Electrical Connections; Figure 9: Power Supply Connection - Riello NXHP Series Installation, Operation And Maintenance Instructions

2 - INSTALLATION OF UNIT

2.4 - Electrical connections

Please refer to the certified wiring drawings, supplied with the unit appliance shall be installed in accordance with national wiring
regulations.
2.4.1 - Power supply
The power supply must conform to the specification on heat pump
nameplate. The supply voltage must be within the range specified
in the electrical data table. For connections refer to the wiring
diagrams and the certified dimensional drawings.
CAUTION:
As a standard protection, it is mandatory to install a
disconnect switch to be able to disconnect the power supply
of the unit.
Make sure to respect the wiring order to avoid electrical
shock.
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Note: Recommended scredrivers for wiring
- 5 x 1 mm flat scredriver (power terminal block)
- 2 x 0.5 mm flat scredriver (control terminal block)
2.4.2 - Recommended wire sections
Wire sizing is the responsibility of the installer, and depends on
the characteristics and regulations applicable to each installation
site. The following is only to be used as a guideline, and does not
make Manufacturer in any way liable. After wire sizing has been
completed, using the certified dimensional drawing, the installer
must ensure easy connection and define any modifications
necessary on site.
The connections provided as standard for the field-supplied power
entry cables are designed for the number and type of wires, listed
in the table below.

Figure 9: Power supply connection

10
10
40
10
10
60
The use of an ATEX disconnect switch is mandatory if it is
installed at less than one meter of the unit.
During the installation of the unit, only the side panel must
be removed. The top panel shall not be removed at any time.
After the unit has been commissioned, the power supply must
only be disconnected for quick maintenance operations (one
day maximum). For longer maintenance operations or when
the unit is taken out of service and stored (e.g. during the
winter or if the unit does not need to generate cooling), water
circuit and water heat exchanger must be drained.
This unit is equipped with electrically powered safety
measures. To be effective, the unit must be electrically
powered at all times after installation, other than when
servicing.
Customer electrical connection - 1Ph
Customer electrical connection - 3Ph
The calculations of favourable and unfavourable cases are
performed by using the maximum current possible of each unit
(see the tables of electrical data for the unit).
The calculation is based on PVC or XLPE insulated cables with
copper core. A maximum ambient temperature of 46°C has been
taken into consideration. The given wire length limits the voltage
drop to < 5% (length L in metres - see table below).
IMPORTANT:
Before connection of the main power cables (L1 - L2 - L3 - N
- PE or L1 - N - PE) on the terminal block, it is imperative to
check the correct order of the 3 phases before proceeding to
the connection and the good connection of the neutral wire
(if the neutral conductor is not connected correctly, the unit
can be damaged permanently).
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