STEPPERCHINA

Whilst looking a parts for a Kossel, a large Kossel (see Kossel 3D Printer), I came across these aluminium vertices for 2040 aluminium from RobotDigg, see 2040 or 3030 Alu Vertex for Kossel XXL or XXXL. On that product page they recommend using Nema 23, en lieu of Nema 17, stepper motors and, indeed, offer a vertex machined especially to take a Nema 23 stepper motor.

Now, Nema 17 stepper motors are pretty well covered in the RepRap forums, and there are three common favourites. However, the choice is not so clear for Nema 23 stepper motors. I decided to do some research on which Nema 23 stepper motors would be appropriate.

Links

Take a look at the RepRap Wiki page for Nema motors.

From Choosing stepper for a delta:

Using NEMA23 stepper motors for printers

For large machines, there are questions of the interest to use larger size steppers for movement or extruder, say Nema23 sized motors. However, Nema23 steppers are less optimised than Nema17 for micro-steps so there will be loss of precision. In addition, the rotating inertia is larger, so rapid change capacities may be reduced, driving to difficulties at corners. All steppers will have an increase of vibrations at medium step rates. This is called ‘mid-band resonance’. NEMA 23 steppers may be more prone to have this problem, at a lower frequency than NEMA 17 stepper motors. So, it is preferable to use long NEMA 17 stepper motors than NEMA23. Electrically, larger motors will need more current, whatever their size.

Nema 17 is most likely more than adequate, depending on your speeds. The bigger challenge is going to be a bowden system that isn’t 6 ft long…  Perhaps a counter-weighted bowden floating head.

From Running NEMA 23 motors, again after RobotDigg’s recommendation:

…have been advised (by RobotDigg who make the frame corners) to consider NEMA 23 (76mm). These are rated at 6.7V 2.8A

2.8A is too high for the Duet. However, you can also get Nema 23 motors with 1.5A or 2A rated current, which would be a better match. You will need 24V or 30V power.

A larger machine doesn’t necessarily need larger motors, because the effector of a large printer need weigh no more than the effector of a smaller printer. The belts will weigh more, but you can easily work out the additional torque you need to achieve the desired acceleration, given the additional mass of longer belts.

From NEMA23 steppers seem weak:

I’m using TeaCup firmware with RAMPS 1.4 electronics. It’s a custom design of 3D printer, with a larger print area. It’s essentially a Prusa Mendel iteration 2 in a wooden box frame instead of the triangular frame. The Z and X axis are powered by NEMA23 steppers with TB6560 stepper drivers instead of the NEMA17. Unfortunatly the NEMA23’s seems to be weaker then the NEMA17 and I’m not sure why.

The original RAMPS1.4 elektronics design has two steppers fed by the same stepper drive for the Z as. I changed this to two TB6560 stepper drivers receiving the same CLK, DIR en EN signals so that each NEMA23 has his own dedicated TB6560. The NEMA23’s have their own seperate power supply, an AC to DC convertor with an output of 24V and 10A, this feeds a total of three TB6560’s with one stepper motor each.

I’ve tried 3A and 2.2A, dont know if they get warm. I’ll test it.

The rest of the TB6560 settings is at stop current 50%, excitation mode 16, and decay setting 100%.

The maximum current you should use on those motors in bipolar series mode is 2.1A. At that current they will get hot. I suggest you use 1.6A or 1.9A. The static voltage drop at 2.1A would be 3.15V, so your 24V supply should be entirely adequate. Are you certain you have them wired correctly, i.e. yellow linked to blue and orange linked to brown? What load are they driving?

From Duet3D – Choosing stepper motors

Nema 23 motors offer higher torque than Nema 17 motors. The Duet WiFi and Duet Ethernet can drive them if you choose them carefully, in particular in respect of rated current. Look for a rated current of around 2.8A. You should use 24V power.

• Size: Nema 17 is the most popular size used in 3D printers. Nema 14 is an alternative in a highly-geared extruder. Use Nema 23 motors if you cannot get sufficient torque from long Nema 17 motors.

From RobotDigg – Reprap Stepper Motor:

Just as the reprap forum has been showed up, Nema14 and Nema17 Stepper are popular as Reprap Stepper Motor in small and medium sizes of 3d printers like Huxley, MendelMax. Nema23 is supplementary to Nema14 and Nema17 Stepper Motors.
We have some comments on the Nema23 stepper motor. Robotdigg do Not Nema23 Stepper is the best choice for Darwin or other reprap strong 3d printers if you use a 2A stepper driver like A4988 driver. At least 24V power supply for a Nema23 stepper and a strong stepper driver up to 3A or 4A are ideal. So if you use 12V and a stepper driver within 2A drive ability, a Nema17 long body stepper motor is recommend or a geared stepper motor is good. A Nema17 60mm stepper motor can have 0.65N.m holding torque. In the other side, a Nema17 60mm stepper motor is much cheaper than a Nema23 stepper or a geared nema17 stepper motor.

For small quantity less than 20pcs, short body Nema17 Stepper Motor 34mm and 40mm long, RobotDigg recommend you source them in your local area. Or buy from our dealers, now we have dealer of 17HS3001-20B Nema17 40mm Stepper in Australia, Brazil, Spain and U.S. 12USD, 14USD is reasonable price from dealers we think, shipping cost, VAT and a piece of profit margin. We will list our dealers out as soon as possible here.

Recently we have some reports on Wiring Questions on our Reprap Stepper Motors. And we have a look on it and find that it is not individual. The questions is that on motor side the color of the lead wires are Red(A+), Yellow(B+), Grey(A-) and Green(B-) in turn. As usual, on the other side the stepper driver B-, B+, A+ and A- but the Mark on A4988 Driver can make you confused. See the following: From the lower 1B, 1A, 2A and 2B. The question is that 1B and 1A is one phase(one coil) and 2A and 2B is the other phase(one coil).

http://www.pololu.com/catalog/product/1182
A4988 Driver
To solve the wiring question using our stepper motor, you need to exchange the Yellow(the 2nd) and Grey(the 3rd) on the motor side or the other side of the lead wire(Plug to Stepper Driver).

RobotDigg welcome your order of our NEMA17 60mm 0.65N.m Stepper Motor and Threaded Rod Nema17 Stepper Motor with strong Tr8*8 Leadscrew.

Back to Nema23, is using a bigger size stepper motor means more powerful your 3d printer will be?
The answer is absolutely NOT.
RobotDigg find that most of 3d printer makers are trying to buy a longer body stepper motor. But that’s only one side of the solution of higher torque output. The other side is the Stepper Driver. A4988 stepper driver is very popular in 3d printing industry, it’s a good driver which can drive up to 2A. But when you use it to drive a long body stepper motor Nema17 48mm or 60mm Stepper when you give it 12V power supply, you find that you still have the question of low torque output. How to figure it out? Increase the power supply. You may say you have a 12V power system, so increase the set Current, at least equal to the Rated Current of the stepper motor you have in your 3d printer system.
OK, we are a little far. Why a Nema23 Stepper is not that ideal for your 3d printer?
As we know, Nema23 is very popular in CNC machines. We also can see that a CNC machine usually has 24V power supply.
Set the current of the stepper driver the Rated Current of the stepper motor. A stepper motor with rated current 1.5A, if you give only 1A, the holding torque could be half or even lower, especially when increase the speed and heat generation after a long time run.
Is there a Nema23 stepper motor good for 3d printer and can be drived by A4988 stepper driver?
The answer is yes. RobotDigg are glad to show you a Nema23 stepper of this kind in the near future.
Instead of a Nema23, are there a Nema17 Stepper Motor can meet my need?
A Nema17 60mm with Rated Current 1.5A(within 2A, set your A4988 stepper driver at 1.2A or 1.5A won’t hurt the stepper driver. But if you set the stepper driver at 2A, it cann’t run long time, the stepper motor may pause.), a Holding Torque 65N.cm 92oz.in which is really with enough power for your 3d printers.

Now we know the stepper motors required for our project we can match them to a suitable CNC controller. The controller converts the g-code we’ve created and sends step pulses to the stepper motors. It also takes input signals from the machine such as limit switches and E-stops.

So there are 3 things we need to know:

Number of Axes. So usually 3 for routers and 4 for a foam cutter
Current and voltage we need to supply to the stepper motors
How do we intend to connect the computer to the CNC controller
Number of Axes
CNC routers can use 3 or 4 axis controllers. There is only 3 planes of movement X, Y and Z but some designs use two stepper motors on one axis. My OX CNC router uses two NEMA 23 on the Y-Axis as its a gantry type router. Some move the table bed for the Y-Axis on sliders and only need 1 motor for the Y-Axis. Like a 3d printer bed.

Y-Axis complete and running very smooth
Foam cutters need 4 axes to allow the hot wire to move in any direction on 4 planes usually X,Y,U and V.

Generally, you are going to need at last NEMA23 from 175oz/in upwards unless your machine is very small such as a CNC engraver. These are quite often used for making Printed Circuit Boards(PCB) and if you check the description they will say only for soft materials.

So let’s look at a couple of examples.

For routers, the cutting material plays a big part in our decision. Harder materials will need a more powerful stepper because the cutting bit is being driven into the material.

The WorkBee from Ooznest in the UK which is based on the OpenBuilds design. It uses NEMA23 of 175 oz/in. If you check some of the offerings on eBay for 6040 CNC routers you’ll quite often see in the description 57 size motors, which is the metric equivalent of 2.3 inches or NEMA23’s and these usually come with 175-200oz-in motors

If you intended to cut very hard materials then high torque steppers motors will be required usually around 300-400 oz/in and you may need to go up to NEMA34 and you will need a strong frame to support that.

https://forum.arduino.cc/index.php?topic=572700.0

Step motors are widely used in automation due to their high resolution, precision positioning, minimal control electronics, and low cost. As an open loop system, traditional step motors are driven without the need for sensors to feed information back to a controller; however, the open loop configuration of step motors has challenges.

Position Verification — When pushed beyond its limits, a step motor will stall before reaching the endpoint. This event typically occurs when motors are not adequately specified for high-cycle applications. An encoder can provide position feedback at the end of the motion profile, indicating if the step motor stopped before reaching the end position. The controller compares the encoder counts that define the actual motor position to the target motor position at the end of a move to determine if there is a difference. If the encoder counts don’t match to the actual motor position, a corrective move or motion profile is calculated and executed.

Stall Detection — Stall detection notifies the user/system/machine as soon as a motor stall occurs, eliminating the uncertainty of whether or not the motor reached its target position. A more advanced function than position verification, stall detection (Figure 2) enables the controller to compare the registers of the encoder counts and target motor position on a continuous basis instead of just at the end of the move.

Stall Prevention— While greatly increasing system functionality, stall detection does not inherently improve step motor performance; it still requires the operator to perform a corrective move and re-reference the axis to the home position. Stall prevention, on the other hand, dynamically and automatically adjusts the move profile to prevent a stall, enabling the motor to operate with constant torque to get into an accurate end position without stalling.

Servo Control and Increased Motor Torque — Using stepper motor encoder feedback to servo-control, a step motor increases motor torque for greater dynamic performance. With peak torques up to 50% higher than the rated holding torque of the motor, the servo-controlled step motor system can operate at higher acceleration rates and with higher throughput for faster machine cycles.

When using a stepper motor, integrating an incremental encoder is relatively straightforward. Still, there are some general guidelines to consider.

Incremental encoders (like any stepper motor encoder) all function as part of a feedback system — providing closed-loop operation. Using information from the encoder, the drive system alters motor operation.

However, incremental encoders don’t keep track of position once power is lost. They also need a reference position to return to every time upon startup.

Keep this in mind when using and driving a stepper motor, because the machine design must set to a reference position when using incremental encoders.

Incremental encoders are often useful when speed control requirements are part of a system. If there’s less concern over the position of the shaft — and more of a concern over how fast it is moving — then the fact that incremental encoders don’t track position once off is less critical. In fact, here their simple operation and low price benefit the design.

Incremental encoders keep track of speed where only the difference between two positions is necessary.

There are a few different methods to mount an encoder to a stepper motor. Each of them is useful for various situations, and the choice depends on the motion system.

Incremental encoders with shaft mounting …
A coupling connects the encoder to the shaft. This creates mechanical and electrical isolation, but also adds cost because the coupling is an extra part and because this method requires a longer motor shaft.

Incremental encoders with a hub or hollow-shaft setup …
The encoder directly mounts to the motor using a spring-loaded tether. This is a design that is easy to install and requires no alignment. The only caveat is that this geometry requires careful electrical isolation.

Incremental encoders with a bearingless or ring mount …
Here, the sensor is in the form of a ring that mounts to the motor’s surface. A wheel mounts to the motor’s shaft. There are useful for heavy-duty applications.

What are the advantages and disadvantages of the different functionalities?

Nema 17 motor is not standard for electrical characteristics of the stepper motor. It is just faceplate and mounting holes standard to make it easier to interchange motors. Most likely you have to check from the specification that what is rated current for that motor and is it unipolar or bipolar one. Choose driver based on that.

Note: Drive can always be more powerful than the motor, but you have to limit your current from the drive side. It’s also possible to use chopper drives with the less current rating, but then your motor runs underpowered.

But one can definitely make assumptions on the motor size that NEMA 17 could use 1A – 2A current and NEMA 23 motor could use around 2A – 5A current.

Final words
This articles scope was to make a high-level overview of how to drive a stepper motor. I hope I delivered and you have now a better understanding of this topic and can start experimenting.

Now the real fun and learning begins.

There is a lot more than these basic concepts I introduced. There will be problems with vibration, torque, cooling motors, choosing hardware, missing steps, calculating steps and configuring software. Stepper motor projects are prone to problems because of all dependencies in the chain. Starting from hardware or power to bad configuration or just wrong program. Basic debugging skills are very handy here and it helps to have extra components to switch in case of hardware malfunction.

Did I answer all basic questions? Or I missed some crucial concept that left you wondering? Let me know about it in the comments. I would be grateful to know so I can improve this article.

The working principle of the Linear Stepper Motor

Circuit diagram to control Nema17 stepper motor with Arduino is given in the above image. As A4988 module has a built-in translator that means we only need to connect the Step and Direction pins to Arduino. Step pin is used for controlling the steps while the direction pin is used to control the direction. Stepper motor is powered using a 12V power source, and the A4988 module is powered via Arduino. Potentiometer is used to control the direction of the motor.

If you turn the potentiometer clockwise, then stepper will rotate clockwise, and if you turn potentiometer anticlockwise, then it will rotate anticlockwise. A 47 µf capacitor is used to protect the board from voltage spikes. MS1, MS2, and MS3 pins left disconnected, that means the driver will operate in full-step mode.

Complete connections for Arduino Nema 17 A4988 given in below table.

S.NO.	A4988 Pin	Connection
1	VMOT	+ve Of Battery
2	GND	-ve of Battery
3	VDD	5V of Arduino
4	GND	GND of Arduino
5	STP	Pin 3 of Arduino
6	DIR	Pin 2 of Arduino
7	1A, 1B, 2A, 2B	Stepper Motor

NEMA 17 is a hybrid stepping motor with a 1.8° step angle (200 steps/revolution). Each phase draws 1.2 A at 4 V, allowing for a holding torque of 3.2 kg-cm. NEMA 17 Stepper motor is generally used in Printers, CNC machines and Laser Cutters.

NEMA17 Stepper Motor is commonly used in CNC machines, Hard Drives and Linear Actuators. The motor have 6 lead wires and rated voltage is 12 volt. It can be operated at lower voltage but torque will drop. These motors has a step angle of 1.8 deg., this means that it has 200 steps per revolution for every step it will cover a 1.8° hence the level of control is also high. These motors run on 12V and hence can provide high torque. So if you are looking for a compact easy to use stepper motor with high torque then this motor is the right choice for you.

Operation of Nema17 is similar to normal Stepper Motors. NEMA 17 stepper motor has a 1.7 x 1.7-inch faceplate, and it usually has more torque than the smaller variants, such as NEMA 14. This motor has six lead wires, and the rated voltage is 12 volt. It can be operated at a lower voltage, but torque will drop. Stepper motors do not rotate they step, and NEMA17 motor has a step angle of 1.8 deg. means it covers 1.8 degrees in every step. Wiring diagram for NEMA17 is given below.

Stepper Motor Applications
CNC machines
Precise control machines
3D printer/prototyping machines (e.g. RepRap)
Laser cutters
Pick and place machines

NEMA17 Dimensions

NEMA 23 is a high torque hybrid bipolar stepper motor with a 2.3×2.3 inch faceplate. This motor has a step angle of 1.8 deg., this means that it has 200 steps per revolution and for every step it will cover 1.8°. The motor has four colour coded wires (Black, Green, Red & Blue) terminated with bare leads. Black and Green wire is connected with one coil; Red and Blue is connected with other. This motor can be controlled by two H-bridges but it is recommended to use a stepper motor driver.

 
How to use NEMA 23 Stepper Motor
As mentioned above this stepper motor draws high current so instead of controlling it directly using H-bridges, use an appropriately powerful stepper motor driver. To know how to make this motor rotate we should look into the coil diagram below.

As you can see from above diagram this motor has four wires in different colours. This motor can be made to rotate only if the coils are energized in a logical sequence. This logical sequence can be programmed using a microcontroller or by designing a digital circuit.

 

Stepper Motor Applications
CNC machines
Precise control machines
3D printer/prototyping machines (e.g. RepRap)
Laser cutters
Pick and place machines

NEMA 23 Stepper Motor Dimensions

The automation aspect of certain types of systems and equipment will depend on the type of stepper motor that you use. NEMA hybrid stepper motors are recommended if you want a versatile stepper motor that can work with most industrial automation requirements. The technology behind NEMA stepper motors, like the NEMA 23 stepper motors, is far advanced because of its precision and high-torque design.

Speed and torque are the two most crucial factors when choosing the right stepper motor for automation. NEMA hybrid stepper motors are preferred in industrial automation because they provide more power than the lower end models. NEMA 23, in particular, is a recommended hybrid stepper motor due to its powerful torque and speed, both of which are essential factors that can improve the performance and reliability of automated equipment and systems.

A NEMA hybrid stepper motor can be useful in making semiconductors. It can be complicated to manufacture semiconductors due to the high amount of output that is involved in the processes. Hence, it is important for the automation system to be reliable for robotics control, measurement, inspection, and quality assurance.