This Software Requirements Specification (SRS) document provides a comprehensive overview of the PLC control system developed using Node-RED. This document aims to define the system’s functionalities, requirements, constraints, and interactions to ensure a clear understanding among all stakeholders.
The PLC control system is designed to facilitate industrial automation by enabling operators to send commands to a Programmable Logic Controller (PLC). The system primarily focuses on buzzer control and crane operations. This SRS outlines the essential requirements for developing, testing, and maintaining the system.
- PLC: Programmable Logic Controller
- Node-RED: Flow-based development tool for visual programming
- SRS: Software Requirements Specification
- Node-RED Documentation: Node-RED Documentation
- Modbus Protocol Standards: Modbus Protocol
This document details the functional and non-functional requirements, system architecture, user interface, and maintenance aspects of the PLC control system.
The PLC control system integrates into the broader industrial automation ecosystem. It enables human operators to interact with automated processes through a user-friendly interface, ensuring efficient management and control of critical operations.
- Buzzer Control: Commands to activate and deactivate the buzzer.
- Crane Operations: Commands to stop and release the crane.
- User Interface: Intuitive dashboard for operators.
- Logging and Debugging: Detailed logs for monitoring and troubleshooting.
- Production Operators: Require an easy-to-use interface to control PLC operations.
- Control Engineers: Need access to detailed logs and system status for maintenance and troubleshooting.
- The system must be developed using Node-RED.
- Communication with the PLC must use the Modbus TCP protocol.
- The system must ensure high availability and security.
- Reliable network communication between Node-RED and the PLC.
- Users have basic training in operating the system.
- Description: The system must allow operators to clear the buzzer by sending a command to the PLC.
- Acceptance Criteria: The buzzer should be deactivated within 3 seconds of sending the command.
flowchart TD
Operator --> UserInterface
UserInterface --> NodeRED
NodeRED --> PLC
PLC --> Buzzer
- Description: The system must allow operators to stop the crane by sending a command to the PLC.
- Acceptance Criteria: The crane should stop within 3 seconds of sending the command.
flowchart TD
Operator --> UserInterface
UserInterface --> NodeRED
NodeRED --> PLC
PLC --> Crane
- Description: The system must allow operators to release the crane by sending a command to the PLC.
- Acceptance Criteria: The crane should be released within 3 seconds of sending the command.
flowchart TD
Operator --> UserInterface
UserInterface --> NodeRED
NodeRED --> PLC
PLC --> Crane
- Description: The system must process and send commands to the PLC within 1 second.
- Acceptance Criteria: Average command processing time should be below 1 second.
- Description: The system must maintain 99.9% uptime.
- Acceptance Criteria: System availability should be at least 99.9%.
- Description: The interface must be intuitive for production operators.
- Acceptance Criteria: Operators should be able to perform tasks with minimal training.
- Description: Only authorized users should be able to send critical commands.
- Acceptance Criteria: Authentication and access control must be implemented.
flowchart TD
Operator --> UserInterface
UserInterface --> CommandNodes
CommandNodes --> DelayNodes
DelayNodes --> DebugNodes
DebugNodes --> PLC
PLC --> Devices
sequenceDiagram
participant Operator
participant UserInterface
participant NodeRED
participant PLC
Operator ->> UserInterface: Send Command
UserInterface ->> NodeRED: Forward Command
NodeRED ->> PLC: Send Command
PLC ->> NodeRED: Acknowledge Command
NodeRED ->> UserInterface: Update Status
UserInterface ->> Operator: Display Status
classDiagram
class UserInterface {
+sendCommand(command)
+updateStatus(status)
}
class CommandNode {
+processCommand(command)
+sendToPLC(command)
}
class DelayNode {
+addDelay(duration)
}
class DebugNode {
+logStatus(status)
}
class PLC {
+receiveCommand(command)
+sendStatus()
}
UserInterface -- CommandNode
CommandNode -- DelayNode
DelayNode -- DebugNode
DebugNode -- PLC
erDiagram
USER {
int user_id
string name
string role
}
COMMAND {
int command_id
string type
string status
}
LOG {
int log_id
string message
datetime timestamp
}
USER ||--o{ COMMAND: sends
COMMAND ||--o{ LOG: generates
The user interface is designed to be intuitive and user-friendly, allowing operators to send commands and monitor system status with ease. It consists of the following components:
- Dashboard: Displays real-time status of the PLC and connected devices.
- Command Panel: Allows operators to send commands to the PLC.
- Log Panel: Shows detailed logs for debugging and monitoring.
journey
title User Journey for PLC Control System
section Sending a Command
Operator: 5: Open the User Interface
Operator: 5: Select Command to Send
Operator: 5: Confirm and Send Command
section Monitoring Status
Operator: 4: View Real-Time Status on Dashboard
Operator: 4: Check Logs for Command Acknowledgment
section Troubleshooting
Engineer: 4: Access Log Panel
Engineer: 3: Analyze Logs for Errors
Engineer: 4: Perform Necessary Troubleshooting
The user interface is built using HTML, CSS, and JavaScript to provide a responsive and interactive experience. The HTML components are designed to integrate seamlessly with Node-RED, enabling real-time updates and command execution.
- Dashboard: Displays real-time data and status indicators.
- Command Panel: Provides buttons and input fields for sending commands.
- Log Panel: Displays logs and system messages for monitoring and debugging.
The system includes comprehensive logging and monitoring capabilities to track command execution and system status. Logs are accessible through the user interface and can be exported for further analysis.
Regular updates and upgrades will be provided to ensure the system remains secure and up-to-date with the latest features and improvements.
Technical support is available to assist with any issues or questions related to the system. Support includes troubleshooting, bug fixes, and guidance on system usage.
- PLC: Programmable Logic Controller
- Node-RED: Flow-based development tool for visual programming
- Modbus: Communication protocol used with PLCs
- Node-RED Documentation: Node-RED Documentation
- Modbus Protocol Standards: Modbus Protocol
This concludes the Software Requirements Specification for the PLC control system.