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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 9000 2U Series
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 manual
control. For remote control, the fully customisable arbitrary generator replicates the functions with sequences
containing 8 parameters each.
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
sequences, each with a start voltage, final voltage and time
Arbitrary
Generation of a process with up to 100 freely configurable curve points, each with a start and end
value (AC/DC), start and end frequency, phase angle and total duration
Ramp
Generation of a linear rise or fall ramp with start and end values and time before and after the ramp
UI, IU
PV, FC
Table (.csv) with values for U or I, uploaded from an USB stick, as well as functions to simulate a
solar panel (PV function) or fuel cells (FC function)
Whilst R mode is activated, access to the function generator is not 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 (U/R
adjustment, also called UIR operation) is active.
3.10.2.2 Principle
The power supply unit cannot be considered as high power function generator, because it is 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 form on the DC output heavily depends on the frequency of the selected wave, its amplitude
and power supply model. The effects of the power supply on the wave can only be partially compensated. A high-
speed modification, like offered with
option
HS
(see
), can help to decrease rise and fall times.
This has a positive impact on periodic functions like rectangle or sine wave. Alternatively, the resulting wave form
on the DC output can also be improved by attaching additional load (fixed & ohmic or variable & electronic).
