Italtecnica Nettuno 3P-13A Manuel D'instruction page 37

DIGITAL OUTPUTS
Two digital relay outputs are available for signalling
operation status. The relays can be configured via the
software independently, to perform one of the following
functions:
- error signalling
- pump running signal
- control of an electric pump at fixed speed,
connected directly to the mains via a power relay
Refer to the parameter settings section for further details on
configuration of the digital outputs.
RS 485 SERIAL CONNECTION
Up to a maximum of 8 inverters can be connected to the RS 485 serial
port to create multiple pump pressurisation units.
There are two terminal boards on each device for the serial connection,
to enable cascade connections of multiple inverters, as shown in the
figure alongside.
A non-shielded cable with a section of 4x0.5mm
this connection.
To make the connection, connect the terminals "+", "-", "A" and "B" of
one device to the same terminals of the next device, and continue in the
same way until all inverters are connected in the same communication
bus.
No special terminal at the end of the bus is necessary.
CAUTION: after connecting the devices to one another, they should
be assigned an individual number to identify their address in the
serial bus. Each device must be assigned a different number;
otherwise, if several devices have the same address, the serial
communication will overlap with loss of transmitted data.
2
is recommended for
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