6.6. ElECTrICal CONNECTION
• Before putting the unit in place, make sure that the nominal supply voltage matches
that listed on the unit's identification plate.
• It should be installed with cables whose cross-section meets current regulations
and prevents overheating and voltage drops that exceed permissible limits. Current
regulations must be obeyed, and the designer's instructions must be followed at all
times.
• Before connecting the cables, make sure that the electricity is turned off and that
there is no voltage present in any of them.
• The installer must keep the following points in mind when performing the electrical
connections:
- An external control must be installed that operates the equipment.
- An emergency shut-off switch must be installed in the most accessible place
in order to stop the equipment in the event of a problem.
- The motors must be connected following the instructions in the wiring sche-
matics for the terminal boxes for the various motors. The equipment has
glands on the sides where the power is connected for running power cables
to the motors.
- A power outlet, fuse or "U" curve thermo-magnetic breaker must be installed
for each fan, which will protect each power line in the even of a short circuit.
- The general power line must have a fuse or "U" curve thermo-magnetic
breaker that will protect the mains power in the event of a short circuit.
- Interlocked contactors with a thermal relay are recommended for use to
protect against over-current.
• The instructions in current regulations regarding the protection of electrical lines
against defects and direct and indirect contact must be obeyed at all times.
• After these steps are performed, check to make sure all electrical connections are
secure (loose wiring connections can cause irreparable damage).
• Check to make sure the electrical resistance between earth and any electrical termi-
nal is greater than 1 megohms. If it is not, do not start up the unit until the electrical
short has been located and repaired.
• As a safety measure, if there is no power to the fan, the necessary interlocks must
be performed so that all other electrical components are also de-energised.
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