Install Manual

Table Of Contents
6 Electrical Connection
SMA Solar Technology AG
Installation Manual STP33-62-US-41-IA-en_es-11 27
Load-break switch an cable protection:
In PV systems with multiple inverters, protect each inverter with its own overcurrent protective
device. Observe the maximum permissible fuse protection (see Section10 "Technical Data",
page58). This will prevent residual voltage from being present at the corresponding
conductor after disconnection.
The load-break switch or circuit breaker must be listed (see National Electrical Code
®
ANSI/
NFPA 70).
Loads installed between the inverter and the overcurrent protective device must be fused
separately.
The overcurrent protective device for the AC output circuit is to be provided by others.
The inverter is equipped with an AC switch in accordance with UL508 which can be used as
a service switch.
Compatible grid configuration:
The inverter is approved for connection to a utility grid with 277/480V wye connection.
6.2.2 Connecting the Inverter to the Utility Grid
Requirements:
All electrical installations must be carried out in accordance with the applicable electrical
standards on site and the National Electrical Code
®
ANSI/NFPA 70.
The AC and DC electric circuits are isolated from the enclosure. If required by the National
Electrical Code
®
, ANSI/NFPA 70, the installer is responsible for grounding the system.
The connection requirements of the grid operator must be met.
The grid voltage must be within the permissible range. The exact operating range of the
inverter is specified in the operating parameters.
Procedure:
1. Disconnect the circuit breaker from all three line conductors and secure against reconnection.
2. Ensure that the AC load-break switch and the DC load-break switch are in the O position and
are secured against reconnection.
3. If the enclosure lid of the AC-Connection Unit is
mounted, remove all ten screws of the enclosure lid
(TX25) and remove the enclosure lid towards the
front.
10x
4. Remove the adhesive tape from the enclosure opening for the AC connection.
5. Insert the conduit fitting into the opening and tighten from the inside using the counter nut.
6. Attach the conduit to the conduit fitting.
7. Guide the conductors from the conduit into the AC-Connection Unit.
ENGLISH