5 Planning the installation
Installation and Operation Manual for RPI M50A
26
5.8 DC connection
NOTICE
Machine and equipment damage may occur.
Exceeding the maximum current per DC input can cause an overheating of the DC inputs.
► Always consider the maximum current of the DC inputs when planning the installation.
5.8.1 Symmetrical and asymmetrical power input
The inverter operates using two separate MPP trackers that can handle both symmetrical and asymmetrical
power input. This allows you to set up complex PV system designs. For example: east/west-facing roof (asym-
metric load) or a south facing roof such as a dormer (asymmetrical load).
8:00 13:00 18:00
kW
Total
East Roof
West Roof
East West
Fig. 5.13: Concept of 2-MPP-tracker system for asymmetrical power input
The following gures explain how symmetrical and asymmetrical power input is handled:
Symmetrical power input Asymmetrical power input
I
max
U
max
U
startup
Input Current
Input Voltage
Max. Power MPPT Range
Input Current DC 1 Input Current DC 2
I
max
U
max
U
startup
Input Current
Input Voltage
Max. Power MPPT Range
Input Current DC 1 Input Current DC 2
Fig. 5.14: I-U curve for symmetrical and asymmetrical power input (schematic diagrams)