Danfoss VLT Series Programming Manual page 128

Operation with ISD Toolbox
In the example depicted in Illustration 5.29, the real-time
task sampling is 8 kHz (125 µs between 2 samples), the
fast task sampling is 4 kHz (250 µs between 2 samples),
and the slow task sampling is 2 kHz (500 µs between 2
samples). These sampling rates are also shown for offline
devices.
The Subsampling field controls the subsampling level of
the trace, which is a factor applied to the sampling rate:
for example, using a fast task sampling with 250 µs
between 2 samples and subsampling 3, the resulting trace
has 750 µs between 2 samples.
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The field Samples controls the length of the trace in terms
of the number of sample counts per channel. The
maximum number allowed depends on the trace buffer of
the device and the number of channels to trace. For
example, if a device can trace a total maximum of 32000
samples and 4 channels are configured to be traced, then
the maximum number of samples per channel is 8000.
5.7.3.2 Triggering
The triggering functionality of the devices is visualized by
the Triggering control on the left side of the Scope. Specify
here whether the trace should be triggered by a certain
event, or if the trace should be started instantly.
Due to its real-time nature, the triggering functionality is
entirely implemented on the devices – the Scope only
controls and visualizes the triggering configuration on the
devices and does not implement any triggering logic.
A trigger event is defined by a trace signal, whose value is
exceeded in a positive or negative direction.
Illustration 5.30 shows an example of a trigger event that is
defined by the trace signal Cam pos set exceeding the
value of 180 degrees in a positive direction (rising slope).
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5
Illustration 5.30 Triggering Control
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®
VLT Integrated Servo Drive ISD
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Danfoss A/S © 01/2017 All rights reserved.
®
510 System
Callout Field Description
name
1 Signal Drop-down
list of
trigger
signals
2 Triggering Checkbox to
enabled enable/
disable
triggering
3 Slope Trigger
slope
4 Pretrigger Pretrigger
5 Level Trigger level Shows the value at which the
Table 5.8 Legend to Illustration 5.30
Function
Contains all available signals
on the device and selects the
signal to be used for
triggering. The behavior of the
Signal drop-down list is
exactly the same as the
behavior of the Signal name
drop-down list in the Signal
chooser control. It is not
necessary to also trace the
trigger signal.
Controls whether triggering
should be used on the device.
If triggering is disabled, then
the trace is started instantly
after activation (pressing the
Run button). Also, all other
fields of the Triggering control
are disabled.
Controls the direction from
which the Level value should
be reached in order for the
trace to be triggered: a rising
slope means that the value
should be reached in a
positive direction, and a falling
slope means that the value
should be reached in a
negative direction. The default
value of the button is rising.
Sets the number of samples to
be traced before the trigger
event occurs. The value is
given as a percentage of the
number of samples per
channel (field Samples). The
default value of the field is
10%.
trace should be triggered
(depending on the trigger
slope configuration). If
defined, the unit of the
selected trace signal is shown
on the right of the Level field.
The trigger level field is a
decimal value with 2 decimal
places. The default value of
the field is 0.
MG36D102