Hi, I'm the editor from Chuanhe Automation Academy. Today, I'd like to chat with some industrial control experts!
When discussing PROFINET bus, Siemens' complete solutions immediately come to mind. However, today we recommend a Siemens PLC paired with Hechuan's PN servo solution. Compared to Siemens' complete solution, Hechuan offers a more comprehensive motor product line, higher cost-effectiveness, and easier commissioning, making it a highly competitive solution.
PROFINET bus, or PN bus for short, is an open Ethernet standard for the automation industry. Launched by the PROFIBUS International Organization in 2000, it is a next-generation automation bus standard based on industrial Ethernet technology. Its functions include: real-time communication, distributed field devices, motion control, distributed automation, network installation, IT standards and information security, fault tolerance, and process automation—eight main modules.
Here we will focus on motion control, specifically how to use the PN bus and Siemens PLC to control the Hechuan PN servo motor to achieve motion control.
The PROFIdrive specification is a crucial part of the PN bus. As a bus specification, PROFIdrive defines six major application scenarios, from AC1 to AC6, as shown in the diagram below:
The lower the level, the lower the real-time performance of the control. Ordinary frequency converter control is for AC1/2, simple point-to-point motion control is for AC3, and for more advanced and complex applications such as path interpolation and multi-axis synchronization, there is a corresponding AC4 level to ensure the real-time performance of the entire motion control system. Hechuan's PN servo supports servo systems of AC4 level and above.
The specific supported messages are as follows:
Isn't it amazing? I bet everyone wants to see what Hechuan's servers look like!
Haha, are you all a little confused? Isn't this exactly the same as Hechuan's EtherCAT bus? Yes, both Hechuan's PN bus servo and EC bus servo are bus servos developed from the X6 series platform, only they have built-in communication chips with different bus protocols. The former was led by Siemens, and with the fierce competition in the industrial control market, Siemens became more open, thus giving rise to the PN bus servo compliant with the PROFIdrive specification. Hechuan saw this market opportunity and launched the X6ER PN bus servo. With a power range from 50W to 7.5kW, it can perfectly connect with upper-level PLCs supporting PROFINET buses, such as the S7-200 Smart, S7-1200, and S7-1500. We also offer a full range of motors, including 17-bit magnetic encoders and high-precision 23-bit absolute optical encoders, with a maximum speed of 6500rpm, providing customers with more competitive motion control solutions!
Alright, after all that talk, I'm sure you're all eager to get started. So let's officially introduce how to configure the X6ER as an S7-1500 IO Device, and how to control Hechuan's PN servo products using Siemens S7-1500 process objects via PN communication messages 3.
Before you start learning, you should prepare the following learning tools:
Initialization configuration
01. Create a new project
First, we create a new project, select the S7-1500 PLC model, find the corresponding order number, and then click on the project view in the lower left corner.
02. Install the GSD file for X6ER
Select the "Options" button in the menu bar, and then click "Manage General Station Description Files" in the drop-down menu. Select the downloaded GSD folder and click Install. (Please contact our technical staff for the GSD file, or download it from our Chuanhe Automation Academy website: http://class.hcfa.cn/)
03. Add X6ER device
Select "Devices and Networks" under the "Devices" view on the left, and then select HCFA X6FRV5.0 in the "Network Overview" on the right. Double-click or drag it to a blank area.
After clicking the unassigned selection "PLC_1PROFINET Interface_1" on the X6FR, a green connection will appear between the PLC and the X6FR. Note: The program configuration needs to be consistent with the actual connection. When using IRT isochronous mode, configuring the device connection topology is necessary.
04. Assign Equipment Name
Right-click on the X6FR device and select "Assign Device Name". On the pop-up page, click "Update Device". After finding the x6fr_1 device, click "Assign Name".
05. Message Selection
Double-click the X6FR device in the device and view interface. Under "Device Overview", we can see the currently configured messages of X6FR, as well as the supported messages under "Sub-modules" on the right.
Right-click on Standard Message 1 and select Delete, then double-click "Add Standard Message 3" on the right to add Message 3.
06. Add process objects
Select the "Add Object" button under "Process Objects" in the device tree to add a new process object for Axis1. Here, we'll use the positioning axis TO_PositioningAxis as an example.
07. Configure process objects
Configure the relevant parameters of the process object in the "Configuration" interface, and configure the type, position unit, and whether to simulate the axis in the basic parameter interface.
Configure the X6FR driver object, driver type, and data connection in the "Driver" interface.
In the encoder interface, select the encoder type, encoder, data connection, and encoder type: incremental system or absolute system.
On the "Data Exchange with Drive Unit" and "Data Exchange with Encoder Unit" pages, you can set data such as the maximum motor speed and drive unit messages. These settings can be done manually or by selecting "Automatically transmit device parameter values." We recommend selecting "Automatically transmit device parameter values."
The "Position Restriction" interface allows you to set the hardware limit switch and the soft limit position.
In the "Mechanical" interface, set the correspondence between the number of unit commands in the program and the number of motor revolutions. The 10mm/rot setting here means that 10mm corresponds to one revolution of the motor. The default unit in the program is mm.
II. Motion Control Programming
Under the device tree “PLC_1[CPU 1513-1 PN]”, select “MainOB1” in “Program Block” to enter the program editing interface.
Motion control programming can be performed using the "Motion Control" command in the process.
Add relevant motion control instructions to the program, such as MC_Power and MC_MOVEJOG, and assign the value of the process object Axis1 to the input/output pin Axis of each function block.
After completing the motion control program programming, click "Compile" in the menu bar. Once the diagnostic information shows no errors, select the "Download Program" button to download the program to the CPU.
After downloading the program, click "Go to Online" to monitor the program online. You can then change the input pins of the function block to complete the positioning control function.
After reviewing these steps, are your demos running smoothly? Isn't it simple? This is just a simple example of single-axis motion control. With your skills, I'm sure it's a breeze. Don't worry, in later articles we'll focus on how to use Siemens PLCs for multi-axis interpolation and other advanced motion control. Follow and bookmark our official WeChat account so you don't miss out!
