INSTALLATION AND
PROGRAMMING INSTRUCTIONS
SUNWAY M XS 7500TL
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5.3.1. Connection to the LV Grid
The maximum allowable number of inverters that can be connected to the LV grid is 63.
According to the regulations in force governing the connection to the LV grid of photovoltaic generators, the
maximum single-phase power must not exceed 6 kW. In case of plants comprising multiple inverters with
overall power exceeding 6 kW, the inverters are to be installed on a three-phase grid and the inverters are to
be evenly distributed over the three phases. It must be considered that the difference between the power
delivered over two phases must never exceed 6 kW.
When maximum N.3 inverters are connected and the overall power of the PV plant is lower than 20 kW, no
particular solution is required, except if one of the 3 inverters is a SUNWAY M XS 7500TL. In that specific
case, the Power Balance function described in 5.3.3 is to be activated.
When more than three inverters are utilized or when the overall power of the PV plant is higher than 20 kW,
all the three inverters must be simultaneously disconnected from the grid when the grid voltage or frequency
is out of the allowable range. In that specific case, the Power Balance function described in 5.3.3 is to be
activated.
When the overall power of the PV plant is higher than 20 kW, galvanic separation between the plant and the
grid is required.
5.3.2. Connection to the MV Grid
The maximum allowable number of inverters that can be connected to the MV grid is 100.
No power balance limit between the phases is imposed by the regulations in force governing the connection
to the MV grid of photovoltaic generators. Consequently, the Power Balance function is not required for the
connection to the MV grid. However, it is recommended that the installed power of the connected inverters
be evenly distributed among the three phases.
5.3.3. Power Balance
NOTE
The connected inverters should be evenly distributed among the three
phases, so that the difference of the power installed between two phases is
not over 6 kW.
The SUNWAY M XS inverters feature an integrated Power Balance function limiting the difference among
the power delivered over the three phases in a multi-inverter multiplant according to the allowable ranges.
Once the Power Balance function has been configured and activated, the inverters exchange their
production data in real time via an external CAN bus. Based on these data items, the inverters connected to
each individual phase will automatically limit the delivered power in order not to exceed the power unbalance
in respect to the other phases.
Communications among the devices connected to a multi-inverter plant is made via CAN connection made
available by a dedicated 5-pole M12 circular connector located on the bottom side of the inverter enclosure
(see Figure 75 and Figure 76).
The CAN connector pin-out is shown in Figure 81.
Figure 81: CAN connector
