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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
EL 9000 B 15U/24U Series
3.10.14.2 Mode MPP2
This mode tracks the MPP, so it is closest to the operation of
a solar inverter. Once the MPP is found, the function won’t
stop, but try to track the MPP permanently. Due to the nature
of solar panels this can only be done below the level of the
MPP. As soon as this point is reached, the voltage starts to
sink further and so does the actual power. The additional
parameter
ΔP
defines how much the power may sink before
the direction is reversed and the voltage starts to rise again
until the load reaches the MPP. The result are zigzag shaped
curves of both, voltage and current.
A typical curve display is shown in the picture to the right.
For the example, the
ΔP
was set to a quite small value, so
the power curve looks almost linear. With a small
ΔP
the
load would always track close to the MPP.
Following parameters can be configured for tracking mode
MPP2
:
Value Range
Description
U
OC
0...Nominal value of U Voltage of the solar panel when unloaded, taken from the panel specs
I
SC
0...Nominal value of I Short-circuit current, max. specified current of the solar panel
Δt
5 ms...65535 ms
Interval for measuring U and I during the process of finding the MPP
ΔP
0 W...0.5 P
Nom
Tracking/regulation tolerance below the MPP
3.10.14.3 Mode MPP3
Also called “fast track”, this mode is very similar to mode MPP2, but without the initial step which is used to find
the actual MPP, because mode MPP3 would directly jump to the power point defined by user input (U
MPP
, P
MPP
).
In case the MPP values of the equipment under test are known, this can save a lot of time in repetitive tests. The
rest of the function run is the same as with MPP2 mode. During and after the function, the least acquired MPP
values of voltage (U
MPP
), current (I
MPP
) and power (P
MPP
) are shown in the display.
Following parameters can be configured for tracking mode
MPP3
:
Value Range
Description
U
MPP
0...Nominal value of U Voltage in the MPP
I
SC
0...Nominal value of I Short-circuit current, max. specified current of the solar panel
P
MPP
0...Nominal value of P Power in the MPP
Δt
5 ms...65535 ms
Interval for measuring U and I during the process of finding the MPP
ΔP
0 W...0.5 P
Nom
Tracking/regulation tolerance below the MPP
3.10.14.4 Mode MPP4
This mode is different, because it does not track automatically. It rather offers the choice to define a user curve by
setting up to 100 points of voltage values, then track this curve, measure current and power and return the results
in up to 100 sets of acquired data. The curve points can be entered manually or loaded from USB stick. Start and
end point can be adjusted arbitrarily, Δt defines the time between two points and the function run can be repeated
up to 65535 times. Once the function stops at the end or by manual interrupt, the DC input is switched off and the
measured data is made available. After the function, the acquired set of data with the highest actual power will be
shown in the display as voltage (U
MPP
), current (I
MPP
) and power (P
MPP
) of the MPP. Going back on the screen with
RETURN then allows for data export to USB stick.
Following parameters can be configured for tracking mode
MPP4
:
Value
Range
Description
U
1
...U
100
0...Nominal value of U Voltage for the up to 100 user definable curve points
Start
1-100
Start point for the run of x out of 100 subsequent points
End
1-100
End point for the run of x out of 100 subsequent points
Δt
5 ms...65535 ms
Time before the next point
Rep.
0-65535
Number of repetitions for the run from Start to End
