Nema 23. Slow

arvidb wrote:

Power (watt) = Voltage (volt) * Current (ampere). So yours is 24 V * 8.3 A = 199 W, and the Probotix one is 24 V * 6.5 A = 156 W.

In short: a higher voltage lets you run the same machine at a higher speed, but you also need to have enough current available to be able to "use" the voltage. If you are happy with the strength of the machine at low speeds today, and just want it to go faster, you need a higher voltage at (at least) the same current.

Of course, make sure the machine does not bind, and that all connections are correct, before buying something new.

What I was trying to figure out is why is my setup is considered under powered and the Probotix is not. There power supply is 50 watts
under mine and there machine works OK .

So mu question is to move along the X-axis 10" takes how long on an average machine. Using the jog button in Stepconfig.
If you start stepconfig and go to X-axis and use the jog button arrow what time do you get for 10" of travel. When I know this
I will have an understanding of speed.

Thank you

jaredts wrote:

Did you say that you were programming your machine to go 5", and it actually moves 10"? If so you are actually getting twice the feedrate that you are reporting. I think you said that your microstepping in stepconfig was at 4, but I would check that as I don't think that is an option on the board you are using (start with 1/2 step until you get everything worked out and then experiment with more microstepping if you want). Are your motors 4 wire or 6 wire? If they are 6 then wire them half coil for best speed. What max. current setting are you using on your driver board?

No. I was told the first thing I needed to do was get the machine to move 1' when it is told to move 1".I worked on this
and have it set to move 1" or 5" or 10".

The motors are 6 wire. I have green and black paired, red and blue paired, white and yellow not used. I did this by testing
resistance to match pairs. The microstepping I can use so far is 1 or 2 nothing else works.
when you say half coil do you mean the high resistance side. I will explore this and see what happens.

The jumper pins are set right now for 100% current. Should this be different.

Thank You

The information I find for your motor says 1 amp/phase. I find that very hard to believe as it is extremely low, but if that is correct your driver board should be set at a max current of .7 amps/phase (as your motors are wired now). If you rewire them half coil you should be able to set your board at the max unipolar current of 1 amps/phase--and will get a much better torque curve with higher top speed and only a small sacrifice of low end torque. For half coil: A+=black, A-=yellow, B+=red, B-=white (green and blue unused).

You may try turning the current down on your board before changing anything else and just see if the motor runs more smoothly. In my experience, which isn't all that much, a stepper motor pushing nearly 300 oz/in. holding torque usually pulls around 2.5 to 3 amps/phase give or take, so the 1 amp number does sound off to me. If 1 amp is correct than your power supply is more than enough amps for your system.

MakingToothpicks wrote:

So mu question is to move along the X-axis 10" takes how long on an average machine. Using the jog button in Stepconfig.
If you start stepconfig and go to X-axis and use the jog button arrow what time do you get for 10" of travel. When I know this I will have an understanding of speed.

Well, I cannot answer for the average machine. I think the speeds vary a lot. For a low-power, stepper based machine with threaded rod as a lead screw, I would say that 10 seconds for a 10" move sounds OK. That's 60 inches/minute. With a normal M10 rod as lead screw, that corresponds to just over 1500 RPM on the motor, so perhaps it's a bit optimistic, but you should definitely reach half of that (i.e. 30 inches/minute, or 20 seconds for a 10" move).

Your power supply should have more than enough power to reach that speed with only a single axis moving. (Not sure about multi-axis moves.) It may be that its voltage is too low for the motors you have though, or the LinuxCNC settings may be wrong. You really do need to understand the settings in the config.

I see in your first post that you had "Stepconf at 200 for speed". If this is inches per minute, and your machine is using ordinary threaded rod, then this sounds quite high, and your motors may be missing/skipping most of the steps.

When I know this I will have an understanding of speed.

What is most important IMHO is that the machine can move reliably at the required work speed.
If you are drilling or milling in say steel your work feed rates will be slow, if however your machine is a high powered plasma cutter cutting thin material it will need a much faster feed rate.
A router cutting wood would fall somewhere in between.
The required feed speed on a router/mill is normally based on chip load, mill diameter, spindle rpm, material, etc. You can look at feed charts or the formulas to calculate the speed you will need for the work you intend to do.


Rick G

I appricate your on SS , so go for a PSU which is within your budget 24v @15A should be fine .
looking at your hal file , i'd suggest your default max accelleration and velocity settings appear low

see attached files which may complicate even more , as the pinouts are different to yours
( this is a problem with tb6560's theirs so many different boards out there ! )


anyhow see how you go , and i'll help you through , but if you can either send me the manual for your board , or locate the version number it would help

Dave

jaredts wrote:

The information I find for your motor says 1 amp/phase. I find that very hard to believe as it is extremely low, but if that is correct your driver board should be set at a max current of .7 amps/phase (as your motors are wired now). If you rewire them half coil you should be able to set your board at the max unipolar current of 1 amps/phase--and will get a much better torque curve with higher top speed and only a small sacrifice of low end torque. For half coil: A+=black, A-=yellow, B+=red, B-=white (green and blue unused).

I did the rewire. I see a big improvement. Thank you.

Well, I cannot answer for the average machine. I think the speeds vary a lot. For a low-power, stepper based machine with threaded rod as a lead screw, I would say that 10 seconds for a 10" move sounds OK. That's 60 inches/minute. With a normal M10 rod as lead screw, that corresponds to just over 1500 RPM on the motor, so perhaps it's a bit optimistic, but you should definitely reach half of that (i.e. 30 inches/minute, or 20 seconds for a 10" move).

I see in your first post that you had "Stepconf at 200 for speed". If this is inches per minute, and your machine is using ordinary threaded rod, then this sounds quite high, and your motors may be missing/skipping most of the steps.[/quote]

That is what I was looking for. What does an average machine not cutting anything move. 1 inch per 1 sec. Now I can see what I can get to.

Thank You

Hello all. I am back after much work on the machine. I have the X and Y motors working. I am still stuck on Z.
On the control board I can measure volts at the Xb- to Xb+ and Yb- to Yb+ I get about 24 volts, At Zb- to Zb+ I
get -21.5 Volts. the polarity is different and the volts are lower.

The Pins in use to make X and Y work are 1 , 2 , 4 , 7 , 14 , 16 , and 17 leaving 3 , 5 , 6 , 8 , and 9 unused.
The pins that are supposed to make Z work are 3 step , 5 enabled and 6 Dir. This does not work. I have tried
using different step and Dir pins so far nothing. I do get the motor locked up and very hot so I need to stop.
Pin 5 needs to be enabled or I get no volts at Z.

Any Ideas ??

Thank You
Don

i'm guessing you may have a faulty stepper driver ..especialy as the voltages you have measured are different on the z and you say the motor is hot
although it is quite normal for steppers to be quite warm to touch and give the impression of a fault , remember stepper motors are energised also at the stationary point , hence why they run hot

are all your motors the same ? i.e the wiring is identical between them all ? i'll presume they are .

try swapping the stepper motor wiring from the z to say drive x and see if the motor runs ok . if yes then I would say the z stepper driver is faulty
check the dip switch settings for the z axis and make sure they are correct ..