User`s manual

Operation
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users manual inverter SE2.8i - SE3.8i - SE4i - SE5i
3.1 Overview
The SE inverter will operate automatically. Once the insolation is strong enough to generate DC input voltage over the pre-set threshold value,
the inverter turns itself on. The inverter feeds power into the grid after input voltage over the PV start voltage and all necessary conditions
are checked and fulfilled. The inverter goes into Monitoring mode from the Grid/MPP mode if the DC input voltage is under the minimum MPP
voltage. Once the DC input voltage falls below the pre-set threshold value, the inverter will shut down itself. There are five main operating
modes described in detail below.
System Check: When the DC input voltage goes above the PV start voltage, the inverter is powered-up and initial, and then enters the System
Check mode. In this operating mode, the inverter runs diagnostics. This stage takes only a few seconds.
Monitoring: After System Check is complete the inverter enters the Monitoring mode. In this operating mode, the inverter monitors all parameters
on both AC and DC sides in order to insure that connecting to the mains is safe. All conditions must be fulfilled and last for a certain period of
time, then the system will enter the Grid/MPP mode.
Grid/MPP: After the Monitoring mode, the SE inverter confirms that all conditions necessary for feeding the power into the utility grid are fulfilled.
The inverter will turn on the AC relays and start feeding the AC power to the grid. In this operating mode, the inverter continues to convert
the DC power generated by the PV array to the AC power that is then fed into the grid.
Fault: When fault(s) occurs and have been detected in the operating mode described above, the inverter will terminate the present state, stop
feeding power to the grid, and then jump into the Fault mode that executes a preset sequence. When the faults have been cleared for certain
period of time, the inverter will leave Fault mode and enter System Check mode. Some faults, like component failure, will cause the inverter
go into the Idle mode that will need service staff to clear the error(s).
Idle: Once the inverter jumps into this operating mode, the inverter has detected a malfunction of the ENS and has stopped feeding the power