Command: Trigger Plot (102)

Supported Axes:

All

See the Commands Overview topic for basic command information and how to issue commands from PLCs, HMIs, etc.

Command Parameters

#	Parameter Description	Range
1	Plot Number	any valid plot number

Description

This command triggers a plot. Triggering a plot means to start a plot, and include plot data from before the moment at which plot was triggered. This is very useful for troubleshooting. For example, if a plot is triggered when an error occurs, the plot can show data from before the error occurred, giving the user insight as to what happened.

The amount of plot data included from before the trigger is defined by the Pre-Trigger Percent in the Plot Template Editor. The default Pre-Trigger Percent is 0%, which means no data from before the trigger will be included. In order to include data from before the trigger, the Pre-Trigger Percent must be greater than zero and the plot Rearm Mode in the Plot Template Editor must be set to Manual Rearm.

When the plot is set to Manual Rearm, the Rearm Plot (103) command must be issued before triggering the plot. Notice that rearming a plot will clear all previously captured data for that plot. If a plot is triggered immediately after rearming it, and the Pre-Trigger Percent is greater than 0%, the plot will not contain any data before the trigger. After rearming, there must be a delay long enough to record the data to fill the plot before the trigger time.

If the plot trigger has been disabled, this command will be ignored. The plot trigger is automatically disabled while in Trend Mode in the Plot Manager, or can be disabled with the Enable/Disable Plot Trigger (104) command.

This command differs from the Start Plot (100) commands in the following ways:

The Start Plot (100) command will start a plot that only includes data from after the Start Plot command was issued.
The Start Plot (100) command starts a new plot immediately, even if the specified Plot number is currently capturing a plot. The Trigger Plot (102) command will not trigger a plot if the specified Plot Number is currently capturing a plot.

Plots can also be triggered automatically when a motion command is issued to an axis. To find out more on triggering, see the Triggering Plots topic.