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6. Functions
6.1 Description of Functions
Grid monitoring
Normal or fault state in the grid voltage is determined by a difference in voltage (Fault high
voltage and Fault low voltage) compared to a normal voltage. If the value is larger or smaller
than the pre-set value, the inverter is stopped. If the frequency in the grid voltage is deviated
from the pre-set value (line frequency) by more than fault high frequency and fault low
frequency, the inverter is not operated and stopped.
In order to start power generation at the normal grid state, the grid is operated after the
operation count-down (Line transfer. time) is elapsed. The frequency of the grid voltage can be
set according to the grid frequency.
MPPT control and total power generation
Since the output of the solar cell module varies depending on ambient temperature, humidity,
and sunlight, the MPPT (Maximum Power Point Tracking) algorithm should be run smoothly.
The method applied to the product is that the inverter is stopped when there is little current
pulsation and solar cell is reached up to PV stop voltage thereby unable to run the inverter
anymore.
The total power is accumulated and memorized so that total power can be checked.
Occurrence of fault state
When fault states that stop the inverter occur, related messages are displayed. After the cause
of fault state is removed, the system is re-run after some waiting time. If the same symptom
occurs again or the system is not re-run, please contact the main office.
Verification of fault state detail
The fault scan stores 50 faults from No. 0 to No. 49. The latest fault becomes No. 0.
The variables or fault state details in the past can be displayed using an UP and DOWN key in
the internal keypad of the inverter.
