Load-Break Switch And Cable Protection; Additional Grounding - SMA Sunny Tripower X 12 Operating Manual

SMA Solar Technology AG
☐ The inverter is compatible with residual-current devices of type A and B that have a rated
residual current of 100 mA or higher. Each inverter in the system must be connected to the
utility grid via a separate residual-current device.
6.1.3

Load-break switch and cable protection

Damage to the inverter due to the use of screw-type fuses as load-break
switches
Screw-type fuses (e.g. DIAZED fuse or NEOZED fuse) are not load-break switches.
• Do not use screw-type fuses as load-break switches.
• Use a load-break switch or circuit breaker as a load disconnection unit (for information and
design examples, see the Technical Information "Miniature circuit breaker" at www.SMA-
Solar.com).
☐ In PV systems with multiple inverters, protect each inverter with a separate three-phase circuit
breaker. Make sure to observe the maximum permissible fuse protection (see Section 14,
page 101). This will prevent residual voltage from being present at the corresponding cable
after disconnection.
☐ Loads installed between the inverter and the circuit breaker must be fused separately.
6.1.4

Additional grounding

Safety in accordance with IEC 62109
The inverter is not equipped with a grounding conductor monitoring device. In order to
guarantee safety in accordance with IEC 62109, you must take one of the following
measures:
• Connect a grounding conductor made of copper wire with a cross-section of at least
10 mm² to the terminal block for the AC cable.
• Connect additional grounding with the same cross-section as the connected grounding
conductor to the terminal block for the AC cable (see Section 6.5, page 44). This
prevents touch current if the grounding conductor at the terminal block for the AC cable
fails.
Connection of an additional grounding conductor
In some countries, an additional grounding conductor is generally required. In each case,
observe the locally applicable regulations.
• If additional grounding is required, connect an additional grounding that has at least the
same cross-section as the connected grounding conductor to the terminal block for the AC
cable Connecting Additional Grounding(see Section 6.5, page 44). This prevents touch
current if the grounding conductor at the terminal block for the AC cable fails.
Operating manual
NOTICE
6 Electrical Connection
STPxx-50-BE-en-11 37