If the panel and S7 PLC are not communicating, a common symptom is that the IO field displays "#####" in the image. If you cannot establish a communication connection with the PLC, follow these steps to troubleshoot:
1. Check the cable used
• For PPI/MPI/Profibus communication with S7-200/300/400, use an MPI cable (pins at both ends correspond to: 3-3, 4-4, 5-5, 8-8) or a Profibus cable (pins at both ends correspond to: 3-3, 8-8).
• It's recommended to use Siemens Purple Profibus cables and Profibus bus connectors (or DP connectors).
• You can also use a self-made shielded twisted pair cable, but ensure proper shielding and grounding. Siemens does not guarantee or support homemade cables.
• If using a DP connector to connect multiple stations on the network, make sure the terminating resistor is set correctly: ON for the two end connectors, OFF for the middle ones. See Figure 1.
Figure 1
2. Confirm the settings of the PLC communication port
• Ensure the baud rate is consistent across all devices.
• Make sure station addresses do not conflict.
• Use the same communication protocol on both ends.
3. Verify the communication settings in Portal and WinCC Flexible
• The peer device address must match the actual PLC station address. Note: For S7-300/400, set the slot number to match the one configured in Step7 hardware.
• The OP address should be unique and not overlap with any other device on the network.
• The baud rate must match the one set on the PLC.
Figure 2
• The profile must align with the network protocol. When communicating with S7-200, the panel has multiple options, and the PLC adapts to the protocol automatically. No need to set it in MicroWin—just configure the port and baud rate in the system block.
Figure 3
• Select "Unique master on bus."
4. Check if the panel’s communication port is used properly
• The IF1B port is used for PPI/MPI/Profibus communication with S7-200/300/400. The IF1B dial switch on the back of the panel should be factory-set and turned OFF.
5. Review system alarm information
To further diagnose communication issues, add the "Alarm View" object to the touch screen template during commissioning. This allows you to view system alarm messages. Check the "System" category under the "General" property "Alarm Events."
Figure 4
After activating the project on the panel, you can see the number of system alarm messages.
Figure 5
In the configuration software, go to "Options" > "Settings" > "Workbench" and set it to display all items. "System Events" will appear under the "Alarm Management" directory tree.
Figure 6
You can view system alarm messages corresponding to each alarm number through "System Events" in "Alarm Management." Once you identify the specific message number, you can address the issue more effectively.
Figure 7
For solutions to various message numbers, refer to the appendix in this link: A.2 System Alarm 26248558.
Figure 8
Additionally, make sure to:
• Power cycle both the panel and the PLC.
• Replace the Profibus cable with a new one.
The new product uses N-type TOPCon technology and is fully enhanced in performance, power, energy density and reliability.
The mass production efficiency of Sunket N-type TOPCon cells has reached 24.5%, the bifacial ratio of modules is up to 85%, and the additional power generation gain has increased by more than 3%. In 2022, Sunket will continue to focus on improving the efficiency of mass production of batteries, leading the efficiency and economy of TOPCon Series products to a new high, and bringing customers higher installed capacity.
TOPCON Solar, TOPCON Solar Panel, TOPCON Solar PV Module, TOPCON PV Module, TOPCON Solar Module
Wuxi Sunket New Energy Technology Co.,Ltd , https://www.sunketsolar.com