![background image](http://html1.mh-extra.com/html/calpeda/nc-series/nc-series_original-operating-instructions_4055751003.webp)
3. Electric mains connection
The pumps NC, NCD are provided with a built-in three-phase electric motor to be connected to a.c. mains of
3x400V, 50Hz. The electric motor is provided with a thermal cut-out that will switch off the electric motor by
means of a relay or contactor when it is overheated. For each version a device isolating all the poles from the
mains has to be built into a fixed installation, with a gap of 3mm between open contacts.
The connecting wire has to be connected over a cable entry Pg 16 (Fig. 4 – Pos. 7), and has to be "T" version
due to the pump warm-up being higher than 50K.
The pump versions NCM, NCDM are provided with a built-in single-phase electric motor 1x 230V, 50Hz.
The electric motor is provided with a thermal cut-out that will switch it off when it is overheated.
4. Electrical connection of pumps
The electrical connection of pumps has to be carried out according to the wiring diagram (Fig. 4 – Pos. 14)
that is glued on the motor cover (Fig. 4 – Pos. 3) up to the connecting terminals (Fig. 4 – Pos. 13).
In Fig. 4, Pos. 12 a male and female parts of connector are designated, they are put together when the pump
is operating.
5. Setting operating characteristics of pumps
Each pump is able to cover three hydraulic fields, and for this reason such pumps are provided with electric
motors for three different speeds. The characteristics or speed desired (3, 2, 1) can be selected using the
connector marked with an arrow (Fig. 1 - Pos.2).
Set the speed as follows:
a) Disconnect the pump from the mains by switching off the ON-OFF switch.
b) Pull out the button of the three-position connector (Fig. 1 – Pos. 2) on the electric motor cover (Fig.
1 – (Pos. 3), rotate it to the speed desired (1, 2, 3), and push it down to end stop.
c) Connect the pump to the mains using ON-OFF switch.
A nominal permissible pressure for the pump is NP6/10bar. Maximum pressure height is 11m water column.
The ambient temperature of the pump is 0 to 40°C.
6