Electrical Wiring - Hitachi SET FREE Serie Manual De Instalación Y Funcionamiento

Electrical wiring

10 ELECTRICAL WIRING
10.1 GENERAL INFORMATION
C A U T I O N
• Before any work to the electrical wiring or regular inspections,
switch off the mains power supply of the indoor and outdoor
units. Wait three minutes before starting installation or main-
tenance work.
• Make sure that the interior and exterior fans have come to a
complete standstill before starting work on the electrical wir-
ing or regular inspections.
• Protect cables, the drainage pipe, electrical components, etc.
from rodents and insects; otherwise these might damage un-
protected components and this could result in fire.
• Do not allow cables to come into contact with the refrigerant
pipes, metal edges, printed circuit boards (PCB) or the elec-
tric components inside the unit; the cables may be damaged
and this could result in fire.
• Firmly secure the cables inside the indoor unit with plastic
flanges.
10.2 GENERAL VERIFICATIONS
1 Make sure the electric components supplied by the fitter (main
power switches, circuit breakers, wires, connectors and con-
nection terminals) have been selected correctly in line with
the electrical data given.
a. The electricity supply to the unit should be via an exclu-
sive power control switch and protective circuit breaker,
certified and installed in accordance with local or national
safety regulations.
b. Connect the power supply wiring for each group of indoor
units to its outdoor unit group (maximum capacity for each
group of indoor units: 26 HP). Do not mix units of different
groups.
c. For heat recovery systems, the CH unit and the indoor
unit of the same refrigerant cycle can be supplied from the
same mains power switch.
2 Check that the supply voltage is between 90 and 110% of the
rated voltage. Where the voltage capacity is too low, it will
not be possible to start the system due to the drop in voltage.
3 Sometimes, the refrigeration/heating system is not able to op-
erate correctly in the following cases:
• When the system is supplied from the same supply line as
other major consumers (heavy machinery, power inverter
systems, cranes, welding machinery, etc).
• When the supply cables of the major consumers and the re-
frigeration/heating system are very close together.In these
cases, induction in the wiring to the refrigeration/heating sys-
tem may arise due to a rapid change in the electricity con-
sumption of the above consumers and their start-up. There-
fore before starting installation work, check the regulations
and standards concerning adequate protection of the power
supply line.
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D A N G E R
• Use an earth leakage breaker with medium sensitivity,
and an activation speed of 0.1 or less. If this is not fitted,
there is a risk of electric shock and/or fire.
• Install an earth leakage breaker, fuse and circuit breaker
for each outdoor unit power line. Not fitting it may cause
an electric shock or fire.
N O T E
For further information, please refer to the applicable legislation
in the country in which the unit is to be fitted.
4 During the preliminary preparation work of the electricity sup-
ply line for the unit, the provisions in local and national legisla-
tion must never be violated.
5 Check that the earth cable is correctly connected.
D A N G E R
• Never connect the earth cable to the refrigerant pipes.
The gas in the pipes could cause a fire.
• Do not connect the earth cable to the lighting rod. The
electrical potential of earth would increase abnormally.
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