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Sometimes one has to (still) use a dedicated net just for servos but that is old. Different fieldbuses and/or servo drive interfaces may support a partial frame; for example, one may only be able to set a control word which might be position or torque command while some may support a full parameter frame or command set which exposes a plethora of servo parameters and variations between the two extremes. Speed is also a consideration i.e. may only be fast enough to do motion control or fast enough to close a servo torque loops and/or fast enough to incorporate feedback devices e.g. force or range sensors (without wiring directly to the servo drive).

Stepper motors are now widely used in the industrial areas, but from time to time some problems with stepper motors occurs as follows. Aimed to these problems, there are some troubleshooting for your reference.

1. How to control the direction of stepper motor?
2. When stepper motor generates vibration and noise, how to do it?
3. Why the stepper motor doesn’t rotate or move back and forth after it is powered?
4. Why the torque of stepper motor is decreasing with the rise in rotational velocity?
5. Why stepper motor can run normally at low velocity, but can’t start at certain higher velocity with some noise of whistler?
6. How to prevent the power interference of stepper motor?

Stepper motor is an open-loop control motor which transforms electric pulse signal into angular displacement or linear displacement.  However, there are some errors occuring between the actual angle stepper motor rotates and the theoretical step distance. There are some certain errors from one step to any other step, but the step number of each cycle of the stepper motor is the same. In the case of no step loss, the step error is not accumulated for a long time.
How to prevent step loss with stepper motor as the above mentioned? First of all, we need to know why stepper motor losses step?

1. The rotor acceleration is slower than the rotating magnetic field of the stepper motor.
2. The average speed of the rotor is higher than the average rotating speed of the stator magnetic field.
3. The load inertia of stepper motor is large.
4. The stepper motor produces the resonance.

The servo drive is a kind of controller to control the servo system. Its function is similar to the frequency effect on ordinary AC motor, which belongs to a part of the servo system and is mainly applied in high-accuracy positioning system. Generally, the servo motor is controlled by three ways, location, speed and torque, so as to realize high precision positioning of transmission system.

Stepper motor is an actuator transforming electric pulse into angular displacement. Popularly, when receiving a pulse signal, the stepper motor will rotate a fixed angle (namely"stepping angle") according to the direction set for the stepper motor. The angular displacement volume can be controlled by controlling the pulse number to achieve the purpose of positioning accurately. In the meantime, the rotational velocity and acceleration of motor can be controlled by controlling the pulse frequency to achieve the purpose of speed control.

Laser marking machine can provide the most professional solutions in the laser marking area of the whole automotive industry, from the car body, car frame, hub and tire, various hardware components, central control of the seat, steering wheel and instrument panel, glass, interior decoration, lighting, the assorted oils for cars, ornaments and so on.

It depends on specific application situation, and to put it in a simple way: Nature of load (for example, vertical load or horizontal load), requirements of torque, inertia, speed, accuracy and acceleration and deceleration, requirements of upper control (such as requirements of port interface and communication), whether major controlling mode is position, torque or speed mode, whether power supply is direct or alternating current power supply, or battery powered, and voltage scope. Based on this, we can determine models of motor and supporting drives or controllers.

The fluid dispensing machine can be used for adhesive application in most industrial fluids. Most of fluid dispensing machines use stepping drive system, which has low working efficiency and cannot meet manufacturing requirements in some conditions. Using high quality dispensing system can avoid the impacts on quality and productivity of products. Therefore, based on the advantages, AC servo system with motion controller applied to the fluid dispensing machines to improve the quality and efficiency.

The traditional industrial agitator usually conducts no regulation or regulates the speed in mechanical method. The speed regulation in mechanical method will increase the loss of the industrial agitator. Meanwhile, the industrial agitator will work in fluctuating status. Furthermore, it will also work in the status of "big rated power with small load power", which is quite not economic. The motor power of the industrial agitator in operating under the frequency conversion speed control is similar to its characteristics of the revolving speed and pump load. Using VFD for speed regulation will obtain a substantial power saving rate.

When people are purchasing the laser equipment like the fiber laser marking machine, they will find that at present, there are many companies in the laser marking industry. Moreover, these big or small companies will quote different prices. Therefore, people may get confused in buying a laser marking machine. They don’t know where to start.

Unipolar and bipolar driver architectures are most commonly used for stepper motors.
Unipolar stepper motor indicates the stepper motor with 2 coils and 5 or 6 lines. That is, one tap is increased in the middle of one coil. 5 lines can be seen as 6 ones. The two intermediate line of two coils can be connected. For there is tap in the middle of one coil, the current can flow towards different direction along the half way in one coil, but half of the motor coil is just used.
Bipolar stepper motor indicates the stepper motor with 2 coils and 4 lines. The current can flow in forward and reverse direction in two coils, so called bipolarity.

Nowadays, with the continuous development of technology, AC servo motor technology gradually replaced the DC motor as the leading executive motor with its excellent cost performance. The mature technology of AC servo system also makes the market develop rapidly and become one of the supporting technologies of industrial automation. So what are the main functions of servo system and how is it classified? Continue and you will learn about that.

Rewinding machine is widely in the re-winding operation and inspection operation of the material in plastics, printing, composite, coating, bag making, and coating film. With double servo automatic tension control, it can operate in the positive and reverse direction. At the same time, it has the fixed point memory stop function, which can quickly reverse to the defect position. The equipment is composed of the unreeling mechanism, take-up mechanism, deviation rectifying device, material delivery guide roller, photoelectric device, tension detection, synchronous strobeflash, length detection, operation interface, electrical control and other parts.

Motion controller usually adapts two types of command mode to control servo motor:
Digital pulse
This mode is similar to the control mode of stepper motor. The motion controller sends"pulse/direction" type pulse command signal to servo driver, when servo driver operates in position control mode, position closed loop is completed by servo driver. This mode of servo motor has the advantages that system debugging is simple and is difficult to cause interference, but has the disadvantage that the response of servo system is slightly slow.
Analog signal
In this mode, motion control system sends/-10V analog voltage command to servo driver and receives position feedback signals from position detection elements, such as motor encoder or linear grating, etc., when servo driver operates in speed control mode, position closed loop is completed by motion controller. Europe and America servo products mostly adapt such operation mode, which has the advantage that response of servo is rapid, but the disadvantage is that they are sensitive to site interference and debugging is complex.

There are some notes for the users when installing and using the servo motor. Take care of servo motor and it can work better and longer. The article briefly illustrates some precations for installation and usage of servo motor from serveral aspects: oil and mater resistant protection, tension reduction for servo motor cable, allowable shaft terminal load and so on.

1. Servo motor does not run when the pulse is output, how to solve the problem?

1. Monitor the current pulse output value of controller and check if pulse output indicator lamp flashes to confirm 
   that the controller has performed command pulse and has output pulse normally.
2. Check if the control cable, power cable, encoder cable between controller and driver are matched incorrectly damaged or contacted poorly.
3. Check if the brake of servo motor equipped with brake has been turned on.
4. Monitor the panel of servo driver to confirm if the pulse command has been input.
5. Run command is normal.
6. For control mode, always choose position control mode.
7. Check if the type of input pulse set by servo driver matches with that of command pulse.
8. Ensure that positive side drive prohibition, negative side drive prohibition signals and deviation counter reset 
   signal are not input and the servo motor runs normally if load is removed, then check the mechanical system.

As the executive element of mechanical equipment, servo motor is used widely in servo system. When using servo motor, there is a phonomena of overheating when working. As you are not familiar with the principle and structure of servo motor, how to judge whether the heating value is normal or not? And how to reduce the heating value of servo motor?

Users often feel confused about the three braking ways of servo motor: electromagnetic braking, regenerative braking, and dynamic braking. As a result, they selected the wrong accessories. The article will tell you the differences among them and give some tips about the accessories selection.

One of the most significant advantages of stepper motor is that it can be controlled accurately in open loop system because the rotor position can be determined only by tracking the input step pulse, but overheating problem occurs easily in stepper motor, so how to solve this problem if such condition occurs?

In the specific occasion, when the terminal load is stable, the action is simple and the motor basically runs at low speed, it is appropriate to choose the stepper motor with low cost and easily controlling. However, when terminal load fluctuation range is large, action is simple and the motor basically runs at low speed, if still choosing the stepper motor, a series of troubles are coming. In fact, in such situation, servo motor should be chosen, as the comprehensive cost will decline considering many factors.