Surely it is not loose. It was damaged somehow. But interestingly there is a voltage change on stepping (if selected) although stepper is not moving.
Anyway, thanx for your help.
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Surely it is not loose. It was damaged somehow. But interestingly there is a voltage change on stepping (if selected) although stepper is not moving.
Anyway, thanx for your help.
leaveme,
Your comment about there being some activity on the line got me thinking about LPT history I read somewhere ( like here http://www.beyondlogic.org/spp/parallel.htm ).
one final thing to check; lpt pin 1 will be open collector driver with pullup resistor in the pc if the bios is programmed to original standard mode. the LPT pin 1 may be actively driven high if mode is changed (I think) to EPP or ECP. what LPT mode is your PC bios set to ? Can pin 1 be driven properly if you change to a different mode than you are using now ?
lasik2025
I would not bother buying one of these chinese cards again. I bought a 4 axis and 5 axis card. I first connected the 4 axis card to my nema 23 269oz/in steppers. It worked well for about 3 hours and then the y-axis was fried. I connected the 5 axis to test it and only connected the z, a and b axis to test them. The x-axis fried itself with it disabled in Mach3 and with no stepper connected to it. I though well, it is burnt I will keep testing the other axis. As the board was lying behind my monitor it was out of my view when working on my computer. I suddenly heard the sound of something burning and looked around my monitor to find the board on fire. There was some type of oily stuff coming out of the th6560 chip that was burning with flames. Be warned! These are not worth what ever you pay for them. Lucky I have no damage to my computer.
Cheers
Piet
It will be fried if you run the board with more than 28v. Safe selection is 24v.
What voltage you are running?
Thanks for your reply.Quote:
Originally Posted by leaveme
My PS set at 20V as the documentation I received with it states:
2-16V DC power supply for Nema 17 stepper motors
16-24V DC power supply for Nema*23 stepper motors
24-36V DC power supply for Nema*34 stepper motors
Cheers
Piet
The design of CNC controller matters, we need to figure out which is the best way to get the good performance, some China controllers are using Japanese I/C and UK CPUs.
Hello,
I have a similar board as this, the 3axis version of this board, since I received it I have tried different thing to fix a non working X axis, the Y and Z are working perfectly but not the X.
a couple thing I have noticed is both regulator are extremely overheating even without motor operation, they are heating to the point I cant even touch them.
another issue I noticed is the IC enable is not driven properly on the defective axis if I do a bypass and send 5v to the IC enable pin the motor start working properly but make noise.
I will atempt your fix on the IC enable input to see if it fix the issue.
I changed theTB6560 chip as I tough it was the problem but I still have the same result, do you have an idea what could cause this and why the regulator are overheating even with the fan not connected.
What voltage power supply are you using?Quote:
Originally Posted by telah
I have one of these boards, with a 24-volt power supply. I have not yet hooked mine up, but looking at the schematic it appears that the 5-volt regulator is powered by the output from the 12-volt regulator, which in turn is powered by the 24-volt supply.
So, even if the fan is not running, the 12-volt regulator is supplying current to the 5-volt regulator and the circuitry that it powers. So the key to figuring out why they are getting hot even without the fan running would be to figure out how much current the board is drawing for the logic circuits (not including the motor drive current, of course, because that comes directly from the power supply).
The following back-of-envelope calculation could be completely wrong, so don't hold me to it:
I don't know how much current each TB6560 is drawing (I looked at the datasheet, which led me to believe that it might not be a whole lot, but I'm not sure). There is not a whole lot of other stuff on the board that looks like it should be drawing current, aside from the LEDs and optoisolators and perhaps the 74HC14s. (I'm not sure whether the relay would normally be energized or not).
On a 3-axis board, counting up all of the LEDs and optoisolators gave me almost 20 devices. I'm guessing that the LEDs and optos may each draw something like 5 ma or 10 ma, for a total of perhaps 100 to 200 ma. The 74HC14s have a maximum draw of 50 ma each (if I have read the specs correctly), but they are probably drawing less than that. So that probably gives a range of somewhere between 150 ma to 300 ma for the 5-volt devices (but in reality you might want to decrease those assumed current draws if the board is sitting idle with most of the devices off or quiescent). A 4-axis board might draw a bit more.
The 12-volt regulator is dropping 12 volts from the input supply voltage, and if it is supplying 150 ma to 300 ma, the regulator could be dissipating something like 2 to 4 watts even without the fan running, which would explain the heating. The 5-volt regulator is dropping 7 volts which means that it could be dissipating a watt to a watt and a half, which would also heat it up, although not as much as the 12-volt regulator.
My current thinking is that I should at least provide the 12-volt regulator with a separate supply from the one that is powering the steppers, so that at least that one is not dissipating so much power. I could also separate out the input to the 5-volt supply and give it its own wall wart. Or I could also put a fan on the regulator heat sinks.
telah,Quote:
Originally Posted by telah
circuitz found shorted traces on his 3-axis board that may be contributing to the power load on the regulator; see http://www.cnczone.com/forums/820437-post17.htmls
also, the regulators do get hot to the touch but are rated at very high operating temp. On my board, I measured 155 F (68C) with fan, 135 F (57C) without fan but the regulator itself can operate to 150 C which converts to 300 F which is way too hot to touch (from LM7812 spec found online Top).
lasik2025
Quote:
Originally Posted by lasik2025
thanks both for your reply, the link doesn't seem to be working but i'll do a search on the forum.
I will do more testing this week and come back with the result.
I am using a 24v 10a power supply you can see my mach3 config in the screenshot.
Lasik, what dip settings are you using ? I am currently set to 75% current, Fast decay and 1/2 microstep.
Regards