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The problem will be when the power will come back! Not at power loss there will be no power present! Both switches will be on simultaneously though and the powerup sequence will be violated. For that reason I designed the circuit above!Quote:
Originally Posted by ehtisham-syed
I got 2 of these in the shop, funny mine is working perfectly bolt-on directly last two years ago and it`s up and working until now, with this as a spare, so what`s the difference about my board and the OP`s board? it worked perfectly on a 24VDC power supply, one thing for sure LM78XX IC`s are rated 32VDC max not 36VDC.
http://www.cnczone.com/forums/attach...d=371494&stc=1
You are in LUCK!Quote:
Originally Posted by KH0UJ
The whole issue of smoked ICs comes from the fact that the designers of the board did not follow the recommendations set by Toshiba for the powerup and power down sequence.
There are other minor design faults but this is the one that leads to 6560 failure.
Hi Guys. Here is some tips for users of the TB6560 stepper motor driver:
Make sure your pulse signal duration is around 10% of the time between pulses. If you use a 555 timer or a signal generator with 50% duration and you notice the motors do not have good torque or limited speed the pulse duration is the problem. Mach 3 normally outputs a narrow pulse.
Also when powering up the driver, make sure the disable signal is on before the power is applied to the driver. This is the power-on sequence recommendation from Toshiba.
If you want to optimize the performance of your driver, consider at least the schmitt trigger between the opto-coupler and the driver clock input and if there is the torque reduction circuit, it should be removed.
hi guys. i have a tb6560ahq 4 axis.all of mach3 configuration is true.but y axis is not working.the y led is lighting but stepper is stoped.
Wow, I have only just found this, now 10 year old thread if immense TB6560 knowledge.
I’m glad I have though as I bought a CNC water jet table that has been rebuilt using this driver board. The board that is in it isn’t working currently. It appears that some of the capacitors and FB307 diodes got too hot. I have a new board on the way but I’m also working through the current board with a multi meter and replacing what I can find that’s bad si I have a backup board.
This thread is going to be a huge help....
So having read through some more of this thread (sorry, I've done the book report version so far and read about the first 10 pages and about the last 7 or so) and hoping that some of the original contributors are still monitoring this.
If or should I say, inevitably, when this new board I have coming blows smoke, how easy will it be to replace this with the Gecko G540 controller? Should I stup up for the whole kit? It looks like the Gecko runs at 48V where as the current board runs at 24v.
Though it looks like the motors I have could take it. I have the KL23H286-20-8B steppers.
It looks like there are a few versions and I don't know what would be best. My table is 7' x 12'. the bed and rail frame are steel but the gantry is aluminum.
I can provide pics and info for anything specific you may ask.
did you ever have the machine working ?
looking at the motors data sheet
Attachment 438490
https://www.automationtechnologiesin...H286-20-8B.pdf
G540 pdf
Attachment 438492
I would set the G540 motor current to 2.8A and see if the motors work OK on your machine
the motors inductance with the coils wired in parallel is higher than I would like 6.8 mH instead of about 2.5 mH
using the rule of thumb on page 3 of the G540 manual
32 x square root of the inductance = optimum driver supply voltage
a motor with a coil inductance of 2.5 mH needs the driver supply voltage to be
32 * (?2.5) = 50.6VDC
a motor with a coil inductance of 6.8 mH needs the driver supply voltage to be
32 * (?6.8) = 83VDC !!!!
( note the G540 supply limit is 50V )
reducing the supply to 50V limits the maximum speed you can step
John
I receive the new blue board and parts for my old board today. I'm going to look over this thread again before plugging the new board in to be sure the settings are correct.
Right now when I plug my old board to the power supply the power supply shuts down, so there's something on the board that it doesn't like. Right now I have changed out the large capacitors as at least one of them had burst and some of the diodes by the lower green connections are bad so I'm going to change them today but I'm not sure that they will be the cause of the short??
My motors are wired in series, I'm at best a noob with electronics but when I tested the motors with my multi meter I was getting a 6 ohms reading so that's how I found that out.
My power supply is only 24V - 6.5 amp. That sounds pretty under rated per your calcs above
How is changing how my motor is wired going to help?
Like I said, I'm very green with electronics.
Thank you for your reply!
So my new board arrived and it is noticeably different and yet the same. I'm hoping that they have taken care of many of the problems that have hampered many of you in the past.
Here are some pics for you all to look at and compare. If you need any specifics on the components, I'll try to help you out until it's installed.
Did you get a manual with the new board so you know if you can set the current to 2.8A ?
and do you have the manual for the old board to see what the motor curren was set to ?
the TB6560 IC used on the board is going to limit your supply voltage to 24V
its not clear from the photos what value of the 8 resistors used on the 2 boards to monitor the motor current are
its not easy to see what colour the bands on the resistors are
knowing the colours of the bands the resistor value can be decoded
depending on the version of TB6560 used
TB6560AHQ: 3.5 A (peak) R sense 0.15 ohms ?
TB6560AFG: 2.5 A (peak) R sense 0.2 ohms ?
with the coils wired in parallel you need to set the motor current to 2.8A -
this has the advantage of the inductance being 6.8 mH so you will be able to step the motor faster
with 3 axis you may be able to get away using the old power supply
but I would replace it with a new 24V 10A power supply
with the coils wired in series you need to set the motor current to 1.4A
the down side the inductance rises to 27 mH
John
Mine is the AHQ chip set, 3.5amp. I do not have the manual for the new board and have just sent a message to the seller as it is supposed to be included on cd.Quote:
Originally Posted by john-100
All 4 axis are wired but there are only three, x - up and down the table, y - across the gantry and z to raise and lower the torch though I’m not sure if the x axis is being run from one or if C is running it in parallel with x.
Don’t the motors have more torque in series? The gantry on this table is 9’ long. I suppose it’s something I’ll need to play with. I’ll just be happy to get it fully functional before I start changing anything.
Another mod I might make in the future is to change it from running in belts to gear driven but I know that will open up a whole new bag of worms.