Trapezoidal Function; Din 40839 Function - Elektro-Automatik ELR 9000 Betriebsanleitung

3.9.8

Trapezoidal function

The following parameters can be configured for a trapezoidal curve function:
Value Range
I(A), U(A) 0...(Nominal value - (Off)) of U, I
I(Off), U(Off) 0...(Nominal value - (A)) of U, I
t1 0.1 ms...36000 s
t2 0.1 ms...36000 s
t3 0.1 ms...36000 s
t4 0.1 ms...36000 s
Schematic diagram:
A
t2 t3 t4
3.9.9

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.
The following parameters can be configured for the DIN40839 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 0.1 ms...36000 s
Schematic diagram:
A
1 2 3 4
Sequences
EA Elektro-Automatik GmbH
Helmholtzstr. 31-33 • 41747 Viersen
Germany
Description
A = Amplitude of the signal to be generated
Off = 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
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
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 different
by setting different times for gain and decay.
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.
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 requirement for the source is that it features
(an adjustable) current limitation.
The curve conforms to test impulse 4 of the DIN. With
suitable settings, other test impulses can be simulated.
If the curve in sequence 4 should be a sine wave, then
these 5 sequences would have to be reconstructed using
the arbitrary generator.
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ELR 9000 Series
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