The Inverter As Source Backup ("Smart Boost" Function); Input Current Controlled By Input Voltage - Studer XTH 3000-12 User Manual

In the case of mobile applications the installation of an RCC-02/03 remote control is
recommended, in order to be able to adapt the value of the input current limit if
necessary, for each connection to a limited grid.
If the power usage at the output is greater than the input limit current value {1107, the
Xtender cannot limit the current. This situation will then lead to the stoppage of the
generator due to overloading or will release the upstream protection circuit for the
Xtender. This major drawback can be prevented by using the "smart boost" function
described below. It is also possible to prohibit the beyond going of the current input imit
by the parameter {1436} which will then cause the opening of the transfer relay in case
of going beyond input limit.

6.2.6 The inverter as source backup ("smart boost" function)

The combined usage of the power sharing function and the smart boost function allows this
drawback to be overcome as mentioned above. The source backup function supplements
efficiently the charger current limiting function in order to ensure optimum protection of the fuse
upstream of the device. This system proves to be a decisive advantage particularly in all mobile
systems (boats, leisure vehicles and service vehicles) that are frequently connected to sources with
a limited value such as a portable or camping power supply. Despite a limited source, all the
greater power applications downstream of the Xtender remain functional.
When this function is activated, the battery can be fully discharged despite the presence
of the grid or the generator. The average power consumed by the user must not exceed
the power of the source, at the risk of discharging the battery.
The smart boost function is deactivated by default. To activate the function the RCC-02/03 remote
control is required. When this function is activated {1126}, it allows the current from the battery to be
supplied to the user in order to guarantee that the current at the input of the device does not
exceed the limit set {1107}.
If the input current limit is exceeded, the transfer relay will be opened immediately, thereby
protecting the upstream protection device. If the exceeding of the input current value limit is due
to a short-circuit downstream, the transfer relay will remain activated and the protection upstream
of the Xtender (H) will be requested.
The installation cabling must take this particular function into account, which allows a current
equivalent to the sum of all power outputs in the inverter and the AC source to be available at the
output.
If you have, for example, a 5 kW (22 A) source and an Xtender of 5 kW, the power available at the
output will be 10 kW. The downstream cabling must therefore be dimensioned accordingly. In this
example, the output cable must be dimensioned to support a current of 45 A. A dimensioning
table, fig. 1a, will help you to determine the output currents that dimension the protection devices
and the cable sections to be applied.
If the Xtender is connected to a generator, this must have a power at least equal to half
of the power of the Xtender(s) to which it is connected.

6.2.7 Input current controlled by input voltage

When AC sources with variable power are connected to the Xtender's ACin, a particular
parameter setting insure a permanent availability of the nominal power at the Xtender's output
thanks to the Smartboost function. It's notably the case with "Dynawatt" 230Vac alternator coupled
User manual V.3.1.0
STUDER Innotec
Xtender
23