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INSTALLATION
• This appliance must be permanently connected to fixed wiring and must be earthed.
• The wiring must be carried out by a competent person and be in accordance with the current IEE Wiring Regulations.
• Isolation device must be provided with a minimum contact clearance of 3mm.
• The MCB must be readily accessible and adjacent to the appliance.
7
8
7
8
5
6
5
6
3
4
3
4
1
2
1
2
L3 L2
N
L1
5
L3
3
4
L2
1
2
N L1
6
Power supply
3 x 400 V + N
Safety contactor
L3 L2
N
L1
5
L3
3
4
L2
1
2
N
L1
6
Power supply
3 x 400 V + Neutral
ELECTRIC CONNECTION / MODELS : 22 - 28 - 36
SIZING OF SUPPLY WIRES
the supply wires are sized depending of the type and current of the MCB, this last is firstly sized depending of the nominal current of the boiler.
The admissible current of the supply wires depends of the ambient temperature, the section and the length of the wires, the wires insulation,
the wires canalisation, the mounting type and the environment.
The following values are given for information for an ambient temperature of 30°C and a maximal length of 5 meters. In all the cases, the
installation must be in accordance with the current IEE Wiring Regulations.
16
25
32
40
63
80
1.5
2.5
4
6
10
16
Nominal current of the MCB
(A)
Nominal section
(mm
2
)