Inverter vision max (3-phase supply)

    General Planning Guidelines

    These notes apply generally to all of the following application examples for the Inverter vision max.

    Sizing Guidelines for Inputs and Outputs on the Inverter vision max

    On the Inverter vision max, the connector for the grid connection is suitable for conductor cross sections up to 16 mm², while the connector for the backup connection can accommodate conductor cross sections up to a maximum of 10 mm².

    Using 5x16 mm² and 5x10 mm² or 5x6 mm² as examples, and taking into account the permissible voltage drop for PV generators [1%] and loads [3%, calculated here proportionally at 2%], the following cable lengths can be implemented:

    Overview for Generators—Grid Connection Plugs for 1% Voltage Drop

    Power Class
    Inverter [kW]    		Length [m] for
    Conductor cross section 10 mm²    		Length [m] for
    Conductor cross section 16 mm²

    30

    Not suitable

    18

    25

    Not suitable

    18

    20

    14

    21

    15

    19

    28

    Overview for Consumers - Backup Connection, Proportional 2% Voltage Drop

    Power Class
    Inverter [kW]    		Length [m] for
    Conductor cross section 6 mm²    		Length [m] for
    Conductor cross section 10 mm²

    30

    Not suitable

    28

    25

    20

    34

    20

    25

    42

    15

    33

    57

    Overview of Maximum Currents per Phase for Proper Wire and Fuse Selection

    Power Class
    Inverter [kW]    		Max. Current per Phase [A] Grid Connection PowerMax. Current per Phase [A] Consumer Backup Connection

    30

    53

    45.5

    25

    53

    37.9

    20

    45.5

    30.3

    15

    34.1

    22.7

    Depending on the power class, cable cross-section, and installation method, circuit breakers in the sizes C 40 A, C 50 A, and C 63 A are used.

    The selection of the correct circuit and the appropriate circuit breaker must be made with due consideration of the specific conditions.

    Residual Current Circuit Breaker (RCD) at the Grid Output

    Installing a fault current circuit breaker upstream of the inverter is optional and depends primarily on country-specific regulations or local requirements (e.g., specific fire safety regulations) governing the use of fault current circuit breakers.
    If a fault current circuit breaker is installed, the breaker must have a rated residual current of at least 300 mA.

    Residual Current Circuit Breaker (RCD) at the backup output

    For backup power operation, an additional external residual current circuit breaker must be installed at the backup output to ensure that residual current protection requirements are met even during off-grid operation.

    InverterCentral RCD at the backup output
    Inverter vision oneType A, ≥ 100 mA
    Inverter vision threeType A, ≥ 300 mA
    Inverter vision maxType A, ≥ 300 mA

    Existing 30-mA RCDs in the final circuits must continue to be installed in accordance with national installation regulations.

    RCD Selection: Type A or Type A S

    Depending on the system configuration, either a Type A RCD or a selective Type A S RCD can be used for the central RCD at the backup output. This selection affects the tripping behavior in the event of faults in the downstream final circuits.

    The linked selection guide explains the differences between Type A and Type A S, the requirements for using a selective RCD, and the necessary verification of the tripping conditions. The goal is to achieve the most selective tripping possible so that, in the event of a fault, only the affected final circuit—and not the entire backup supply—is shut down whenever possible.

    Selection Guide: RCD Type A or Type A S (196.8 KB,  PDF)
    Print