Sungrow SG110CX-P2, Руководство пользователя

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Inverter Recommended residual current
SG125CX-P2 1250 mA
SG110CX-P2 1100 mA
Multiple Inverters in Parallel Connection
If multiple inverters are connected in parallel to the grid, ensure that the total number of par-
allel inverters does not exceed 25.
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 output volt-
age of inverter. When the transformer is connected to the IT grid, to-ground withstanding
voltage of the LV winding of the transformer, the LV side AC cables, and the LV side sec-
ondary equipment (including the relay protection device, detection & measuring device,
and other related auxiliary devices) should not be lower than 1,100V.
• The line-to-line voltage on the HV side of the transformer should comply with the local
power grid voltage.
• A transformer with a tap changer on the HV side is recommended in order to keep con-
sistent with the grid voltage.
• The voltage drop of system cable is no more than 3%.
• The DC component that the transformer can withstand is 1% of the fundamental current
at rated power.
• For thermal rating, the load curve of the transformer and environment conditions should
be taken into account.
• The apparent power of the inverter should never exceed the power of the transformer.
The maximum AC current of all inverters connected in parallel must be taken into ac-
count. It is recommended that the total number of inverters that are connected to the grid
not exceed 25.
• The transformer must be protected against overloading and short circuit.
• The transformer is an important part of grid-connected PV generation system. The fault
tolerance capacity of the transformer should be taken into account at all times. The fault
include: system short circuit, grounding fault, voltage drop, etc.
• Take ambient temperature, relative humidity, altitude, air quality, and other environmental
conditions into account when selecting and installing the transformer.
• When the anti-PID function is enabled, observe the following items:
– If the LV side winding is in Y shape, neutral point grounding is prohibited.
User Manual 5 Electrical Connection