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Identification: MD-AL-GI-00
Rev. 1.1 of 15/03/2021 - Application: GID
User’s Manual 3PH 50000TL-60000TL-V1
Rev. 1.1 15/03/2021
E. Monitoring input strings
The inverter monitors and displays the input voltage and current of each string. It also controls the status of
the strings and generates an alarm in case of error (shown on the display).
E. Overvoltage arrester monitoring (only for S4 and S5 versions)
The inverter monitors the status of the surge arresters (both AC and DC), and in the event of a fault
generates an alarm in the error list (visible from the display).
2.3.
Module protection
A.
Anti-islanding
The inverter is equipped with a protection system which automatically shuts down the system during power
outages. This is called an “anti-islanding” system. This protects electrical workers when they are trying to
repair lines on the grid, in compliance with the applicable national laws and regulations.
B. RCMU
The inverters are equipped with a redundancy on the reading of the ground leakage current, on both the
direct and alternating current sides. The ground leakage current is measured simultaneously and
independently by two different processors: it is sufficient for one of the two to detect a fault in order to
trigger the protection, resulting in separation from the grid and shutdown of the operation.
C. Grid monitoring
Continuous monitoring of the grid voltage to ensure that the voltage and frequency values stay within the
operating limits.
D. Internal protection of the inverter device
The inverter has all kinds of internal protections to protect the device and internal components when
abnormal situations occur on the grid or DC input line.
E. Ground fault protection
The inverter must be used with photovoltaic modules connected with “floating” connections, i.e. with
positive and negative terminals that are not grounded. An advanced ground fault protection circuit
continuously monitors the ground connection and disconnects the inverter when a ground fault is detected.
The ground fault condition is indicated by a red LED on the front panel.
