Typical automation components

A modern packaging machine includes many automated tasks where a user does not have to do any physical work. Therefore, a lot of automation components are required to create the motion for the designed mechanics. Packaging machines are able to receive the packaged piece, form a suitable package and convey it forward to the next station or to the next packaging phase.

According to Opportunities for Automation Companies in the EMEA Packaging Machinery Industry – IMS, the description for automation components is divided into the following components which are introduced briefly with a picture after the description. [13]

1.8.1.1 PLC – Programmable Logic Controller

PLC is a microprocessor-based device used in discrete manufacturing for line and machinery controlling. The common programming language used is IEC 61131 based and the devices are RISC-based. [13] A normal system includes a CPU (Central Processing Unit), I/O’s (digital or analog input/output module) and a fieldbus card. The main component is the CPU and all the other components are options which can be added to expand the system. One CPU can handle 320 digital I/O points which after the needed I/O’s has to be decentralized and at the same time the same CPU supports up to four different types of fieldbuses [23].

Picture 9. ABB AC500 PLC with I/O and fieldbus options. [15]

1.8.1.2 Motor drives

A motor drive is a piece of equipment that can adjust the speed of a motor by controlling the frequency [13]. Motor drives are used more frequently after the development in techniques. The invention was released at the end of the 1970s when a 5,5 kW drive was the width of a normal human being and nearly two meters high.

Today, a modern drive (or frequency converter) has significantly decreased in size, now being a very small piece of equipment. A modern 5,5 kW drive is approximately 150 mm in height, 100 mm in width and 100 mm in depth. While the physical size of a drive has decreased a great deal, the technical features have increased in many ways. The most recent technical features in a drive are that they support many kinds

of fieldbuses, have some kind of integrated safety feature and the software can be modified by the user. [24]

Picture 10. ABB ACS355 frequency converter for motor speed controlling. [16]

1.8.1.3 Visualization components

Visualization components are for example operator terminals such as HMI (Human Machine Interfaces), displays that can show text and graphics and Industrial PC’s.

[13] HMI provides a practical user interface for machinery controlling. Usually a HMI includes a touch screen or push buttons where a user can follow desired variables and make changes to the configuration. Industrial PC’s are more complicated equipment because they are able to control a full machine, including several available options such as fieldbuses and I/O’s and in some cases IPC can be used to replace PLC [12].

Picture 11. ABB CP650 control panel. [16]

1.8.1.4 Motion control

Motion control includes servo motors containing an integrated feedback device, including brushed DC servo motors [13]. The range of servo motors is broad including many options for feedback. The feedback is usually selected depending on the need for accuracy, environment or price. The most versatile encoder type for feedback is the multi-turn absolute encoder because it is extremely precise and the shaft position information is genuine, even if the main supply is lost during the run.

Thus, it can be noted that the absolute encoder remembers its position permanently.

There are some weaknesses in absolute encoders because the principle is based on optical activity, which is not as robust as the principle in resolver feedback. A servo motor including resolver feedback can be mounted in harsh environments due to the better duration in the resolver. The principle in the resolver is based on an electromagnetic field surrounding the magnetic poles, and is therefore less vulnerable to external threats [12].

Picture 12. ABB MS-servo motor series with resolver feedback. [18]

Fully enclosed servo drives with a single power output that can control the current, speed or position of any servo motor are listed as motion control products. In multi-axis systems each drive is counted individually. [13] A modern servo drive has to have a position feedback because the repository is usually an application that needs to be very dynamic and accurate. A servo drive can be controlled via fieldbus, pulse train or digital or analog signals. [25]

Picture 13. ABB Microflex e150 servo drive with integrated EtherCat fieldbus. [19]

The remaining products under motion control are the stepper motors with or without feedback, 2-, 3- or 5-phase, hybrid and stepper motors with an integrated drive. If the drive is supplied separately it is considered a fully enclosed stepper drive or amplifier for the controlling of speed and position in stepper motors. [13]

Picture 14. ABB DSMS-series stepper motors with integrated drive. [20]

The fifth main component under motion control is the position controller. The definition of a position controller is that the structure is PLC-based, PC-based or a stand-alone type. In picture 15, a typical position controller provided by ABB is shown. Usually a position controller is able to run several axes at the same time by using I/O’s or a fieldbus. The power supply is not fed from the position controller but the information on desired speed, position or torque is. A position controller is connected to the drive which runs the motor. [21]

Picture 15. ABB NextMove e100 motion controller. [21]

1.8.1.5 Other automation products

The following components are listed under Other automation components:

Pneumatic components, hydraulic drives and valves, mechanical linear & rotary handling systems, machine-safety products, low-voltage products, machine-vision systems and other automation equipment.