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EA Elektro-Automatik GmbH
Helmholtzstr. 31-37 • 41747 Viersen
Germany
Fon: +49 2162 / 3785-0
Fax: +49 2162 / 16230
www.elektroautomatik.de
PSB 9000 3U Series
3.11.8 Trapezoidal function
The following parameters can be configured for a trapezoidal curve function. Following applies:
•
There is no preselection to which of both, source mode and sink mode, the function is applied to; the settings
decide whether it is “source mode only”, “sink mode only” or a mixture of both
•
When applying the function to the voltage, the device can only switch to and work in sink mode if the external
voltage on the DC terminal is higher than the highest point ( amplitude) of the wave and the current set
-
ting “I Sink” is not 0
Value
Range
Description
U(A), I(A)
0...(rated value - [Offs])
A = Amplitude of the signal to be generated
U(Offs)
0... (U
Nom
- A)
Offs = Offset, based on the foot of the trapezium
I(Offs)
- (I
Nom
- A)...+(I
Nom
- A)
t1
0.1 ms...36000 s
Time for the positive slope of the trapezoidal wave signal.
t2
0.1 ms...36000 s
Time for the top value of the trapezoidal wave signal.
t3
0.1 ms...36000 s
Time for the negative slope of the trapezoidal wave signal.
t4
0.1 ms...36000 s
Time for the base value (=offset) of the trapezoidal wave signal
Schematic diagram:
Application and result:
O
ffse
t
t
A
A
m
plit
ud
e
t1
t2
t3
t4
Same as with other functions the generated signal can
be applied to the set value of voltage (U mode) or to the
current (I mode). The slopes of the trapezium can be dif-
ferent from each other by adjusting the times for rise and
fall accordingly.
The periodic duration and repetition frequency are the result
of the four adjustable time values. With suitable settings the
trapezium can be deformed to a triangular or rectangular
wave. It has, therefore, universal use.
3.11.9 DIN 40839 function
This function is based on the curve defined in DIN 40839 / EN ISO 7637 (test impulse 4), and is only applicable
to voltage. It shall replicate the progress of automobile battery voltage during engine starting. The curve is divided
into 5 sequences (see diagram below) which each have the same parameters. The standard values from the DIN
are set already as default values for the five sequences.
Typically, this function is used with power supplies (here: source mode), but can also be used with electronic loads
(here: sink mode). However, the device can only switch to and work in sink mode if the external voltage on the DC
terminal is higher than the highest point ( amplitude) of the wave and the external source cannot deliver
more current than the sink mode is able to draw according to the current rating. Else the device could regulate the
voltage values resulting from the curve.
The following parameters can be configured for the DIN40839 function:
Value
Range
Seq Description
Ustart
0...U
Nom
1-5
Start voltage of the ramp
Uend
0...U
Nom
1-5
End voltage of the ramp
Seq.time
0.1 ms...36000 s
1-5
Time of the ramp
Seq.cycles
∞ or 1...999
-
Number of repetitions of the entire curve
Time t1
0.1 ms...36000 s
-
Time after cycle before repetition (cycle <> 1)
