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steppernewbie
13-02-2018, 08:34 PM
Hi
I have bought a kit with a Nema24 motor and driver M542T and a MPG wheel and 36v power supply in an attempt to learn how I can use steppermotors for different things. I am not an complete newbie to electronics but many components I do not know how works, so not to burn of my new gismos I have some questions.
I do not want to use them in CNC machines but just to move things in a precise distance, like the Z axis on my milling machine (fitted with DRO) with the least amount of components and without the use of CNC software.
And here is my question. In the manual for the driver M542T it says that it can accept Line Driver Signals on Pul and Dir ports and I found on the internet a Tosoku MPG with 6 connectors like the one I have, so am I supposed to connect my MPG to the driver (I hope you can see the the writing on the MPG) like this, on MPG A to driver PUL+, MPG A (with line over) to driver PUL-, on MPG B to driver DIR+, and on MPG B (with a line over) to driver DIR-.
I this is correct and working, then my next question is, is it possible to multiply the signals from my MPG like remote MPG pendants for CNC machines with a switch for x1, x100 and x1000 so that x1 is my MPG without multiplying and a switch that switches my MPG signal over to 2 gizmos for x100 and x1000 if you know what I mean.
Kind regards
Steppernewbie

magicniner
13-02-2018, 09:26 PM
Sadly for you the free version of Mach3 will do exactly what you want through the MDI interface but you're dead against CNC software.
Good day,
Nick

steppernewbie
13-02-2018, 10:29 PM
Hi magicniner
Maby I should not have asked, Sorry for treading on some CNC toes
I am not dead against CNC software, my machine (Optimum MB4) is just not a CNC machine, and if you google DIY Motor for my Z axis or something like that, you will find all kinds of solutions for my type of machine with hand cranked Z axis where the DRO is installed and also a quill), I just would like a motorized precise way of operating my Z axis (if possible) with locked quill, because using the quill is just introducing another wobbly factor to a not already super sturdy machine.
Forgot to say that hand cranking the Z axis is difficult for me because of fycical challenges, I got a motor on it already but I cant stop it percisely where I want.
Kind regards
Steppernewbie

magicniner
13-02-2018, 10:52 PM
I got a motor on it already but I cant stop it percisely where I want.

I'll let someone else explain how to run and stop a stepper motor precisely where you want, but you won't like it :D

steppernewbie
13-02-2018, 11:02 PM
I was hoping I could run and stop (control) it with my MPG, but if the answer to my first question about connecting the MPG to the driver, is that it canīt be connected, then I maby have a cheap stepper kit for sale.

magicniner
13-02-2018, 11:08 PM
You can connect an MPG to a Motion Controller, there may be drivers that will accept an MPG but exactly how did you expect to set/program a stop point with an MPG and no programming?
You do know what MPG stands for?

m_c
13-02-2018, 11:41 PM
If all you want is to move the Z axis manually via the MPG and driver/motor, then what you're looking for is a step multiplier.
It's not something I've looked at for quite some time, but the easiest option is to probably just program an Arduino for the task. Count the pulses from the MPG, then multiply by X and output them.

As for the line driver signals, just connect the - to gnd on the driver, and leave the _ terminals on the MPG disconnected. For something this simple, I wouldn't bother using line drivers, as it'll just add an extra layer of complexity for no practical gain.

steppernewbie
14-02-2018, 03:09 AM
Hi m_c
Thank you for your answer.
If my MPG (Answer to magicniner : A Manual Pulse Generator is a device that is able to start a steppermotor when turned and stop the motor when stopped turning it, via a driver like my M542T as far as I know but maby I am wrong) is a line driver version having 6 terminals as the Tosoku version, and not a version with only 4 terminals, can I then use it with the 0V connected to the drivers PUL- and DIR- and A to PUL+ and B to DIR+.
Will MPG A to driver PUL+, MPG A (with line over) to driver PUL-, on MPG B to driver DIR+, and on MPG B (with a line over) to driver DIR- not work, is that not what they say in the manual for the M542T, there is diagrams for connections to driver with common anode and common catode in the manual but no diagram for line driver,
and then maby have 2 pulse generators, I have seen some that goes from 1hz-10khz with manualy operated start/stop and direction that gives me the x100 and x1000,
theese connected along with my MPG and selected via a switch with 3 settings, step 1 for operating with my MPG, and step 2 for the slow continous speed and step 3 for the high continous speed, so I dont have to learn how to program Arduino.
I uploaded pictures of my items and screenshots of manuals, can you see them ? I cant see them now I think of it. they where visible in the preview.
Kind regards
Steppernewbie

Neale
14-02-2018, 07:16 AM
Hi m_c
Thank you for your answer.
If my MPG (Answer to magicniner : A Manual Pulse Generator is a device that is able to start a steppermotor when turned and stop the motor when stopped turning it, via a driver like my M542T as far as I know but maby I am wrong) is a line driver version having 6 terminals as the Tosoku version, and not a version with only 4 terminals, can I then use it with the 0V connected to the drivers PUL- and DIR- and A to PUL+ and B to DIR+.
Will MPG A to driver PUL+, MPG A (with line over) to driver PUL-, on MPG B to driver DIR+, and on MPG B (with a line over) to driver DIR- not work, is that not what they say in the manual for the M542T, there is diagrams for connections to driver with common anode and common catode in the manual but no diagram for line driver,
and then maby have 2 pulse generators, I have seen some that goes from 1hz-10khz with manualy operated start/stop and direction that gives me the x100 and x1000,
theese connected along with my MPG and selected via a switch with 3 settings, step 1 for operating with my MPG, and step 2 for the slow continous speed and step 3 for the high continous speed, so I dont have to learn how to program Arduino.
I uploaded pictures of my items and screenshots of manuals, can you see them ? I cant see them now I think of it. they where visible in the preview.
Kind regards
Steppernewbie
You have a few issues here, and unfortunately we do not have enough information to answer all your questions. I'll start with a few basics, in case you do not know these things already.

The stepper driver has three inputs (two terminals per input). These are step, direction and enable. Ignore "enable" - if you do not connect anything to this, the driver defaults to enabled anyway. The "direction" input does not need pulses. Put 5V across it and the motor will turn in one direction; remove the 5V input and the motor will turn in the other direction. The motor will only turn when pulses are applied to the "step" (or "pul") input. The motor will move one step per pulse, and its direction depends on the "dir" input as described. A standard stepper motor will have 200 steps per revolution so each pulse moves the motor spindle by 1.8 degrees.

You need an MPG that provides a "pulse" output, that is, one pulse per click of the wheel. I'm not sure what the Tosoku MPG output is, but I have seen one reference to "A,B quadrature" output. That suggests to me that the MPG gives a series of pulses on two outputs which are 90deg out of phase. This means that whatever is using the pulses can not only see a pulse train (one step per pulse) but can also work out the direction. Unfortunately, the stepper driver cannot use these signals directly. What you can do, I think, is just connect the A output from the MPG to the Step input on the driver, connect 5V via a switch to the Direction input, and see if that works. The stepper motor will turn in the direction set by the Dir input and will move one step per click of the wheel, but it will not make any difference which way you turn the wheel. Without more information on the MPG outputs, I cannot really say much more than this.

That's the basics. If you can get this working, you will have more-or-less what you wanted. The MPG appears to have a "x1/x10x100" switch, which I guess configures it to deliver one/ten/hundred pulses per click of the wheel, which is also what you want. You can also use the DIP switches on the driver to tell it to use "microsteps" - that is, instead of the 200 steps per rev of a standard motor, these use some clever electronic techniques to simulate more steps per rev. Typically, people use stepper motors with x8 microstepping giving the equivalent of 1600 steps/rev.

With a bit of work, I'm sure that you could put some simple logic circuitry together to take the A and B quadrature outputs from the MPG and turn them into step/dir signals for the stepper, but that's a bit too complicated for me at this time of the morning!

Doddy
14-02-2018, 07:31 AM
With a bit of work, I'm sure that you could put some simple logic circuitry together to take the A and B quadrature outputs from the MPG and turn them into step/dir signals for the stepper, but that's a bit too complicated for me at this time of the morning!

The quadrature outputs *should* suit a direct coupling with the stepper driver, connect either A/B to Step, and the other to Dir - you use one of the two quad outputs as a clock and, depending on direction of travel, the alternate phase will either be 0 or 1 (and so provide the direction control).

OP suck it and see - just check the outputs from the MPG - sling a meter on and confirm that for each detent moved, each output changes from 0 to 5 volts (the first one that I had used an open collector drive - and so has to be used with the negative-side switching). All signal levels from the MPG will be low current, low voltage, and the input to the stepper driver will be via a current-limited opt-isolator designed to run off 5v signalling. There's not a lot to go wrong if you know one end of a bit of wire from the next.

All this will give you is an ability to rotate a stepper in response to the rotation of the MPG wheel. That's going to get awfully boring to use on a mill.

steppernewbie
14-02-2018, 07:46 AM
Hi Neale
Thank you for your answer and explanation, just to clarify my MPG is a Chinese one with no manual so the reference to Tosoku is only because for that one I could find diagrams of pulse output for a model with 6 terminals, so I guess there is only left to try it and see what happens.
From what I can see in the driver manual the driver can use both the PUL and DIR signals directly, the DIR signal just has to come 1.5Ms before the PUL signal.
Can you tell me if you can see the pictures that I uploaded ?, because I cant see them.
Kind regards
Steppernewbie

Clive S
14-02-2018, 09:10 AM
Can you tell me if you can see the pictures that I uploaded ?, because I cant see them
I don't see them

Neale
14-02-2018, 09:50 AM
The quadrature outputs *should* suit a direct coupling with the stepper driver, connect either A/B to Step, and the other to Dir - you use one of the two quad outputs as a clock and, depending on direction of travel, the alternate phase will either be 0 or 1 (and so provide the direction control).

Good point - I hadn't visualised the pulse timings in my mind, but even though the pulse train for the Direction signal will be changing, it will always be in the correct state when a Step pulse happens to give correct direction. As long as the Dir-Step pulse edge interval meets the stepper driver minimum timings, anyway. It's actually easier than I thought!


All this will give you is an ability to rotate a stepper in response to the rotation of the MPG wheel. That's going to get awfully boring to use on a mill.
Actually, I think that this is exactly what the OP wants. He finds it difficult to wind the Z handle, and wants to motorise it. With a DRO already in place, this doesn't sound like a silly thing to do. Mind you, it might well lead on to a desire for full CNC control!

steppernewbie
14-02-2018, 10:31 AM
Hi Neale and Clive S
Thank you for reply. To Neale : That is exactly what I want, motorizing the Zaxis
I have tried to upload pictures again, and now I see them, can you ?
Kind regards
Steppernewbie

Neale
14-02-2018, 10:40 AM
Yes, I can see them now. Connect A/~A to the step inputs, B/~B to the direction inputs, and you should be fine. It does not matter which A/~A goes to step + or -. If the motor turns the wrong way, change the B/~B wires on the Dir input (i.e. swap wires going to + and -).

steppernewbie
14-02-2018, 10:43 AM
Hi Neale
I will try to wire it all up later today.
Kind regards
Steppernewbie

JAZZCNC
14-02-2018, 11:30 AM
This will work as described directly from MPG but the problem will be the number of pulses per turn, probably 100, will mean take forever to move any distance.
For instance, even at full step it will take 2 turns for 1 rev of motor. I'm pretty sure those drives smallest micro stepping is 400 so that will be 4 turns per rev.
To move quickly you'll need multiplier and this will need some hardware.

Could use something like this if just want to drive up/down.
https://www.ebay.co.uk/itm/Stepper-Motor-Driver-Controller-PWM-Pulse-Signal-Generator-Speed-Regulator-Board/272654020131?epid=858674962&hash=item3f7b722e23:g:sg8AAOSwrhBZCAYH
or this
https://www.ebay.co.uk/itm/Speed-Stepper-Motor-Driver-Controller-with-Remote-Control-4-lead-wire-UK-B163/122915535006?epid=782774623&hash=item1c9e56389e:g:W5YAAOSw5ZBWNHpQ

You'd have probably been better of buying analog drive that allows you to connect potentiometer and drive with voltage.
https://www.zappautomation.co.uk/uim243l02bt-miniature-stepper-motor-driver.html

steppernewbie
14-02-2018, 09:57 PM
Hi Jazzcnc
The slow speed (only with MPG) is exactly what I want , so I can dial it in within less than 1/100mm.
The first item is the one I was thinking about, and I have maby also another plan with theese so they can be controlled by MPG, getting back to that later.
My health did not allow me to wire up the setup today, getting back with results when done.
Kind regards
Steppernewbie