SMA AUTOMATIC SWITCH BOX M-20 - Manual (Page 38)

5 Electrical Connection SMA Solar Technology AG
38 AS-BOX-M_L-IA-IEN110320 Installation Guide
5.8 Connecting the Consumption Meter
Connection terminals:
Risk of lethal electric shock.
The residual current devices between the power distribution grid and the Automatic Switch Box
would lose its protective function due to the Backup system. Since the Backup system makes the
tripping of the residual current device ineffective.
• Do not install a residual current device between the power distribution grid and the
Automatic Switch Box.
Risk of electric shock due to connected neutral conductor when connecting in a TN
system.
The Backup system requires a grounded neutral conductor in order to form a TN grid in case of a
grid failure and be able to apply the appropriate protective measures.
• Do not install any switching elements in the grounded neutral conductor to the
Automatic Switch Box.
Risk of electric shock due to incorrect grounding of the PEN conductor on the grid side in
case of a connection to a TN system.
• Ground the PEN conductor on the grid side within the house connection box (e.g. when the
house connection box is linked to the equipotential bonding bar).
Destruction of the Automatic Switch Box due to missing back-up fuse.
To limit a possible short-circuit current from the power distribution grid and to secure the cables in
the Automatic Switch Box, a fuse between the consumption meter and the Automatic Switch Box is
necessary.
• Insert a back-up fuse into the distribution. Take the nominal current, the short-circuit switching
capacities and the maximum cut-off current into account (see section 10 ”Technical
Data”, page 53).
Displayed graphic
As an example, only the Automatic Switch Box L will be graphically displayed in this section.
The labeling of the connection terminals as well as the procedure for connecting the
Automatic Switch Box M is identical.