User manual

Page 71
EA Elektro-Automatik GmbH
Helmholtzstr. 31-33 • 41747 Viersen
Germany
Fon: +49 2162 / 3785-0
Fax: +49 2162 / 16230
www.elektroautomatik.de
[e-mail]
PSI 9000 2U Series
► How to save a sequence table (100 sequences) to a USB ash drive:
1. Do not plug the USB ash drive yet or remove it.
2. Access the function selection menu of the function generator via MENU -> Function Generator -> Arbitrary
3. Tap on , then . The device will request you to plug the USB ash drive now.
4. After plugging it, the device will try to access the ash drive and nd the folder HMI_FILES and read the
content. If there are already WAVE_U or WAVE_I les present, they will be listed and you can either select
one for overwriting with , otherwise select for a new le.
5. Finally save the sequence table with .
3.9.11 Ramp Function
The following parameters can be congured for a ramp function.
Value Range Description
Ustart / Istart 0...Nominal value of U, I Start value (U,I)
Uend / Iend 0...Nominal value of U, I End value (U, I)
t1 0,1 ms...36000 s Time before ramp-up or ramp-down of the signal.
t2 0.1 ms...36000 s Ramp-up or ramp-down time
Schematic diagram: Application and result:
A.start
t
A
t1 t2
A.End
This function generates a rising or falling ramp between start
and end values over the time t2. Time t1 creates a delay before
the ramp starts.
The function runs once and stops at the end value.
Important to consider are the static values of U and I which dene
the start levels at the beginning of the ramp. It is recommended
that these values are set equal to those in A.start, unless the load
at the DC output should not be provided with voltage before the
start of the ramp. In that case the static values should be set to
zero.
10h after reaching the ramp end, the function
will stop automatically (i.e. I = 0 A, in case the
ramp was assigned to the current), unless it
has been stopped manually before.
3.9.12 UI and IU table functions (XY table)
The UI and IU functions offer the user the possibility to set a DC output current dependant on the DC output volt-
age, or a DC output voltage dependant on the DC output current. The function is table driven with exactly 4096
values, which are distributed over the whole measured range of actual output voltage or output current in the range
of 0...125% Unom or Inom. The table can either be uploaded from a USB ash drive through the front side USB
port of the device or via remote control (ModBus protocol or SCPI). The functions are:
UI function: U = f(I)
IU function: I = f(U)
In the UI function, the equipment measuring circuit determines the level from 0 to maximum of the output current.
For each of the 4096 possible values for output current a voltage value is maintained by the user in the UI table
which can be any value between 0 and nominal value. The values uploaded from a USB ash drive will always
be interpreted as voltage values even if the user calculated them as current values and incorrectly loaded them
as a UI table. The UI function suits very good for the simulation of fuel cell characteristics.