SMA SC 400HE Installation - Manual (Page 37)

SMA Solar Technology AG Internal Electrical Connections
Installation Guide SCxxxHE-IEN104432 37
5 Internal Electrical Connections
Once both switch cabinet units have been installed alongside each other and are mechanically
connected, the individual cabinets must be electrically joined together.
For internal electrical connection of the two cabinets, the following connections must be established:
• Power cable connection between the sinusoidal filter and power unit
• Grounding connection between AC cabinet and DC / inverter cabinet
• Control cables on the transfer terminal strip
• Communication between the Sunny Central Control and the power unit in the inverter cabinet
• Communication between the Sunny Central Control and the insulation monitoring system
5.1 Connecting the Power Cable Connection
The power cable connection of the power units in the inverter cabinet to the sinusoidal filter choke in
the AC cabinet is to be carried out using the delivered Radox cables (W131 to W139).
According to the circuit diagram included in the delivery, one power unit per phase is connected to
the sinusoidal filter choke, each measuring 3 x 1 x 185 mm². The corresponding terminal screws are
located on the connection points.
Realizing the electrical connection
The circuit diagram provided must be used for establishing the electrical connections and
connectors.
To prepare the inverter for the external AC and DC connections, all internal connections
must be installed first.
Installing the internal connections
For the most part, the internal connections are pre-assembled and must be plugged or
screwed in when joining the cabinets together.
Observe the cable length
The Radox cables included in the delivery have different lengths for left-hand and right-
hand systems. Arrange the cables according to the circuit diagram of the respective Sunny
Central.