 μA or so.


Thu Oct 29, 2015 2:40 pm
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Post Re: TB65603A Single Axis Stepper Motor Driver Board (HCMODU0
Quote:
[3] The 78M05 regulator is on the board and I had intended to steal my 5V supply from it if I could not use the 15V supply directly.

I'd advise against this anyway, you'd risk blowing the regulator which would put 15V onto the 5V rail.

Quote:
10 kΩ would limit the current to about 1.3 mA, which might not be enough


Sorry that was a typo, I meant to say 1K. That should limit it to about about 10mA of current taking into account he forward voltage of the LED and the fact there is alread a 300R resistor in series.

Quote:
[4] The 60 is because rpm is revolutions per minute

Of course! I was thinking your motor had a gearbox. Just having a dumb moment :-)

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Thu Oct 29, 2015 3:46 pm
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Joined: Wed Oct 28, 2015 7:58 am
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Post Re: TB65603A Single Axis Stepper Motor Driver Board (HCMODU0
Thank you for the further inputs. You say

Quote:
I'd advise against this anyway, you'd risk blowing the regulator which would put 15V onto the 5V rail.


I really doubt that a few hundred μA load on this regulator is very likely to damage it (sure, there are going to be 10 mA pulses but the mean current is <<1 mA and there's 220 μF decoupling).

I routinely steal small currents from regulators in equipment to power a mA or two of extra gadgetry and I've never had any trouble doing so.


Fri Oct 30, 2015 12:20 pm
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Post Re: TB65603A Single Axis Stepper Motor Driver Board (HCMODU0
It's simply as a company we can't recommend using a product in a way that wouldn't be covered by the warranty. It's a problem we see from time to time and for some products we actually send out a slip with the product warning not use internal regulators to power external electronics.

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Sat Oct 31, 2015 10:28 am
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Joined: Thu Nov 26, 2015 9:13 pm
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Post Re: TB65603A Single Axis Stepper Motor Driver Board (HCMODU0
Hi Guys,

So I bought a couple of these stepper drivers and I just have a few questions:

1. I've seen loads of these from different manufacturers (mostly chinese); who is the original manufacturer? And would it make a difference performance-wise if I bought the one from hobbycomponents (preferable) than one from China?

2. I can't really tell what the difference is using the HCmotor library or just writing the code to pulse the motor myself; e.g. using examples from here; http://www.schmalzhaus.com/EasyDriver/E ... mples.html. Is there something the HCmotor library makes easier? Can it accelerate the motor?

3. Finally, it was mentioned in an earlier post that if I supply 12V to the driver, it should supply 12V to my motors right? I'm not an electrical engineer but I measured the voltage to my motor by placing the black multimeter probe on the screw for the GND terminal, and the red probe on either the A+ or B+ terminals. I get only about 5 to 6V using a 12V power supply and about 7 to 8V using a 24V power supply (correct me if this is the wrong way to measure the voltage).
I'm wandering if this is the reason my motor is only moving at 3rpm when it should be moving at 25rpm p.s. this is the motor I am working with; [LINK REMOVED BY ADMIN (Please see section 5.2 of forum terms and conditions)]

Any help would be much appreciated.

Thanks!


Thu Nov 26, 2015 9:38 pm
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Post Re: TB65603A Single Axis Stepper Motor Driver Board (HCMODU0
Quote:
1. I've seen loads of these from different manufacturers (mostly chinese); who is the original manufacturer? And would it make a difference performance-wise if I bought the one from hobbycomponents (preferable) than one from China?


There is more than one manufacturer for this controller. They are mostly based around the same reference design with a Toshiba TB6560 at the centre. They will mostly work in the same way and the only significant difference between one manufacture and the next is the quality of manufacturing. With regards to buying it directly from China there are many other factors to consider. We could probably write an essay on this but it would be off topic to post here but I can pick one of the main reasons which is support. If the seller also sells iPhone cases and and e-cigarettes they probably not going to be very helpful if you have a technical problem with a stepper motor driver.

Quote:
2. I can't really tell what the difference is using the HCmotor library or just writing the code to pulse the motor myself;


Part of the reason why we wrote the HCMotor was to help customers who mainly want to speed control a motor from a potentiometer but have little or no programming skills. The library was written to cover both DC and stepper motors with more than one type driver and it does all this in the background leaving your main loop free. The TB6560 does takes care of a lot of the complicated stuff so if you know what you are doing and your application isn't very complicated then you can just write the sketch yourself.

Quote:
3. Finally, it was mentioned in an earlier post that if I supply 12V to the driver, it should supply 12V to my motors right? I'm not an electrical engineer but I measured the voltage to my motor by placing the black multimeter probe on the screw for the GND terminal, and the red probe on either the A+ or B+ terminals. I get only about 5 to 6V using a 12V power supply and about 7 to 8V using a 24V power supply (correct me if this is the wrong way to measure the voltage).


Driving a stepper motor is a little more complicated than a DC motor. With a DC motor you can just simply apply a fixed voltage across the motor to turn it. With a stepper motor there is more than one coil and each coil must be pulsed in a set sequence. What's more the TB6560 (or similar) is controlling the motor in a current mode, not a voltage mode. If you where to look on an oscilloscope you would not see a constant voltage, instead it would be rapidly stepping up and down. So a standard multimeter will not give you a correct reading.

Quote:
I'm wandering if this is the reason my motor is only moving at 3rpm when it should be moving at 25rpm


There could be more than one reason for this including a bad connection to one of the coils but it could simply be the excitation mode that your driver is operating in. In some modes the driver can make partial steps per clock pulse resulting in requiring several pulses per step. Does the motor turn smoothly? If not it could be a bad connection or coil. If it does it could be the mode you have the driver configured too.

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Fri Nov 27, 2015 9:39 am
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Joined: Thu Nov 26, 2015 9:13 pm
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Post Re: TB65603A Single Axis Stepper Motor Driver Board (HCMODU0
Thanks for your replies.

I know the connection is ok. I've tried different power supplies (12V and 24V), I've tried accelerating at different accelerations; slow and fast, I've even tried "more powerful"/more expensive drivers but I still get the same result so I don't think it's the drivers.

Anyways, the motor I'm working with is the 3334_0 phidgets bipolar geared stepper motor. If anyone has managed to get it working at it's max speed of 25rpm (given by phidgets), preferably using the tb6560 driver, I'd appreciate it if you post in detail how it was done. I'll do the same if I manage to get it working. In the meantime I'm gonna have to make do with 3rpm :-S

Thanks.


Fri Nov 27, 2015 9:33 pm
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Post Re: TB65603A Single Axis Stepper Motor Driver Board (HCMODU0
I've taken a look at the spec for your motor and although it does have a tiny step angle both an Arduino and TB6560 should be able to drive it at 25 RPM. The only other two things I can suggest is to check what excitation mode you have the TB6560 set to (switch SW3 and SW4) and if that's not the issue the following modified blink sketch. Assuming your using a ATMega328 based Arduino it should turn your motor at about 10 RPM with the excitation mode set to 1:

Code:
/*
  Blink
  Turns on an LED on for one second, then off for one second, repeatedly.
 
  This example code is in the public domain.
 */
 
// Pin 13 has an LED connected on most Arduino boards.
// give it a name:
int led = 13;

// the setup routine runs once when you press reset:
void setup() {               
  // initialize the digital pin as an output.
  pinMode(led, OUTPUT);     
}

// the loop routine runs over and over again forever:
void loop() {
  digitalWrite(led, HIGH);   // turn the LED on (HIGH is the voltage level)
  delayMicroseconds(182);             
  digitalWrite(led, LOW);    // turn the LED off by making the voltage LOW
  delayMicroseconds(182);             
}

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Sat Nov 28, 2015 9:54 am
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Joined: Thu Nov 26, 2015 9:13 pm
Posts: 3
Post Re: TB65603A Single Axis Stepper Motor Driver Board (HCMODU0
That's pretty much the code structure I'm using and I have actually tried a slightly lower value before. I've never managed to get anything to work with an excitation mode of 1.

But anyways I've made some progress with the problem:

The tb6560 will not be able to run the motor in excitation mode set to 1/16 because it's not fast enough (I've tried) but theoretically it should be possible to run it in 1/8 and below (I will try later).

The motor is unlikely to run at 25RPM without accelerating it using an ideal acceleration (not too fast).

So basically the key is in selecting the right excitation mode and the right acceleration. I have managed to increase the speed to about 13RPM using faster drivers at 1/16 step mode but I will try the tb6560 at lower step modes. Hopefully the theory will prove to be practical :-D

Thanks.


Sat Nov 28, 2015 5:21 pm
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