5)Tighten the rear screws fully down on
Nettuno
HYDRAULIC CONNECTION
The 4÷20mA pressure sensor must be connected to the system delivery, preferably far from areas subject to
turbulence (bends, bypasses, branches, etc.) to ensure optimal stability of the measured signal.
It is a compulsory requirement to install an expansion tank with a capacity of at least 2-5 litres to ensure correct
shutdown of the pump and limit restarts caused by any small leakages which are common in most systems.
The pre-charge value of the tank must be suitable for the pressure values set. This will also help to keep the
operation constant in applications where water requirements are modest (e.g. for washing machines, toilet flushing
systems, etc.).
The system must also be equipped with a non-return valve to prevent the return of fluid to suction at the time of
pump shutdown. In the case of multiple installations, it is recommended to install a valve on suction for each pump.
CAUTION: when the pump stops, the conduits are still pressured so a valve must be
opened to bleed the system before any work is carried out.
INSTALLATION IN PUMPING UNITS WITH MULTIPLE PUMPS
Nettuno can be used to create pressurisation units with a maximum of 8 pumps, each controlled by an inverter. The
inverters are connected by means of a RS 485 serial connection. Each inverter is assigned an address, from 1 to 8,
for identification in the serial bus. To reduce costs, there is no need to install a pressure sensor for each inverter; a
single transducer is sufficient, connected to any one of the inverters (the address of the device hosting the pressure
sensor must be configured on the software of each inverter). Also any auxiliary 0-10 V control or digital input signal
must be connected to a single device. Serial communication deals consists in sharing the data of the pressure sensor
and digital inputs among the various connected inverters.
6) The bracket is designed for fixture of various
sizes of "U-shaped" hooks
refer to the diagram to select the correct version
.
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