© EA Elektro-Automatik in 2022, this information is subject to change without notice
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06230820_manual_psi_10000_3u_15kw_en_01
3.10.11
Ramp function
The following parameters can be configured for a ramp function.
Parameter
Range
Description
Start / End
0...Nominal value of U, I
Start and end value of the ramp
Time t1
0,1 ms...36,000,000 ms
Time before ramp-up or ramp-down
Time t2
0,1 ms...36,000,000 ms
Ramp-up or ramp-down time
Schematic diagram:
Application and result:
U
(I)
sta
rt
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 repeating
ramp, function Trapezoid would have to be used instead (see
3.10.8).
Important to consider are the static values of U or I which define the
start level before the ramp generation. It’s recommended that the cor-
responding static value is set equal to value
Start
, unless the load at the
DC output shall not be provided with a voltage before the actual start of
the ramp (time t1) . In that case the static value should be set to zero.
3.10.12
IU table function (XY table)
The IU function offers the user the possibility to set a DC output current dependent on the DC output voltage. The function is
table driven with exactly 4096 values, which are distributed over the whole measuring range of actual output voltage which
is 0...125% of the rated voltage. However, because of the upper limit of 102% of the rated current only the first 3342 values in
the XY table 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 (Mod-
Bus RTU protocol or SCPI). The function’s definition is:
IU function:
I = f(U) -> the device works in CC mode with a load working in CV mode
In the
IU function
, an internal measuring circuit measures the voltage on the DC output. 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 file naming.
Upload of a table from an USB stick must use text files 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 entries in the table are only checked for value and count. If all the values were to be graphical
-
ly plotted, a curve would be created which could include significant step changes in current or voltage.
That could lead to complications for connected load because the internal voltage measurement in the
power supply slightly fluctuates so that the current could jump backward and forward between two
entries in the table of which, in the worst case, one could have a value of 0 A and the other maximum
current.
