Visible PLC faults: 1. Module shows a red light (restart the module; if it still shows red after restarting, replace the PLC module. When replacing, the wiring plug does not need to be changed; just unplug the old module and plug in the new one). 2. All devices in the centralized control cannot start. First, … Read more
‖ System Learning Life is like a marathon; occasionally stopping to fish allows you to go further. In the modern industrial automation field, Programmable Logic Controllers (PLC) serve as the core of control systems, with the global market expected to reach $15.8 billion by 2025. From automotive manufacturing to energy management, PLCs control 80% of … Read more
1. What is a PLC? Let’s first look at its “physical structure”. To understand the working principle of a PLC, we must first recognize its hardware components. Just as humans operate with a “brain + senses + limbs”, a PLC also has three core parts: Input Module acts like the “senses”, responsible for receiving external … Read more
In the complex power and auxiliary systems of ships, temperature monitoring is crucial, directly affecting the safety of navigation and the lifespan of mechanical equipment. Thermocouples and resistance temperature detectors (RTDs) are two common types of temperature sensors found on ships, widely used in key areas such as main engines, auxiliary engines, boilers, and liquid … Read more
1. Overview The digital input interface of a PLC is not complex. To enhance anti-interference capability, PLCs use optocouplers to isolate the input signals from the internal processing circuits. Therefore, the signal at the input end only needs to drive the internal LED of the optocoupler to turn on, and the phototransistor of the optocoupler … Read more
Recently, the Electrical Instrumentation Workshop collaborated with the Materials and Equipment Department to invite senior technical experts from Siemens to successfully hold a week-long “PLC Automation System and Operations Maintenance Specialized Training”. All technical backbones of the Electrical Instrumentation Workshop participated, effectively solidifying their professional foundation through systematic learning of cutting-edge core technologies, providing strong … Read more
Analog signals are the most basic process signals in automation process control systems, such as pressure, temperature, flow, etc. These signals are input forms that are transmitted through transmitters, converting the detected signals into standardized voltage and current signals, and sending these signals in real-time to the controller (PLC). PLCs convert these analog signals into … Read more
Chapter One: Differences Between FCS and DCS Traditional Method: A one-to-one I/O wiring method connects field devices to controllers. Fieldbus Technology: All field devices are connected using a single cable. Detailed Comparison of FCS and DCS Chapter Two: Differences Between DCS and PLC Currently, there is no strict boundary between DCS and PLC. Most people … Read more
1. Design Requirements: 1. There are five buzzers A, B, C, D, and E. When the host presses the buzzer start button (I0.0), the buzzer indicator light (Q0.0) lights up, and the buzzer prompt sound (Q0.1) rings for 3 seconds. Only after the prompt sound ends can the buzzers be pressed. 2. Pressing the buzzer … Read more
