User Manual

Page 72
EA Elektro-Automatik GmbH
Helmholtzstr. 31-37 • 41747 Viersen
Germany
Fon: +49 2162 / 3785-0
Fax: +49 2162 / 16230
www.elektroautomatik.de
[e-mail]
PSB 9000 2.5 kW Series
Schematic diagram: Application and result:
U(I)start
t
U,I
t1 t2
U(I)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. To have a re-
peating ramp, function Trapezoid would have to be used instead
(see 3.11.8).
ImportanttoconsiderarethestaticvaluesofUandIwhichdene
the start levels at the beginning of the ramp. It’s recommended that
these values are set equal to those for Ustart/Istart, unless the load
at the DC terminal, when in source mode, shouldn’t be supplied
with voltage before the start of the ramp or, when in sink mode, the
external source shouldn’t be loaded with current yet. In that case
the static value should be set to zero.
3.11.12 IU table function (XY table)
TheIUfunctiono󰀨erstheuserthepossibilitytosetaDCcurrentdependantonthevoltagebeingpresentonthe
DC terminal. The function is table driven with exactly 4096 values, which are distributed over the whole measured
range of actual voltage in the range of 0...125% of the rated current. The table can either be uploaded from an USB
stickthroughthefrontsideUSBportorviaremotecontrol(ModBusprotocolorSCPI).Thefunctionisdenedas:
IU function: I = f(U)
Uploading of a table from an USB stick must use text les in CSV format (*.csv). Plausibility is
checked on loading (values not too high, number of values correct) and possible errors reported
in which case the table will not be loaded.
The 4096 values in the table are only checked for size and count. If all the values were to be
graphicallyplotted,acurvewouldbecreatedwhichcouldincludesignicantstepchangesin
current. That could lead to complications for the connected load or source if, for example, the
internal voltage measurement swings slightly so that the current jumps backwards and forward
between two values in the table, which, in the worst case, could be 0 A and the maximum
current.
3.11.12.1 Loading IU tables from USB drive
Theso-calledIUvaluetablescanbeloadedfromaleviaastandardUSB
stickthatisformattedasFAT32.Inordertoloadthele,ithastomeetfol-
lowingspecications:
• ThelenamealwaysbeginswithIU(notcase-sensitive)
• ThelemustbeatextleoftypeExcelCSV(semicolonasseparator)
and must only contain one column with exactly 4096 values without gaps
• Valueswithdecimalplacesmustusedecimalseparatorthatmatchestheselectioninthegeneralsetting“USBle
separatorformat”,whichalsodenesthedecimalseparatorbetweendotandcomma(USdefaultshouldbedot)
• No value may exceed the nominal value of the device. For example, if you have a 120 A model, none of the
4096 values may be higher than 120 A (the adjustment limits from the device’s front panel do not apply here)
• Thele(s)has/havetobeputinsideafoldernamedHMI_FILESintherootofthestick
Ifthesespecicationsarenotmet,thedevicewon’taccepttheleandputoutanerrormessageinthedisplay.
TheUSBdrivemaycontainmultipleIUleswithdi󰀨erentnamesandlistthemfortheselectionofone.