Nema 23 question

Nema 23 motors come in various torque sizes. The 140 oz Nema 23’s work fine with the standard controller, but if you want the more powerful 262 oz Nema 23 motors you would be better of with the X-Controller.

Ahhh I need to get the xcarve controller then

Not really sure if that would solve your Z axis problem. The Z axis draws less power than any of the other motors and does not need to be as powerful as the X or Y motors. So if you are losing steps on Z then you probably need to adjust the voltage level to the Z or fix a mechanical problem that is causing the Z axis to bind. Or it could be as simple as a loose pulley.

@AngusMcleod Here is everything you wanted to know about stepper motors with pictures, diagrams, explanations, examples and lots of words with more than one syllable. :smile:
https://www.geckodrive.com/gecko/images/cms_files/Step%20Motor%20Basics%20Guide.pdf

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Simple rule of thumb is that maximum voltage for the stepper is:
32 * sqrt (inductance).
Maximum current capacity for the power supply needs only to be 2/3 of the sum of the current for all motors.
My 142 in/oz motors have an inductance of 2.2 mh (millihenries) which gives a maximum voltage of 47.6V. The motors are rates at 2.8A so 2/3*(2.8*4) which is 7.46A.
I have a 48V, 10A supply which is much more than needed. As simple unregulated supply is all that is needed but the enclosed, 48V 8.33A supplies such as sold by Inventables, is what I use.
Controller is a Gecko G540 which has a rated voltage maximum of 50V and 3.5A per driver.

anyone has experience with a gecko driver?

@anon68752607 I use a Gecko G540, what do you want to know?

anything :slight_smile:

i hear it is very good. But what does it run? Mach 3? Does it come with everything you need, like the connectors and power supply?

I’m sorry I am still learning every day and stepper motors are kind of new to me.

Im running also G540 its totaly different. Much better en smoother.
Ok for importing in the EU we have to pay extra taxes but worth every extra €.

mach 3 has a learning curve like every new program but after all great. I m happy with the whole setup.

You can order with the connectors or without and with or without the resitors. depend on what motors you are running if you need some or not.

Grtz Koen

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It will depend where you buy it from as to what comes with the G540. I bought mine direct from Gecko and just got the bare controller but I have seen suppliers selling it in a kit with power supply, case etc.
It’s very easy to use and requires no setup or tuning. You just connect a suitable value resistor across two pins of the connector to set motor current i…e no pots to adjust. Actually there is an adjustment but that is for mid band resonance and adjustment is really optional.

It does expect a parallel port connection to the computer but these are easy to source if your computer does not have one. I’m running the G540 under Linuxcnc (free!) but plan to give it a try with Easel ‘soon’. Connecting the necessary control signals from an Arduino is not difficult.
I’ve just finished rebuilding the controller box ( Milling panel for new controller ). All it has in it is the G540, a power supply (48V, 8A) and a few connectors.

I’ve been running NEMA 23s on all three axes for more than a year using the stock grblshield that came with my SO2 kit. I added a small 2" fan blowing on the card to keep it cool. No problem so far and I’ve had runs of 3-4 hours routinely.

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Koen, waar heb jij de uwe gekocht?

I have a Gecko on each machine and ordered DB9 connectors that had a pot instead of a current limiting resistor. That makes them infinitely more adjustable than trying to find a specific resistor. Most Gecko’s come with the DB9 connectors.

And yes, incredibly smooth and fast at 48 volts. You should check the newer models because the models I have come with a 10 amp cap on powerdraw. It shuts down to protect itself - so no harm done. That’s where the pots come in handy.

Here is where I got mine (courtesy of someone on this forum): http://www.soigeneris.com/ez_g540___set_of_4-details.aspx

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i have those same DE9 connectors with the adjustment pot. The two CNC routers I have use different spec motors so I can move the controller between machines without adjusting anything.

I hope to do some testing on my grbl to G540 adapter today. Running the X-Carve via grbl with a Gecko G540 controller

Ok I have got it all set up on my desk. I got the motors to turn, but the steps per mm settings are all wrong obviously.

So here’s my questions for the mach3/geckodrive experts:
do i use microstepping? If so which axis and how do i set that up?

What are ballpark motor tuning settings. The steps per mm I can figure out depending on my drive system, but I have no clue about where to start with velocity and accelleration settings

23 nema motors are larger holes for screws are different for xcarve 1000. Do I have to drill new holes on plate?

I have the stock 500mm with the NEMA 23s installed. The 1000mm should have the same hole pattern.

For powering my NEMA17 motors I use the Pololu 8825 drivers. I did a speed test at 8000 mm/min and that works fine. In real life I only cut light materials and this power train proved to be sufficient for me. The steppers are set to 2.2A and the motors are rated at 2.5A In a long job (1 hr for me) the X gets warmer than the Y and Z but not to dangerous levels.

The documentation on the Pololu.com website about stepper motors and drivers is very easy to understand. I recommend you take a look.

The Inventables NEMA 17s are rated at 1.68 amps per phase. Hopefully, you have someone else’s NEMA 17s.

Yes, I am using the Wantai Motors NEMA17 with a holdong torque of 4.8 Kg/cm = 47.1 N-cm They are rated for 2.5A

It proved to be cheaper on shipping an import taxes to buy these locally,

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