Fronius Primo GEN24 3.0 Plus, Operating Instructions Manual, Page: 76 / 160

The following points regarding cabling must be considered:
- The main contacts of contactors K1 and K2 must be installed between the Fronius
Smart Meter and the inverter and the residual current circuit breaker of the backup
power circuits.
- The supply voltage for contactors K1 and K2 is provided by the public grid and must
be connected to phase 1 (L1) after the Fronius Smart Meter and fused accordingly.
- An NC contact for the relay K3 interrupts the supply voltage to contactors K1 and
K2. This prevents the backup power network of the inverter from being switched to
the public grid.
- The NO contact of relay K3 gives feedback to the inverter on whether the locking
was successfully performed by relay K3.
- Additional inverters or other AC sources can be installed in the backup power circuit
after the main contacts of K1 and K2. The sources are not synchronised to the net-
work of the inverter because this backup power network has a frequency of 53 Hz.
- The use of contactor K2 is optional in Australia.
All-pin separation
cabling variant
e.g. Germany,
France, Spain Circuit Diagram
The Circuit Diagram for the 2-pin double separation - e.g. Germany, can be found in the
appendix to this document on page
149 .
The Circuit Diagram for the 2-pin single separation - e.g. France and Spain, can be
found in the appendix to this document on page
150 .
Cabling of backup power circuit and non-backup power circuits
If not all the loads in the home need to be supplied in a backup power situation, the cir-
cuits need to be divided into backup power circuits and non-backup power circuits. The
total load of the backup power circuits must not exceed the nominal output of the
inverter.
The backup power circuits and non-backup power circuits must be fused separately
according to the required safety measures (residual current circuit breaker, automatic cir-
cuit breaker, etc.).
In backup power mode, only the backup power circuits are disconnected at all pins from
the grid by contactors K1 and K2; an earth connection is only established for these cir-
cuits. The rest of the home network is not supplied with power in this case.
76