Transformer
manufacturers in India, Rajasthan Powergen can solve many problems involved in
transformer installation by adopting best practices. The difficulties and
safety hazards can be minimised by taking care of certain factors while
positioning a transformer. Location has an impact on how the transformer should
be set up and the precautions to be
taken in the future.
The
Standards
Installing transformers complying with the ANSI, NEMA, and IEEE standards is important in ensuring safe electrical installation and reliable power supply system which is highly important when power quality is an issue.
Installing transformers complying with the ANSI, NEMA, and IEEE standards is important in ensuring safe electrical installation and reliable power supply system which is highly important when power quality is an issue.
Transformers
can be a challenge in terms of NEC requirements . Correctly designed
installation will make sure the conductors and equipment are right sized,
protected and deal with the issue of grounding. Incorrect installation can lead
to fires from improper protection or conductor sizes and electric shock from
inadequate grounding.
Installation
Best Practices Some of the particularly important transformer installation best
practices are listed below:
1. Permanent
Grounding:As soon as the transformer is
placed permanently the tank should be permanently grounded with a correctly
sized and properly installed permanent ground before assembling the unit and
carrying out the inspection.
2. Humidity: Nobody should be allowed to access the transformer
liquid-filled compartment in case of
excessive humidity or rain. Whenhumidity exceeds 70% , dry air should be
continuously pumped into the gas space. Liquid-filled transformers with Nitrogen
in the gas space must be purged by pumping dry air for 30 minutes before
service personnel can enter the tank. Oxygen concentrations of 19.5% to 23.5%
are recommended.
3. Fluid
Inspection: When the insulating liquid
needs to be drawn out for inspection, always keep make equipment for clean and
dry storage of the liquid during inspection and for filtering the liquid before
refilling the tank. Make sure that all associated equipment used in the
handling of the fluid (hoses, pumps, etc.) are also very clean and dry. When
you remove the liquid, its level should not go below the top of windings.
4. Pressure
maintenance: Sufficient gas pressure should
be maintained to allow a positive pressure of 1 psi to 2 psi all the time, even
at low ambient temperature. The pressure-vacuum gauge, will show pressure
variations with ambient temperature. Pressure and ambient temperature readings
should be recorded .
5. Inspection
and filling: Final inspection of the
transformer should be done before it is energized, especially if any work has
been done inside the tank. All the electrical connections should be checked for
tightness. All bushings should be checked for tightness of gaskets. Electrical
clearances inside the tank should be checked. One final check should be made to
ensure all tools have been removed.
6. Loading: The transformer should be kept under observation
during the first few hours of operation under load after applying full voltage
. After few days of working, check the oil for oxygen content and dielectric
strength. All temperatures and pressures should be checked in the transformer
tank during the first week of operation. Except for special designs,
transformers may be operated at their rated kVA if the average ambient
temperature of the cooling air does not exceed 86'F (30'C) in any 24-hr period,
and the altitude does not exceed 3300 ft.
7. Surge
arresters: surge arresters must be
installed and connected to the transformer bushings/terminals with the shortest
possible leads. These arresters may be necessary to protect the equipment from
line switching surges and lightning.
8. StructuralConsiderations: Multiple transformers can be mounted on a single
pole as long as the weight is evenly distributed, and the total weight is well
within the safe limits of the pole.
9. Mounting: Sub-100 kVA single-phase distribution transformers
are typically mounted above the secondary mains.
10.
Protection: all distribution transformers must have lighting arresters
and fused cutouts installed on the primary side.
11. Groundwires: Cover all ground wires with plastic or wood molding
to a point 8 feet above the base of the pole.
12. Guying
of poles: Correctly installed guy wires
can protect the pole line from damage caused by the strain of the line
conductors and pole-mounted equipment.
Hence
following the best practices, the transformer manufactures in India, Rajasthan
Powergen can reduce costs and prevent safety hazards. Keeping in mind the type
of transformer to be installed, its purpose and its surroundings during
installation is surely a way to minimize hazards.