GB
6
4.2 - ELECTRICAL CONNECTIONS
4.2.1 - GENERALITIES:
• In all cases, refer to the wiring diagrams supplied with the unit or supplied upon request.
• The acceptable voltage variation is: ±10% during operation.
• The electrical connection conduits must be fixed.
• Short circuit current: 10 kA as per CEI 947-2.
• Class 1 unit.
• Use the holes fitted with grommets for passing cables into the unit.
• Use the stuffing boxes for passing cables into in the electrical box.
• The electrical installation must comply with the standards and regulations applicable where the unit is being installed (in
particular NFC 15-100
≈
CEI 364).
• The unit is designed to be connected to a main supply with a TT, IT or TN.S neutral point connection
(as per NF C 15-100).
• Electrical diagram
1005804
.
4.2.2 - GENERATOR POWER SUPPLY
• The power supply must be
three-phase 400 V / 50 Hz + Neutral
, in the electrical box directly on power switch S1.
CAUTION:
Before starting the unit, ensure that the phase rotation order is correct. The phase-sequence controller restricts
the unit from operating if the 3 supply phases are not in order or if a phase is absent.
• The power supply must come from an isolation and electric protection device (not supplied) in accordance with existing
regulations.
• The sizing of the power supply cables is to be ensured by the installer in accordance with the installation conditions and
as per current standards.
Cable sizes, indicated below, are given for information purposes.
They are calculated in accordance with NFC 15-100 (
≈
CEI 364) with the following hypotheses:
- Maximum current, see table below.
- Multi-pole copper cable with PR insulation.
- Installation in non-ventilated cable duct (installation method No. 41). No other power cable.
- Ambient temperature 40°C.
• The lengths indicated below correspond to a voltage drop less than 5% in the cable.
• The complete electrical specifications are given in the table of the technical documentation.
• Power to the frost resistor or supplementary heating must be separate from the installation.
4.2.3 - CONTROL BY EXTERNAL CONTACTS
A - PHRV WITHOUT SUPPLEMENTARY HEATING IN THE TANK (accessory)
• The machine is factory-wired for heating mode operation. The unit can be controlled remotely by connecting two good-
quality external potential-free contacts (not supplied):
- 1 for the remote On/Stand-by signal (contact closed = operation
authorized, contact open = stand-by),
- 1 for change-over of the operating mode (contact closed = heating
mode, contact open = cooling mode).
• The On/Stand-by signal is connected to terminals 1 and 2 of the PCB
located in the switch box (remove the existing bridge - see diagram).
• The mode change-over signal is connected to terminals 3 and 4 of the
PCB (remove the existing bridge - see diagram).
• The wiring of these contacts must not be routed near power cables in
order to avoid electromagnetic disturbances.
• Use shielded cable with twisted pairs (shielding grounded on
generator side).
• Max. connection cable length: 100 m.
• Minimum wire size: 0.5 mm
2
.
CAUTION:
Mode changes (Heating / Cooling) are to be performed with the unit shutdown.
B - PHRV WITH ELECTRIC SUPPLEMENTARY HEATING IN THE TANK (accessory)
•
The same as stated above, although in this case the command contacts are to be connected to the terminal in
the electric heater’s control box
(placed in the tank).
• See details in § 6.5.
2 2
2 5
3 2
3 6
Starting current
A
145
145
150
190
Max. total current
A
22.7
25.8
34
38.7
Power supply cable section
mm
2
6
6
6
10
Max. connection length
m
100
100
100
100
PHRV
1
2
4
3
PHRV
ON/Stand-by
Operating
mode
(
k
) Jumper to be removed
(
k
)
(
k
)
Printed
circuit
card
