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EPS Stromversorgung GmbH
Alter Postweg 101 • 86159 Augsburg
Germany
Fon: +49 821 / 570451-0
Fax: +49 821 / 570451-25
www.eps-germany.de
PSI 10000 4U Serie
3.10
The function generator
3.10.1
Introduction
The built-in
function generator
(short:
FG
) is able to create various signal forms and apply these to the set value
of voltage or current.
The standard functions are based on an
arbitrary generator
and directly accessible and configurable using man
-
ual control. For remote control, the fully customizable arbitrary generator replicates the functions with sequences
containing 8 parameters each.
Other functions, such as IU, PV or FC are based on an
XY generator
that works with a table of 4096 values which
are either loaded from an USB stick or calculated based upon adjustable parameters.
The following functions are retrievable, configurable and controllable:
Function
Short description
Sine wave
Sine wave generation with adjustable amplitude, offset and frequency
Triangle
Triangular wave signal generation with adjustable amplitude, offset, rise and fall times
Rectangular
Rectangular wave signal generation with adjustable amplitude, offset and duty cycle
Trapezoid
Trapezoidal wave signal generation with adjustable amplitude, offset, rise time, pulse time, fall
time, idle time
DIN 40839
Simulated automobile engine start curve according to DIN 40839 / EN ISO 7637, split into 5 curve
parts (sequence points), each with a start voltage, final voltage and time
Arbitrary
Generation of a process with up to
99
freely configurable curve points, each with a start and end
value (AC/DC), start and end frequency, phase angle and duration
Ramp
Generation of a linear rise or fall ramp with start and end values and time before and after the ramp
IU
XY generator, USB stick loadable current curve (value table, CSV)
PV, FC
Functions to simulate a solar panel (PV function) or fuel cells (FC function), both with table cal
-
culation based upon adjustable parameters, also for EN 50530
Whilst R mode is activated, access to the function generator isn’t available.
3.10.2
General
3.10.2.1
Limitations
The function generator is not accessible, neither for manual access nor for remote control, if resistance mode (R
mode, also called UIR) is active.
3.10.2.2
Principle
The power supply unit can’t be considered as high power function generator, because its power stages are only
post-connected to the FG. Thus the typical characteristics of a voltage and current source remain. Rise and fall
times, caused by capacitor charge/discharge, affect the resulting signal on the DC output. While the FG is able to
generate a sine wave with 1000 Hz or more, the power supply will never be able to follow the generated signal 1:1.
Depiction of principle:
Affect of the power supply on functions:
FG
PSI
DC out
+
--
C
The resulting wave on the DC output heavily depends on the frequency/period of the selected wave, its amplitude
and also the output capacitance. The effects of the power stages on the wave can only be partially compensated.
For example, the resulting wave form on the DC output could be improved by attaching and additional load (fixed
& ohmic or variable & electronic) to the actual one, which can significantly improve down-ramping.
