Electrical Connection; Requirements For The Electrical Connection; Permitted Grid Configurations; Residual-Current Monitoring Unit - SMA Sunny Tripower X 12 Operating Manual

6 Electrical Connection

6 Electrical Connection
6.1

Requirements for the electrical connection

6.1.1

Permitted grid configurations

The inverter approved for operation in the following utility grids:
• TN-C
• TN-S
• TN-C-S
1)
• TT
Operation of the inverter in IT or Delta IT grids is not permitted.
Figure 8: Overview of approved grid configurations
6.1.2

Residual-current monitoring unit

The inverter does not require an external residual-current device when operating. If local
regulations require the use of a residual-current device, the following must be observed:
1)
It must be ensured that the local grounding has a sufficiently low-impedance connection to the
grounding of the transformer, otherwise operational leakage currents can lead to potential differences.
For error-free operation, the ground potential at the neutral point of the transformer must be the same as
that of the grounding conductor connection on the inverter. SMA Solar Technology AG recommends a
bridge between N and grounding conductor at the point of interconnection to ensure error-free
operation. Improper implementation of the transformer/grid connection with regard to low-impedance
grounding/zeroing of the neutral point can lead to a device defect that is not covered by the warranty.
36 STPxx-50-BE-en-11
SMA Solar Technology AG
Operating manual