User manual

Page 59
EA Elektro-Automatik GmbH
Helmholtzstr. 31-37 • 41747 Viersen
Germany
Fon: +49 2162 / 3785-0
Fax: +49 2162 / 16230
www.elektroautomatik.de
[e-mail]
EL 9000 B HP Series
3.10 The function generator
3.10.1 Introduction
The built-in function generator 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congurableusingmanual
control. For remote control, the fully customisable arbitrary generator replicates the functions with sequences
containing 8 parameters each. Further functions, such as UI-IU, are bases on a table with 4096 values, working
as XY function. Battery test and MPP tracking are software based functions only.
Thefollowingfunctionsareretrievable,congurable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,nalvoltageandtime
Arbitrary Generationofaprocesswithupto100freelycongurablesteps,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 Table (.csv) with values for U or I, uploaded from an USB stick
Battery test Battery discharge test with constant or pulsed current, along with Ah, Wh and time counters
MPP Tracking Simulationofthecharacteristictrackingbehaviourofsolarinverterswhenseekingtondthe
maximum power point (MPP) when being connected to typical sources such as solar panels
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/I
adjustment mode, also called UIR mode) is active.
3.10.3 Method of operation
In order to understand how the function generator works and how the value settings interact, the following should
be noted:
The device operates always with the three set values U,I and P, also in function generator mode.
The selected function can be used on one of the values U or I, the other two are then constants and have a limit-
ing effect. That means, if, e.g. a voltage of 10 V is applied to the DC input and a sine wave function should oper-
ate on the current with an amplitude of 20 A and offset 20 A, then the function generator will create a sine wave
progression of current between 0 A (min) and 40 A (max), which will result in an input power between 0 W (min)
and 400 W (max).The input power, however, is limited to its set value. If this were 300 W then, in this case, the
current would be limited to 30 A and, if clamped to an oscilloscope, it would be seen to be capped at 30 A and
never achieve the target of 40 A.
Another case is when working with a function which is applied to the input voltage. If here the static voltage is
set higher than the amplitude plus offset then at function start there will be no reaction, as the voltage regulation
limits down to 0 with an electronic load, other than current or power. The correct settings for each of the other set
values is therefore essential.