SMA Solar Technology AG
15. If a multifunction relay is used, reconnect the supply voltage to the load.
☑ All 3 LEDs start to glow and the start-up phase begins. The start-up phase may take
several minutes.
☑ The green LED is glowing. If applicable, the display alternates between the firmware
version, the serial number of the inverter, the NetID, the configured country data set and
the display language.
16. Perform the respective measures indicated when the following LED status appears:
LED status
Green LED is
flashing
The red LED is
glowing and an
error and event
message appear
in the display.
17. After replacing the assembly, check the correct functioning of the SELV circuit. Activate the fan
test for this purpose:
• To check the correct functioning of the SELV circuit, perform a fan test:
– Call up the user interface of the communication product or software and log in as
Installer or User.
– Select the parameters Device > Cooling system > Fan test. If the fan starts, the
SELV circuit is fault-free. If the fan does not start, contact Service.
• To check the fault-less functioning of the SELV circuits, check the functioning of
communication (see inverter manual).
18. Ensure that the inverter feeds in correctly.
19. Perform the VAC test (see Section 9, page 31).
9
Performing the VAC Test
Due to the replacement of the assembly, elements in the supply voltage measurement area were
replaced. To ensure that the supply voltage measurement in the inverter has the required accuracy,
the installer must carry out a VAC test.
The VAC test compares the AC voltage present in the utility grid with the AC voltage measured by
the inverter. The inverter may display up to 5 V more or 1 V less than the applied AC voltage.
Requirements:
☐ A measuring device suitable for the VAC measurement must be available.
☐ During measurement, devices causing fluctuations in the utility grid (e.g. other inverters) must
be switched off or set to Stop.
Replacement Manual
Cause
The DC input voltage may still be
too low or the inverter is monitoring
the utility grid.
The inverter has detected an error.
Measures
Wait that the DC input voltage is suf-
ficiently high and the grid-connec-
tion conditions are met. Then the in-
verter will start operation automati-
cally.
Eliminate the error (see the inverter
manual).
STP8-17-STP15-20TLEE-AC-CON-RM-xx-10
9 Performing the VAC Test
31