Monthly Archives: May 2015

Spring Time special: A Stepper motor with superior EMC performance

AllDrives & Control Press release

Staffordshire, May 14, 2015 – Alldrives & Controls, who represent Nanotec Germany in the UK and Ireland, has a spring in it step with the new SC3518 series from Nanotec.



EMC problems, like the dark days of winter, are now in the past, as Nanotec launches stepper motors which not only feature a very high torque, but also have excellent EMC properties.

The SC3518 series are 2-phase hybrid stepper motors with frame size NEMA 14 (35 mm) and a 1.8° step angle, and depending on the motor length, the holding torque is between 0.18 and 0.32 Nm.

Like all motors of the SC series (NEMA 8, 17 and 24 sizes) from Nanotec, the new SC3518 stepper motor is connected via an integral connector enabling easy cable loom integration, saving costs, in customer applications.

Together; with the shielded cable, which is standard equipment, the two outer pins of the connector are attached to the motor housing, creating a shield to housing connection with excellent EMC performance. Radiated EMC Interference from the motor lines, which can cause problems in existing sensors, is effectively suppressed.

The SC3518 motors are available with an integrated optical encoder NOE1 with up to 2000 increments/rotation for closed-loop control.

Or as a standard Stepper motor for open loop control, which can be converted to a sensor-less closed loop control using the innovative “C5” Drive controllers, also from Nanotec.

On account of their high torque yet small size, motors of the SC3518 series are ideal for use in laboratory automation or service robotics.

About Nanotec

Nanotec is a leading manufacturer of motors and controllers for high-quality drive solutions. The company has been developing and marketing a broad range of products since 1991. Nanotec technology is primarily used in automation systems, laboratory automation, medical devices, the packaging industry, and semiconductor production. Nanotec has its company headquarters in Feldkirchen near Munich with subsidiaries in ChangZhou, China, and Medford/MA, USA.

About Alldrives & Controls

Alldrives & Controls is a leading specialised technical full service distributor of motors and controllers for high-quality drive and automation solutions. The company has been sourcing and marketing a broad range of products since 2009. Alldrives & Controls technology is primarily used in automation systems, laboratory automation, medical devices, packaging industry, and semiconductor production. Alldrives & Controls has its company headquarters in Tamworth, Staffordshire UK .


Stepper Motor Sensorless Control; What You Need to Know

So you’re in need of a motor for precise positioning. What would be your preference?

Stepper motor or servomotor?

Many smart engineers like yourself will agree, that the answer lies resolutely in the application requirements.

For example, the compact stepper motor with its ability to run open-loop may be all that’s required for simple tasks, and certainly it makes a very affordable option.

However with high performance dynamic operations, the issues a stepper motor holds around resonance, excessive heat and step-loss often see it take a back seat to the pricier servomotors that utilise advanced control methods.

But things are starting to change.

The introduction of stepper motor sensorless control is already raising eyebrows in the OEM industry.

As it turns out, Nanotec® have found a way to replace expensive stepper motor encoders for virtual encoders within the controller. This means that our faithful friend the stepper motor, can now be operated just like a servomotor but without the high price tag.

Suddenly the query of stepper vs. servo gets interesting; but what does sensorless technology mean for us?

Less heat, no resonance, longer service

With stepper motors receiving a constant stream of full current, it’s no surprise that the resulting increase in high temperatures and vibrations decrease service life and eventually, effectiveness.

However now that the stepper motor can be controlled via the virtual encoder, they are able to receive the required current to perform actions, just like a servomotor. This ensures the stepper motor remains considerably cooler with almost no resonances.

This improved performance protects the motor and its bearings, increasing service life and naturally supplying the added benefit of energy efficiency. Better for the environment and for your bank balance.


Step-loss? What step-loss?

Another argument to avoid stepper motors is the issue of step-loss; missed actions caused by resonances and instability which of course go undetected with open-loop systems.

Nanotec® rectifies this with the closed-loop system that delivers a controlled current to the motor, so that resonances are removed and missed steps (up to its maximum torque) are a thing of the past.

The benefits of the closed-loop system now mean that the controller can recognise inconsistencies in the motor, adjustments can be made and alerts sounded.

And the mechanical issues?

Usually these can be minimised using precise mathematical models and calculating parameters, which let’s be honest, isn’t a quick and simple solution.

Thankfully the Nanotec® sensorless system operates with few parameters and even these can be set using an auto-setup routine that automatically determines all the required parameters. Now we’re talking.

All this additional motor control not only avoids instabilities and step-loss, but Nanotec® noticed that at high speeds, the sensorless control actually worked better than an encoder, even removing speed fluctuations of the motor at low resolutions.

As you can see, the argument for use of sensorless technology grows ever more compelling; yet it seems that’s not all.

Sensorless technology can benefit almost all stepper motor applications with its ability to be combined with open-loop control.  When necessary and at low speeds, the system is able to switch to open-loop mode; which still continues to work effectively considering resonance isn’t an issue where only a few steps are needed.

So it seems whether your application deals with speed, or positioning, this combined approach could work for you.

In the end, regardless of your motor preference, there is no denying that the main objective is for your system to run as smoothly and efficiently as possible. We believe Nanotec® have worked hard to provide this for their customers, with a responsive stepper motor that not only uses impressive sensorless technology, but doesn’t break the bank either.

Perhaps this calls for a change of opinion for future precise positioning motors? What are your thoughts?

For more details on a wide range of motors visit our products page or contact us for helpful advice.

Source: Nanotec® (2015)

Nanotec Application Notes