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LinMot
5.12.4 Oscilloscope configuration for the following error monitoring
User Manual V1.01
With the Zoom buttons under "Display" you can change curve sections and graph
scaling. The "Fit View" button restores the display as shown in the previous section.
When "Multi Shot" is selected under "Acquire", a new recording is started as soon as
the next trigger comes. This happens until the "Shot" button is clicked. "Shot" can be
clicked manually when an error that should be analyzed occurs.
Two other modes are available under "Mode" in "Acquire": "Normal" and
"Pretriggered". In the "Normal" mode the start delay is 0 s while in the "Pretriggered"
mode values are been recorded already before the actual trigger. It is important to note,
that in the "Pretriggered" mode enough time must have elapsed between the moment the
"Start" button was clicked and the actual trigger signal. Only in this case all the values
are valid. If this time is too short, the buffer could still contain data from a previous
recording. The minimal time that should elapse, can be calculated from the sample rate,
the pretrigger value and the information that 100% corresponds to 256 samples.
In the first example we have seen how a recording can be triggered by a regular signal,
such as the curve beginning. In this example we want to take a look at how to display
exceptional events, such as warnings and errors.
In order to reduce the changes to a minimum we will use the same motor with the same
configuration. We want to record the movements of the motor in a case of following
error.
On channel A we leave the setting "Actual Pos" to "Drive A", while on channel B we
select "Demand Pos Filtered" on "Drive A". "Demand Pos" is the position set value that
is read directly from the reference curve. As the set values are limited by the maximum
allowed speed and acceleration settings, "Demand Pos Filtered" represents the values
that are actually used by the motor controller. The speed and acceleration limiters can be
enabled, disabled and configured in the parameter tree.
As a next step we choose the trigger source. We set the "Trigger Mode" to "Trig on bit"
and select "Follow Warning", "Drive A" as "Var". We select "Up" for the active edge.
This way the recording will start when a following error occurs on motor A.
We switch to the entry fields under "Acquire" and leave the sample rate at 4000 µs, but
we set the mode to "Pretriggered" and "Pretrigger" at 20%. 20% of the recorded values
will represent a recording of the signals before the trigger.
We now want to test how the Oscilloscope behaves with these settings. For this purpose
we start the motor (by clicking "Start" in the Control Panel). When the motor executes
the curve, we start the recording with the Oscilloscope. The message "Waiting for
trigger" appears. If we hold the slider or force it to some position the recording will
start. Again, it takes some time before the values are read. Click "Fit View" and the
graphs obtained could appear as follows:
Configuration Software
5-27
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