Manual

Table Of Contents

3.10.12 IU table function (XY table)

The IU function offer the user the possibility to set a DC input current dependent on the DC input voltage. The function is table

driven with exactly 4096 values, which are distributed over the whole measured range of actual input voltage in the range of

0...125% Unom, of which only 0...102% are effective . The table can either be uploaded from an USB stick through the front

side USB port of the device or via remote control (ModBus RTU protocol or SCPI). The functions are:

IU function: I = f(U)

In the IU function, an internal measuring circuit measures the voltage on the DC input. For every possible actual voltage on

the scale of 0...125% the loaded IU table holds a current value, which can be any value between 0 and rated current. The values

uploaded from an USB stick will always be interpreted as current values even if the user calculated them as voltage values

and loaded them as an IU table due to wrong le naming.

Uploading of a table from an USB stick must use text les in CSV format (*.csv). Plausibility is checked

when loading, i.e. values not too high, number of values correct etc. which may abort loading when errors

are found.

The 4096 values in the table are only checked for size and count. If all the values were to be graphically

plotted into a curve it could include huge step changes in the current. This could lead to complications

for the connected source if, for example, the internal voltage measurement swings slightly so that

the current jumps back and forth between a few values in the table which, in the worst case, could be

bounce between 0 A and the maximum current.

3.10.12 .1 Loading IU tables from USB stick

The so-called IU tables can be loaded from a le via a standard

USB stick that is formatted in FAT32. In order to load the le, it

has to meet following specications:

• The le name always begins with IU (not case-sensitive)

• The le must be a text le of type Excel CSV 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 Log le separator

format, which also denes the decimal separator between dot

and comma (US default should be dot)

• No value may exceed the rated current of the device model. For example, if you have a 420 A model, none of the 4096 values

must be higher than 420 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 path 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 stick

may contain multiple IU les with different names and list them for the selection of one.

► How to load an IU table from a USB stick:

1. While the DC input is switched off, open the function selection menu by tapping on , then select group XY table.

2. Insert the USB stick, if not already done, then tap on Import table and in the le selector coming up select the table you

want to load and conrm with . In case the le isn’t accepted for any of the above listed reasons, correct the

le format and content, then try again.

3. Tap to proceed to the next screen where you can adjust the global set values.

4. Finally proceed to the main function screen with , to start and control the function (also see

“3.10.4.1.

Function selection and control”).