Sound Levels - HPS EnduraCoil 1.2 KV Manual De Instrucciones

Location (continued)

Sound Levels

Installation, Operation, and Maintenance Guide - Cast Resin Transformers
Dry-type transformers should not be installed in areas
accessible to the public unless specially designed for this
application.
Dry-type transformers can be located outdoors, but they must
be designed especially for outdoor environmental protection.
Suitable weather resistant and tamper-proof enclosures are
required in locations where transformers may be exposed
to driven water, snow, dust and sand particles. Consult the
transformer manufacturer for further information.
Transformers with open bottom, should not be installed on or
over combustible surfaces.
Transformers must be located at least 2 feet away
from walls, obstructions, adjacent transformers or
other reflecting surfaces on the ventilation side unless
otherwise marked on nameplate. Transformers should
not be located near other heat sources or obstructions
that may affect their ventilation and increase the
ambient temperature.
Directed air in the room near the transformer can disturb
the natural air flow for cooling through the winding.
Adequate ventilation is essential for the proper cooling of
transformers. Clean, cool, dry air is desirable. If the location
has unusually high airborne contaminants, optional filters may
be required. If transformers are installed in vaults or other
places with restricted air flow, sufficient ventilation shall be
provided to maintain correct air temperatures. The limits are
specified by CSA and ANSI standards and are measured near
the transformer ventilation openings. The area of ventilation
openings required depends on the height of the vault or
transformer room and the location of transformer ventilation
openings. For self-cooled transformers, the required effective
area must be at least one square foot each of inlet and outlet
per 100 kVA of rated transformer capacity, after deduction of
the area occupied by screens, gratings or louvers.
This is necessary to provide sufficient free circulation of air
through and around the transformer. This will also permit ready
access for maintenance.
If the transformer is to be located near combustible materials,
the minimum distance established by The Local Electrical
Fire Code should be maintained.
The audible sound produced by transformers is due to
energizing of the core by the alternating voltage applied to the
windings. This creates vibrations whose fundamental frequency
is twice the frequency of the applied voltage. The vibrations
producing audible sound can occur in the core mounting and
in the housing. The transmission of sound from the transformer
can occur by various media such as air, metal, concrete, wood
or any combination. Amplification of audible sound can
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