SMA PVO-N-20 - Manual (Page 25)

SMA Solar Technology AG 7 Electrical Connection
Installation Manual PVO-BOX-IA-en-10 25
7.2 AC Connection
7.2.1 Conditions for AC Connection
Cable Requirements:
☐ When using a fault indication relay: the AC cable must have at least 4 wires for the phase (L),
the neutral conductor (N), the functional earth (FE) and the fault indication relay. In most
countries, the green-yellow conductor for protective earth (PE) must not be used for functional
earthing.
☐ When not using a fault indication relay: the AC cable must have at least 3 wires for L, N and
FE. In most countries, the green-yellow conductor for protective earth (PE) must not be used for
functional earthing.
☐ All cables must be double-insulated.
☐ External diameter: 5 mm - 13 mm.
☐ Conductor cross-section: 0.5 mm
2
- 1.5 mm
2
.
Miniature Circuit-Breaker
Inverter Earthing
Danger to life due to fire.
If a generator (inverter) and a load (SMA PV Offset Box) are connected to the same miniature
circuit-breaker, the protective function of the miniature circuit-breaker is no longer guaranteed. The
currents from the inverter and the electricity grid can accumulate to overcurrents which are not
detected by the miniature circuit-breaker.
• Fuse the SMA PV Offset Box with a separate miniature circuit-breaker. Tip: you can connect
up to 50 SMA PV Offset Boxes to the same miniature circuit-breaker.
• Observe the maximum permissible fuse protection of the SMA PV Offset Box when selecting
the miniature circuit-breaker (see Section 12 "Technical Data", page 49).
Danger to life due to electric shock
If the SMA PV Offset Box is operated with an inverter with AC connector and the AC connector is
disconnected during operation of the SMA PV Offset Box, the inverter enclosure will be live.
• Connect a second, non-disconnectable protective conductor to the inverter.
• Do not pull the AC connector out during operation with an SMA PV Offset Box.