EPS PSI 10000 4U, Руководство по эксплуатации

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PSI 10000 4U Serie
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 corresponding 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 offer 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, only 0...102% of that range are effective, because
set values are limited to max. 102% of the rating. It means that approx. 3277 values in that table are effective
while the rest is recommended to have the same value as in the highest effective entry at 100% or 102% voltage.
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 function’s definition is:
IU function: I = f(U)
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.
Uploading 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
graphically 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.