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www.elektroautomatik.de
EL 9000 B 15U/24U Series
3.10.10 Arbitrary function
The arbitrary (freely definable) function offers the user further scope. There are 99 sequence points available for
use on either current (I) or voltage (U), all of which have the same set of parameters but which can be differently
configured, so that a complex function process can be built up. The 99 points can run one after another in a block,
and this block can then be repeated many times or endlessly. A point or a block controls either current or voltage,
thus a mix of assignment to current (I) or voltage (U) is not possible.
The arbitrary curve overlays a linear progression (DC) with a sine curve (AC), whose amplitude and frequency are
shaped between start and end values. If the start frequency (fs) = end frequency (fe) = 0 Hz, the AC values have
no impact and only the DC part is effective. Each sequence point is allocated a sequence point time in which the
AC/DC curve from start to finish will be generated.
The following parameters can be configured for each sequence point in the arbitrary function. The table lists pa
-
rameters for current, for voltage it would be Us, Ue etc.:
Value
Range
Description
Is(AC)
0...50% Nominal value of I
Start amplitude of the sine wave part of the curve (AC)
Ie(AC)
0...50% Nominal value of I
End amplitude of the sine wave part of the curve (AC)
fs(1/T)
0 Hz...10000 Hz
Start frequency of the sine wave part of the curve (AC)
fe(1/T)
0 Hz...10000 Hz
End frequency of the sine wave part of the curve (AC)
Angle
0°...359°
Start angle of the sine wave part of the curve (AC)
Is(DC)
Is(AC)...(Nominal value - Is(AC)) of I
Start value of the DC part of the curve
Ie(DC)
Ie(AC)...(Nominal value - Ie(AC)) of I
End value of the DC part of the curve
Seq.time 0.01 ms...36000 s
Time for the selected sequence point
The sequence point time (seq. time) and the start and end frequency are related. The minimum
value for
Δ
f/s is 9.3. Thus, for example, a setting of fs = 1 Hz, fe = 11 Hz and Seq.time = 5 s
would not be accepted as
Δ
f/s is only 2. A seq. time of 1 s would be accepted, or, if the time
remains at 5 s, then fe = 51 Hz must be set.
The amplitude change between start and end is related to the sequence point time. A minimal
change over an extended time is not possible and in such a case the device will report an inap-
plicable setting.
After the settings for the selected sequence points are accepted with SAVE, further ones can be configured. If the
button NEXT is touched a second settings screen appears in which global settings for all points are displayed.
The following parameters can be set for the total run of an arbitrary function:
Value
Range
Description
Start seq.
1...End seq.
First sequence point in the sequence point block
End seq.
Start seq...99
Last sequence point in the sequence point block
Seq. Cycles ∞ or 1...999
Number of cycles of the sequence point block.
Schematic diagram:
Applications and results:
St
ar
t(
D
C
)
t
A
St
art
(A
C)
Seq.time
En
d
(D
C
)
Example 1
Focussing 1 cycle of 1 sequence point from 99:
DC values for start and end are the same, also the AC amplitude.
With a frequency >0 a sine wave progression of the set value is
generated with a defined amplitude, frequency and Y shift (offset,
DC value at start and end)
The number of sine waves per cycle depend on the sequence point
time and the frequency. If the time were 1 s and the frequency 1 Hz,
there would be exactly 1 sine wave. If the time were 0.5 s at the same
frequency, there would only be a half sine wave.
