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Installation instructions Powador 3200 / 4400 / 5300 / 5500 / 6600_EN
4
Unit Description
C A U T I O N
Incorrect use is prohibited.
The transformerless Powador units are currently available in
nine different power ratings. The appropriate inverter type
is selected according to the maximum output of the installed
photovoltaic modules. The maximum output values can be
found in the data sheet (see Technical Data, section 3).
You can fi nd the name of your inverter on the name plate.
4.1 Scope of delivery
– Powador
– Wall bracket
– Installation kit
– Documentation
4.2 Dimensioning the PV generator
The selection of the PV generator is of central importance when
dimensioning a PV system. When doing so, you must ensure
that the PV array is also compatible with the inverter.
Observe the data provided in the data sheet (see section 3,
Technical Data) when dimensioning the PV array.
NOTICE
KACOCALC Pro, a dimensioning program for the easy
selection of PV modules, can be downloaded at no cost
at the following address http://www.kaco-newenergy.de
Dimensioning the PV generator:
The number of PV modules connected in series must be selected
in such a way that the output voltage of the PV generator stays
within the permitted input voltage range of the inverter – even
during extreme outside temperatures. In Central Europe, module
temperatures between -10 °C and +70 °C should be assumed.
Depending on the way in which the modules are installed and
the geographic location, +60 °C or +70 °C should be used when
calculating the voltage. The temperature coeffi cients of the solar
modules should be taken into account. The following criteria
must be met for calculating the voltage of the PV generator:
– V
0
(-10 °C) < max. input voltage (open circuit voltage, sec-
tion 4, Technical Data). Even at very low outside temperatures
(-10 °C), the open circuit voltage of the connected string must
lie within the permitted input voltage range. If the tempera-
ture falls from +25 °C to -10 °C, the open circuit voltage in
12 V modules increases by approx. 2.8 V per module (5.6 V for
a 24 V module). The open circuit voltage of the entire string
must be less than the open circuit voltage of the inverter.
– V
Mpp
(+60 °C) > min. input voltage (open circuit volt-
age, section 4, Technical Data). Even at very high module
temperatures (+60 °C), the MPP voltage of the connected
string should lie within the permitted input voltage range.
If the temperature increases from +25 °C to +60 °C, the
MPP voltage in 12 V modules decreases by approx. 3.6 V
per module (7.2 V for a 24 V module). The MPP voltage of
the entire string must then always be greater than the lower
MPP voltage of the inverter.
If the MPP voltage moves outside of the permitted input
range, the system still functions properly. In this situation, the
maximum possible amount of power is not fed into the grid,
but rather slightly less.
Provided that the input voltage is within the permitted input
voltage range, the inverter will not be damaged if a connected
PV generator provides current that is above the maximum
usable input current.
If the PV generator briefl y provides more than the inverter’s max.
PV generator power, especially with changing cloud cover and
relatively low module temperatures, the inverter may switch off
due to safety reasons and automatically switch on again after
a country-specifi c waiting period (see section 4, “Technical
Data”). The overload status is shown by a red LED and as plain
text on the display. Under normal circumstances, the dynamic
control of the inverter ensures that the inverter continues to
operate without interruption.
The PV array still represents the largest factor in the cost of a
PV system. For this reason, it is extremely important to obtain
maximum energy yields from the solar generator. To achieve
this, solar generators in central Europe should be oriented to
the south at a 30° angle of inclination. Positioning in the shade
should be avoided at all costs.
This orientation is quite often not possible due to structural
reasons. In order to achieve the same energy yield as an
optimally oriented PV array (south, 30° angle of inclination),
the PV array power can be increased.
For roofs with an east-west orientation, we recommend a PV
system with two separate strings. These two strings should
be assigned to the individual MPP inputs or inverters. The
output of the solar generator can be expected to be higher
in exposed areas in the mountains or in southern regions. For
this reason, an inverter with an output that is correspondingly
higher is required. Please consult with us or your specialty
dealer about this.
S e c t i o n 4 ·
U n i t D e s c r i p t i o n