Trapezoidal Function; Din 40839 Function - Elektro-Automatik EL 9080-170 B Betriebsanleitung

3.10.8

Trapezoidal function

The following parameters can be configured for a trapezoidal curve function:
Value Range
I(A), U(A) 0...(Nominal value - (Offs)) of U, I A = Amplitude of the signal to be generated
I(Offs), U(Offs) 0...(Nominal value - (A)) of U, I
t1 0.01 ms...36000 s
t2 0.01 ms...36000 s
t3 0.01 ms...36000 s
t4 0.01 ms...36000 s
Schematic diagram:
A
t2 t3 t4
3.10.9

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 segments (or sequence points), see diagram below, which each have the same parameters. The standard
values from the DIN are set already as default values for the five sequence points.
The following parameters can be configured for the DIN 40839 function:
Value Range
Ustart 0...Nominal value of U
Uend 0...Nominal value of U
Seq.time 0.1 ms...36000 s
Seq.cycles ∞ or 1...999
Time t1 0.01 ms...36000 s
Schematic diagram:
A
1 2 3 4
Sequence points
EA Elektro-Automatik GmbH
Helmholtzstr. 31-37 • 41747 Viersen
Germany
Description
Offs = Offset, based on the foot of the trapezium
Time for the negative slope of the trapezoidal wave signal
Time for the top value of the trapezoidal wave signal
Time for the negative slope of the trapezoidal wave signal
Time for the base value (offset) of the trapezoidal wave signal
Application and result:
Here a trapezoidal signal can be applied to a set value of U
or I. The slopes of the trapezium can be varied by setting dif-
ferent times for rise and fall.
The periodic duration and repeat frequency are the result
of four time elements. With suitable settings the trapezium
can be deformed to a triangular or rectangular wave. It has,
therefore, universal use.
t
t1
Seq Description
1-5 Start voltage of the ramp
1-5 End voltage of the ramp
1-5 Time of the ramp
- Number of repetitions of the entire curve
- Time after cycle before repetition (cycle <> 1)
t
5 t1
Fon: +49 2162 / 3785-0
Fax: +49 2162 / 16230
When adjusting very short time values for
t1 not every adjustable amplitude can be
gained on the DC input. Rule of thumb:
the smaller the time value, the lower the
true amplitude.
Application and result:
The function's primary use is to load a source, i. e. power
supply, which cannot generate the curve itself and would
supply a static DC voltage. The load acts as a sink for the
rapid fall of the output voltage of the power supply enabling
the voltage progress to follow the DIN curve. The only re-
quirement for the source is that it features (an adjustable)
current limitation.
The curve conforms to test impulse 4 of the DIN. With suit-
able settings, other test impulses can be simulated. If the
curve in sequence point 4 should be a sine wave, then these
5 sequence points would have to be reconstructed using
the arbitrary generator.
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EL 9000 B Series
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