Minimum frequency – SMA SB 1200 Installation User Manual
Page 44
Commissioning
SMA Solar Technology AG
44
SB12-17-IA-en-52
Installation Guide
Minimum Frequency
In the last step, the inverter tests the minimum frequency.
During the test sequence, the frequency limit applied is
shown in the display of the inverter.
The frequency limit is increased successively until the shut-
down threshold is achieved and the inverter disconnects
from the grid.
Once the inverter has disconnected from the grid, the display successively shows the following values
one after the other:
• Disconnection value,
• Calibration value,
• Reaction time,
• Present grid frequency.
When the inverter has carried out the 4 tests, it switches to MPP operation mode ("MPP"). The original
calibration values are then re-set and the inverter automatically connects to the grid. If you would like
to carry out the test again, you have to disconnect the inverter, in other words you have to disconnect
it on the AC and DC sides and then later re-activate it. You can then restart the self-test as described
in the following section 6.3.1 ”Starting the Self-Test by Tapping” (page 40). The inverter begins the
test sequence again, as described in section 6.3.2 ”Completion of the Self-Test” (page 40).