Sungrow SG2500U-MV, Системное руководство

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7 Commissioning System Manual
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may be damaged.
Make sure the environmental condition is stable since the voltage of PV array may change
with the solar radiation and the temperature of the PV cells. Use the U-I curve to record the
PV array situation. Commission the device when the PV array output situation is stable.
The PV field circuit fault (module fault or MV Station numbers deviation in
certain array), cable damages or connection looseness may cause the voltage
deviation exceeding 3% at stable environmental conditions.

Record the environmental parameters (temperature and radiation intensity, etc.).

Measure the resistance of cables (between the terminal box and the MV Station).

Record accurately all the measured data.
7.3.4 Checking Grid Voltage

Measure accurately the grid 3-phase line-to-line voltage: L1-L2, L1-L3, and L2-L3.
Measured data should not exceed the grid permissible voltage and the three phases
are in balance.
Adjust the transfer ratio of the transformer by qualified personnel if the grid
voltage deviation is serious.

Measure and record the grid frequency. Measured data should not exceed the grid
permissible frequency.

Measure the THD and check the curve if possible. The MV Station will stop running if
the THD is serious.

Record accurately all the measured data.
7.4 Preparation before Starting

Place the disassembled protection grills to their original positions and ensure the
connection is secure.

Close and lock the cabinet door.

Clean the device site. Make sure the position is clean without flammable or explosive
materials.

Ensure the ventilation of the installation place.

Recheck and ensure the switches upstream and downstream meet the requirements
and flexible enough.
7.5 Starting the Device
If all tests and measurements have been performed, and all measured values lie within the
acceptable range, the device can be switched on for the first time. Proceed as follows to
start the two modules inside the MV Station:
Step 1
Close the upstream and downstream switches of the MV Station.
Step 2 T
urn the “AUX SUPPLY” knob switch to the ON position.
Step 3 Manually close the auxiliary power supply switch inside the MV Station and wait the touch
screen to power on.