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EPS Stromversorgung GmbH
Alter Postweg 101 • 86159 Augsburg
Germany
Fon: +49 821 / 570451-0
Fax: +49 821 / 570451-25
www.eps-germany.de
PSI 10000 4U Serie
Visualisation:
Without interpolation - the curve results in steps
With interpolation - the curve remains linear
An example: the dwell time of the 3450
th
curve point is defined as 3 minutes, which is 180 seconds. There will be
180 / 0.5 -1 = 359 intermediate steps calculated and set until reaching the 3451
st
point. In mode DAY U/I the MPP
voltage changes from 75 V to 80 V and the MPP current changes from 18 A to 19 A. When calculated, this would
mean a ΔU/Δt of 27.7 mV/s and a ΔI/Δt of 5.5 mA/s. Depending on the device in use, such small steps in voltage
or current may not be doable. However, the device would try to set the first intermediate step with 75.0138 V and
18.0027 A.
3.10.15.7 Data recording
There is the option to record data during the simulation run, in any mode. The data can be stored to USB stick once
the simulation is finished or read via digital interface, which even allows for reading the data while the simulation
is still running.
As long as the simulation is running, the device will record one data set every 100 ms into an internal buffer. This
interval isn’t adjustable. The max. number of data sets, here also called indexes, is 576,000. This results in a
max. record time of 16 hours. The indexes are internally counted with every new record. When reaching the max.
number, the index will restart from 1, overwriting former data. Every index will contain 6 values.
When configuring the PV simulation, the recording feature is locked at first (button greyed out). Only when stopping
the simulation and leaving the control screen back to the configuration, the button becomes accessible. It then
allows to store a CSV with a specific number of rows. This number depends on the current index counter. Contrary
to remote control where it’s possible to address every index of the max. 576,000 the save to USB feature will always
store all indexes between 1 and the counter. Every next simulation run also resets the counter.
CSV file format when saving the recorded data to USB stick (in the example all values are with unit):
Index
= Ascending number
Uactual
= Actual voltage on the DC output
Iactual
= Actual current on the DC output
Pactual
= Actual power on the DC output
Umpp / Impp / Pmpp
= Voltage, current and power in the
MPP of the currently calculated PV curve
The global parameter “USB logging with units (V,A,W)” in the General Settings of the device
MENU selects whether the values in the CSV file are with or without physical unit. Default is
with unit. Another parameter, “USB decimal point format” selects whether the device saves the
CSV with comma (US) or semicolon (Standard) and defines the decimal point (dot and comma).
The example CSV above shows the european format with decimal comma.
