Sungrow SG250HX-US, Руководство пользователя

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AC circuit breaker
Over-current protection devices, such as AC circuit breakers and fuses, must be
installed on the AC side of the inverter and the grid side to ensure safe disconnec-
tion between the inverter and the grid..
• Do not connect any local load between the inverter and the AC circuit breaker
except for the tracking axis.
• Multiple inverters cannot share one AC circuit breaker.
table 5-4 Recommended specifications of AC circuit breaker
Recommended rated
voltage
Recommended rated current
800V 250A
Requirements for multiple inverters in parallel connection
A maximum of 15 inverters can be connected in parallel to a winding of a box-type trans-
former when multiple inverters are connected to the grid in parallel. Please contact SUN-
GORW to confirm the technical solution if otherwise required.
MV transformer
The MV transformer used together with the inverter should meet the following requirements:
• The transformer may be a distribution transformer, and it must be designed for the typical
cyclical loads of a PV system (load in the day and no load at night).
• The transformer may be of the liquid-immersed type or dry type, and shield winding is
not necessary.
• The line-to-line voltage on the LV side of the transformer should endure the AC side out-
put voltage of the inverter. When the transformer is connected to to the IT grid, to-ground
withstanding voltage of the LV winding of the boosting transformer, the AC cables, and
the secondary equipment (including the relay protection device, detection & measuring
device, and other related auxiliary devices) should not be lower than 1500Vdc.
• Two double split windings in the same phase of the transformer should be able to endure
a system voltage of no less than 1500Vdc.
• The line-to-line voltage on the HV side of transformer should comply with local grid
voltage.
• A transformer with a tap changer on the HV side is recommended in order to keep the
voltage consistent with the grid voltage.
• The running capacity of the transformer must meet the inverter’s output requirements. At
an ambient temperature of 30
℃ , the transformer should be able to run for long when the
load is 1.1 times the rated load.
• When the transformer capacity is 3.15MVA, it is recommended to use a transformer with
a short-circuit impedance of 7% (permissible tolerance: ±10%).
User Manual 5 Electrical Connection