When the built-in trend control isn't enough: an Advanced Trend CWC

The built-in WinCC Unified trend control is close, but for operators it is not quite there. Here is what we ship instead — a Custom Web Control built on HTML, JavaScript and Chart.js.

Real history from the tag logging archive

Up to eight tags on one chart, pulled straight from the archive WinCC is already writing. Not a live ring buffer that forgets everything on screen change — open the screen a week later and last week’s data is still there.

The whole interface is configurable on the screen

Title, trend names, line colours, Y range, refresh rate, light or dark theme — all manifest properties. Drop it on a screen, fill in the boxes, no script editing.

Setpoint arrows live on the chart

Each trend gets an optional SP value, shown as a labelled arrow at the right edge, colour-matched to its line. Set it to zero to hide it. The operator can tell at a glance whether the PV is at target.

Pick your window, page through history

Minute, hour or day resolution with a configurable span — 30 minutes, 12 hours, 7 days. Two buttons step back and forward through the archive, and a LIVE badge lights up when you are back at the present edge.

One-click CSV of the visible window

Whatever is on screen lands in a spreadsheet — one timestamp column, one column per trend. No “export entire log” dialog; just what you are looking at right now.

Deployment

It is a CWC zip: drop it in UserFiles\CustomControls, attach a small bridge script to its DataRequest event, set the logging-tag names on the screen, done.

WinCC Unified ships with a lot. When it does not have exactly what you need, the CWC path is shorter than people think — and working examples of this control’s simpler cousins are on our free downloads page.