Automatic Light Curtain,Laser Light Curtain,Automation Light Beam Sensor,Automatic Infrared Beam Sensor,Infrared Beam Curttain Sensor,Infrared Beam Sensor Jining Keli Photoelectronic Industrial Co.,Ltd , https://www.sdkelien.com
The S7-300 PLC carries forward the traditional design features of Siemens' S series PLCs, offering a compact size, flexible configuration, and robust functionality. This makes it an ideal choice for thermal protection systems that require high precision, reliability, and completeness. Its advanced capabilities ensure accurate monitoring and control, making it well-suited for critical industrial applications.
The OP5 Operator Panel is a user-friendly man-machine interface developed by Siemens. It serves as a key tool for displaying and monitoring internal PLC information, allowing users to adjust PLC parameters using the panel's function keys. The panel primarily displays event and alarm messages, with alarms taking priority over regular events. When an alarm condition is met, any ongoing event display is replaced by a flashing alarm message, ensuring immediate attention from operators.
The SIMATIC programmable controller offers a wide range of convenient interfaces for the OP5. The panel can be directly connected to the S7 series PLC for real-time human-machine interaction or configured offline. The current OP series includes a text display device that shows numerical values or symbols, with functions and interfaces defined through the COROSProtool/Lite software in a Windows environment. Additionally, the O-shaped display device uses COROSProtool for defining its layout. Programmers can use familiar Windows-based tools like Designer, CorelDraw, or Paintbrush to create custom graphics, which are then converted into bitmap format for process visualization, such as bar charts or flow diagrams.
Based on the requirements of the Shentou No.1 Power Plant unit control system, the OP5 operator panel was designed with several key functions: automatic tour display, manual single-screen display, alarm display, protection activation and deactivation, system settings, system reset, and password protection. These features enhance operational efficiency and safety.
The protection system monitors critical thermal parameters of the furnace and issues early warnings or protection signals when limits are exceeded, prompting the operator to take action or shut down the system. To ensure reliable operation and prevent false signals, the system follows the signal processing characteristics of the Siemens S series PLC, where measurement signals must be validated before triggering an over-limit response.
To achieve this, the same thermal parameter is measured redundantly, with two input signals coming from the program control (left input) and the instrument (right input). Each signal undergoes validity checks for faults. Only valid signals are used for over-limit judgment. If a fault occurs, the system sends a fault status signal to alert personnel for quick troubleshooting.
The working principle and input/output logic of the protection system are as follows:
a. Input signals are first diagnosed for three types of faults: 1) exceeding the normal range (range fault), 2) exceeding the maximum rate of change (rate fault), and 3) either of the above indicating a channel fault. Once detected, these fault statuses are displayed and flashed on the OP5 panel, while also being sent to the central control console. Fault messages stop flashing only after being acknowledged on the OP5, but the fault details and time of occurrence are stored in the buffer for later review.
b. In case of a channel failure, the protection output is disabled. The fault status remains until the issue is resolved and the reset button is pressed, at which point the protection output is re-enabled.
c. After validating the input signals, the system checks for over-limit conditions. If the limit is exceeded, a forecast signal is issued after a 2-second delay (or based on left-right phase timing). If the protection limit is exceeded without a lockout, a protection signal is triggered after a 2-second delay (with left-right phase and 2-second delay).
d. During the 2-second delay period, if the forecast limit is restored, the delay is reset. Similarly, if the protection is closed or blocked, the delay is also reset.
In summary, the S7-300 PLC inherits the compact, flexible, and powerful design of the Siemens S series, making it highly suitable for thermal protection systems. With its OB35-based programming and enhanced fault diagnosis and protection logic, the system significantly reduces the risk of misoperation, far surpassing the previous relay-based hard-wired protection modules.
This Automation curtain is specially designed for automation industry. SDKELI LSC2 light curtain is designed for automation field, with small size, compact structure and strong anti-interference ability, and the product meets IEC 61496-2 standards. The automatic light curtain is with reliable quality and very competitive price. It has been used in many factories.
September 25, 2025