it worked for 5 seconds then it stopped, the led on the driver is on but the ship gets very hot. I turned the dial before turning everything on at about 3/4.
It’s driven by an arduino, and for 5 seconds I was able to correctly control the speed through serial.
Now I don’t have a clue if the stepper died or if it is the driver; and for what reason.
(the driver is correctly powered though). everything seems correctly wired, I didn’t change any jumper configuration (I have just 2 pins connected + ground).
What I could have done wrong is not use a heatsink (but it’s supposed to be protected), and also I unplunged the power supply several times with the arduino sketch still sending data to the driver, but I didn’t think this could be a problem.
the power supply is a repurposed 12V / 2A hard drive power supply.
Is there a way to know which of the driver or the motor is dead, and to avoid this for happening again if I try this again? (takes about 2 weeks to receive pieces here, this is really frustrating)
thanks for your help
(edit: sorry for double post, didn’t understand there was moderation the first time)
It sound to me like you are not bothering to research how to use this equipment, and just jumping in. For example, what is the following supposed to do?
I turned the dial before turning everything on at about 3/4.
What dial? If you are trying to adjust the winding current limit, this is certainly not the right approach. That is a low voltage, high current motor, and it is ESSENTIAL that you adjust the current limit properly.
It is not so easy to damage the motor, but you can easily destroy these drivers. The best way to destroy them is to disconnect the motor leads while powered up. Another popular way to damage boards is to send signals to them while they are unpowered.
thanks for your answer, reading the manual I realise I wasn’t aware there was a formula to get the exact power, and the version 1.2 sold by sparkfun can output up to 5A, so if I did set it too high maybe that’s what fried the motor.
I thought 2A was the maximum I could get out of the driver.
this is clearly how it’s explained in this link given by sparkfun which I blindly followed (I set it a bit below max, but still)
I did make the test with the TP1 lead explained and I got the 1,76V corresponding to 2A about halfway.
it’s the first time I’ve a stepper but the movement seemed really twitchy.
does the fact that I could do this test after the failure mean the driver chip still works?
the leads to the motors were soldered but I did cut the power several times to the driver while still sending signal to it, though it stopped working after trying to push the speed.
is there any way to test the motor without the driver?
Ignore the advertising claims; it is almost impossible to get even 1.5 amperes out of the A4988 chip in the Big Easy Driver without using a heat sink, as it will overheat and shut down. Also, it is almost impossible to destroy that motor using a 12V/2A power supply, as the power supply will limit or shut down.
Keep in mind that the motor winding resistance is about 1.5 ohms and if connected to a sufficiently beefy 12V power supply it will draw 8 amperes/winding in unipolar configuration, or 4 amperes/winding in bipolar configuration (3 ohms). To check the motor, use a multimeter to verify those resistances.
It is certainly possible that the driver has been damaged. However, if not, it should work with that motor. I suggest to follow the directions carefully to set the winding current to be about 1 ampere in full step mode, using the bipolar configuration. Then test the driver at a low step rate.
Let us know how it goes, as there are some motors for which the winding inductance is too low for the A4988 to function properly.
well no luck, I tried setting 1 Amp and tying MS1/MS2/MS3 to ground to get the full step mode, and I have indeed 2 pairs of leads with about 3 ohms on each pair (which means it’s bipolar right?). even if there is no control signal I should hear a noise when the driver is plugged in right? the fact that it suddenly stopped working the first time tells me something’s broken.
The driver may be damaged; almost certainly so if the motor leads were disconnected while it was powered up.
Also, the driver may be susceptible to voltage spikes from the power leads. Read the caution about this on the Pololu product page for their version of the A4988 driver: https://www.pololu.com/product/1182
It is a good idea to put a 100 uF capacitor across the power leads, close to the driver board, as shown on the Pololu page above.
Hi, i make the same connection like grrrz do whit the same result. The motor work for 4 o 5 seconds and then i shut down the power. wen i try to repeat nothing work but the big easy driver chip turn the led on but mottor not work
I use arduino uno r3, the big easy driver and the same PAP motor. As power supply i use an ATX power from a pc of 400w using yellow wire 12v 17A. hahaha i dont have much idea about all this im learning but the problem is i cant found any schema were i can see how to connect all this.
Can you give us a link were we can see how to connect all this and work fine? Becouse i confuse… the motor specification say it work at 3v and the big easy driver say it can manage 8 to 35v and its out of range. maybe we need other driver to control this motor???
Thanks!!!
Sorry about my english but its not my mother languajes!!