Elektro-Automatik PSI 9000 DT Series, Руководство по эксплуатации

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EA Elektro-Automatik GmbH
Helmholtzstr. 31-37 • 41747 Viersen
Germany
Fon: +49 2162 / 3785-0
Fax: +49 2162 / 16230
www.elektroautomatik.de
ea1974@elektroautomatik.de
PSI 9000 DT Series
3.10.2.4 Minimum slope / maximum ramp time
When using a rising or falling DC offset, i. e. start offset doesn’t equal end offset, with functions like ramp, trap -
ezoid, triangle or even sine wave, it requires a minimum slope or else the adjusted settings would be neglected
by the device. Calculating the minimum slope can help to determine if a certain ramp over time can be achieved
by the device or not. Example: model PSI 9080-60 DT is going to be used, with 80 V and 60 A rating. Formula:
minimum slope = 0.000725 * rated value / s . For the example model it results in ΔU/Δt of 58 mV/s and ΔI/Δt of
ca. 44 mA/s. The maximum time which can be achieved with the minimum slope then calculates as approximately
1379 seconds according to formula t
Max
= rated value / min. slope.
3.10.3 Method of operation
In order to understand how the function generator works and how the value settings interact, the following should
be noted:
The device operates, including in function generator mode,always with the three set values U,I and P.
The selected function can be used on one of both the values U or I, the other two are then constants and have
a limiting effect. That means if, for example, a voltage of 10 V is set for the DC output, a load is connected and
a sine wave function should operate on the current with an amplitude of 20 A and offset 20 A, then the function
generator will create a sine wave progression of current between 0 A (min) and 40 A (max), which will result in an
output power between 0 W (min) and 400 W (max).The output power, however, is limited to its set value. If this
was 300 W then, in this case, the current would be limited to 30 A and, if clamped to an oscilloscope, it could be
seen as truncated at 30 A and never reach the target of 40 A.
3.10.4 Manual operation
3.10.4.1 Function selection and control
Via the touch screen all of the functions described in 3.10.1 can be selected,
configured and controlled. This only available while the DC output is switched
off.
► How to select a function and adjust parameters
1.
While the DC output is switched off, tap touch area on
the main screen.
2.
In the menu overview tap on the touch area and then on the desired function. The function selec-
tion screen (see figure above) will appear. Note: this touch area is locked in “R mode” (adjustable resistance).
3.
Depending on the choice of function you would then be requested to select to which physical quantity the
function is going to be applied:
or .
4.
Adjust all necessary parameters.
Mind the minimum slope when setting up functions with ramps or, when using the arbitrary
function, if the offset changes between start and end of a sequence point. See 3.10.2.4.
5.
Do not forget to adjust the overall limits of voltage, current and power, which you can access with touch
area .
When entering function generator mode, those limits are reset to safe values, which can
prevent the function from working at all. For example, if you apply the selected function
to the output current, then the overall current limit should not interfere and should at least
be as high as amplitude.