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XSTORAGE HOME 3P INSTALLATION MANUAL
MN700009EN August 2020 www.eaton.com
00 Title
4.3.2 Maintenance charge
During the winter period or after long periods of inactivity, the battery may remain at the minimum state
of charge for a long time with the risk of a deep discharge phenomena with consequent risk of structural
damage to the internal cells. Therefore, to avoid damages of the battery, the control module integrated in
the battery (BMS) may require the xStorage Home 3P hybrid inverter to carry out a maintenance charge.
The maintenance charge brings the state of charge from the minimum value to a value determined
by the BMS based on the state of health of the cells. The charging current is also determined by the
BMS module based on the health and temperature of the battery itself.
The duration of the maintenance charge depends on the energy available from the solar panels and
on the health of the cells of the battery. This process can take a long time (hours) especially during
the winter when the available solar energy can be very low.
The maintenance charge status is shown on the display status bar.
WARNING:
The maintenance charge is a safety function of the battery to avoid damages. For this
reason, the xStorage Home 3P hybrid inverter can activate grid charging if the available photovoltaic
energy is not enough.
WARNING:
During the maintenance charge, normal system functionalities are disabled, and the
battery cannot be used by the system. All system functionalities are automatically restored at the
end of the maintenance process.
WARNING:
During the maintenance charge the EPS mode is disabled. It is automatically restored
at the end of the maintenance process.
WARNING:
Maintenance charge is required by the battery integrated control module (BMS). The
xStorage Home 3P hybrid inverter cannot in any case disable the command from the battery.
4.4 Protective devices
To ensure maximum performance, xStorage Home 3P systems have been designed without transformer,
i.e. without galvanic isolation between the DC input and the AC output. Therefore, in order to ensure a safe
operation and to comply with current standards even without an isolation transformer, the xStorage Home 3P
systems have been fitted with all the required safety devices, as described in the following sections.
4.4.1 Anti-islanding
The xStorage Home 3P system is equipped with an advanced anti-islanding protection system, i.e. with a
protective automatic disconnecting system that is enabled in the event of a grid power outage or of voltage and
/ or frequency faults detected on the grid in order to avoid off-grid operation, which could be dangerous for the
grid operators who work on the grid and for the loads connected to it. The safety system is fully compliant with
the national relevant standards and legislation.
4.4.2 Earth leakages of the PV panels
The xStorage Home 3P system must be used with PV panels isolated by a ground wire (earth), i.e. with the
positive and negative terminals without direct connections to ground. To this effect, a built-in protective and
monitoring circuit constantly monitors the connection to ground and disables the xStorage Home 3P system
when a fault is detected on the system by immediately displaying the associated alarm through the graphic
user interface.
The xStorage Home 3P system can only be used with PV systems compliant with Class A specific
requirements, in compliance with IEC 61730 standard requirements.
