Elektro-Automatik PSI 9000 DT Series, Руководство по эксплуатации

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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
ea1974@elektroautomatik.de
PSI 9000 DT 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 them to the set value
of voltage or current.
All functions are based on a customisable
arbitrary generator. In manual operation, the separate functions are
available for selection and configuration on the front panel. In remote control, all functions are configured using
so-called sequences with 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 99 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
Whilst R mode is activated, access to the function generator isn’t available.
3.10.2 General
3.10.2.1 Restrictions
The function generator isn’t accessible, neither for manual access nor for remote control, if
• resistance mode (R/I adjustment mode, also called UIR mode) is active.
3.10.2.2 Principle
The power supply unit can’t be considered as a high power function generator, because it’s 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 the output capacitance. The effects of the power supply on the wave can only be partially compensated. For
instance, it’s possible to decrease the output voltage sinking time at low load conditions by adding a base load,
one that is either permanently connected or temporarily switched.
The minimum values of all adjustable parameters of the function generator, like for example
a time of 0.1 ms, are not defined to match what a power supply device resp. every particular
model can truly achieve.
3.10.2.3 Possible technical complications
Operation of switching mode power supplies as a voltage source can, when applying a function to the output volt-
age, lead to damage of the output capacitors due to continuous charging/discharging which causes overheating.