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78
t
4Tsw
f
10
100
1000
10000
sweep
[Hz]
1
3Tsw
2Tsw
1Tsw
sweep
[s]
t1
T
Ampl.
[%]
0
100
20%
t2
z.B. 90 %
t
t1
T
Ampl.
[%]
0
100
20%
t2
t
50 %
Dreieckfunktion
Rechteckfunktion
Attention:
Do not activate trigger function in sweep mode (trgedge =0).
8.7 output of trigger signals
Trigger signals allow us to get an electrical signal when a position is reached or crossed. The
trigger points refer to the measured value (stroke or tilt). The trigger is low-active, i.e. a high/low
edge shows that you have reached a trigger point.
The active stroke/tilt-range for trigger
generation is given by “trgss” (start (lower) position) and
“trgse” (end (upper) position). The interval between the trigger points is given by “trgsi”. It is
possible to get trigger signals at the rising edge (trgedge,1), the falling edge (trgedge,2) or both
edges (trgedge,3).
To disable the trigger generation set trgedge,0. The measurement unit for trgss, trgse, trgsi is the
actuator specific unit (e.g. µm or mrad), the length of a trigger signal can be set to multiples of 20
µs (standard is 1*20 µs).
Take care that is there no overlap between two trigger impulses. If this occurs, you must minimize
the length of the impulses (trglen,1), or decrease the movement speed of the actuator.
Furthermore, you must be sure that the trigger range (between trgss and trgse) passes through
plus 0.2% of the total stroke, otherwise no trigger will be generated because no change between
the rising and falling edges will be detected. The points start, end and interval must be set, that the
calculation
(endpoint - startpoint) / interval
gives a integer number n without a remainder. The
counts of output trigger is given to n+1.
Attention:
Do not activate trigger function in sweep mode.
The amplitude that has been selected is the
peak to peak value. The sweep depth is
fixed by 0.1Hz to 10kHz (5 decades). In the
meantime,
the
frequency
increases
logarithmically.This case represents the
"sweep" parameter of the increasing
frequency per decade.
Attention:
It is not possible to calculate the waveform
in real time, but it will be calculated when
activate the sweep generator an stored in
memory.
Depending
on
parameter
sweeptime, it can be take few seconds.
When change the sweep time, initiate a new
calculation of values by switching off and on
the sweep generator (gfkt).
The symmetry of a signal
describes, in the case of the
triangular function, the ratio of
rise time t to time period T.
Based on this, a variation can
be introduced between a fast
increase and a slow decrease
as well as a slow increase and
a fast decrease of the function.
By
using
the
rectangular
function, the duty cycle of high
signal in relation to time of a
period is described.
triangle function
rectangle function
