Line Trace

Overview

The Line Trace is a powerful UI component used to visualize live variable data in real time.
A trace is a more detailed and often shorter-term record of data, recording the current value and historical values of a datapoint-connection.

Note:
The data source (variable values or logged signals) is handled externally, typically through CODESYS or a connected PLC system.
The Line Trace in PLCVisu focuses on reading and displaying this data.

Key Features

  • Display of real-time data traces
  • Support for multiple variable channels

UI Sections & Configuration

Multi Connection

Each connection represents one variable being visualized.
Connections can be added or removed through the connection-picker.

General

Field Description
Title Label displayed above the graph

X-Axis

Field Description
X-Axis Label Label for the horizontal (time) axis
X-Axis Format Format of the time values:
- Relative Time (seconds since start)
- Absolute Time (real timestamps)
Max-Point Maximum number of points defined

Custom examples for X-Axis Format:

  • HH:mm:ss → shows hours, minutes, and seconds
  • DD:MM:YYYY → shows day, month, and year
  • YYYY-MM-DD HH:mm → full date with hour and minute

This format string follows standard time formatting rules. Adjust it to match the precision and structure needed for your data (e.g. for detailed logs, use seconds; for long-term traces, use date).

Y-Axis

Field Description
Y-Axis Label Label for the vertical axis
Y-Axis Min Minimum value of the displayed range
Y-Axis Max Maximum value of the displayed range

Data Flow Logic

Data Source

  • Data is read from a PLC, runtime system, or external variable database
  • No direct logging is done by the Line Trace itself

Data Display

  • The HMI continuously retrieves variable values and updates the trace
YYYY-MM-DD HH:mm
DD:MM:YYYY
HH:mm:ss