Easy PID Controller Node for Node-RED

The easy-pid-controller is a simple-to-use Node-RED node that provides Proportional-Integral-Derivative (PID) control functionalities. This node is designed to integrate easily with various control systems and offers configuration options for 0-10V and 4-20mA control signals.

Features

• Easy to configure PID parameters: Kp, Ki, Kd.
• Setpoint (SV) input for desired control level.
• Process Variable (PV) input to feedback the current state.
• Output values for PID components (P, I, D), final output signal, and mapped value signal.
• Choice of control signal types: 0-10V or 4-20mA.
• Real-time status updates during runtime for easier debugging and monitoring.

Installation

npm install node-red-contrib-easy-pid-controller

Usage

1. Drag and drop the easy-pid-controller node into your Node-RED flow.
2. Double click on the node to configure its parameters.
3. Connect it to other nodes to provide PV and SV inputs and get the output signals.
4. Deploy and monitor the control signal in real-time.

Inputs

• SV: The desired setpoint value for the controller. Previously was part of the node's configuration, now can be sent as a msg.payload with the topic SV.
• PV: The process variable or the current state of the system.
• auto: Boolean signal. If set to true, the PID loop starts.

Outputs

The node outputs an object payload containing:

• PV: The current process variable.
• SV: The setpoint.
• P, I, D: PID component values.
• Output: The final PID calculated signal.
• Value: The mapped control signal according to the sensor type (0-10V or 4-20mA).

Changelog

v1.2.1

• Added: Node status updates during runtime to display relevant information like current PV, PID activation state, and more.

v1.2.0

• Changed: Moved the Setpoint (SV) from node configuration to msg.payload with the topic SV.

v1.1.0

• Added: New output value Value that provides the direct control signal based on the sensor type configuration.
• Improved: Code documentation and error handling for invalid inputs.

v1.0.0

• Initial release with basic PID functionalities.
• Support for 0-10V and 4-20mA signal types.

Contributing

Contributions to improve the node or fix any issues are always welcome. Please submit a pull request on the GitHub repository.

License

GPL-3.0 License. See LICENSE file for details.

Example

Visit the examples/ directory for a sample flow illustrating the usage of the node.

Author

Harshad Joshi @ Bufferstack.IO Analytics Technology LLP, Pune