5 Installation
SMA Solar Technology AG
28
STPS60-IA-xx-13
Installation Manual
5.7 Overview of the connection area
Figure 19: Overview of the connection area
5.8 AC Grid Connection
The inverter may only be connected to a three-phase utility
grid.
IMI detection:
The inverter has a built-in IMI/RCMU (Insulation Monitoring
Interrupter / Residual Current Monitoring Unit).
The inverter acts on residual DC current and a sudden
change in the ground fault current. This functionality is
activated during normal operation.
Insulation resistance detection:
The inverter has a built-in insulation resistance detection. The
insulation resistance detector performs a measurement of
the connected battery resistance to ground before the
inverter connects to the utility grid. If the resistance is below
the grid code set value, the inverter will wait and re-measure
the resistance after a short while. If the resistance is above
the grid code setpoint, the inverter performs a self-test and
connects to the utility grid.
Grounding:
The inverter is not equipped with a transformer and is
intended to be installed with an ungrounded battery (with
floating potentials).
B
C
D
E
F
G
H
A
PELV (safe to touch)
B
Device grounding
G
Ethernet interface x 2
H
RS485 interface (not in use)
Live parts
A
AC terminals
E
DC terminals
Miscellaneous
C
AC overvoltage protection (SPDs)
D
DC overvoltage protection (SPDs)
F
DC load-break switch
