Class H open dry transformers
The useful life of transformers depends strongly on the state of their insulation, controlling their state in regular periods or on special occasions, incipient failures can be predicted, thus avoiding catastrophic consequences.
With an adequate maintenance program it is possible to increase the reliability of the transformer and with it that of the system in which it is connected.
ROUTINE TESTS
-
Transformation relation
-
Winding resistance
-
Insulation Resistance
OIL TESTS
-
Dielectric strength
-
Color
-
Interfacial tension
-
Specific gravity
-
Goo
-
Neutralization number
PHYSICAL MAINTENANCE
-
Cleaning
-
Dry air application (Dry transformers)
-
Equipment physical condition review
-
Review of installed components
-
Status of connections and installations (cabin)
-
Complete restoration of paint and marking (on site)
-
Preventive diagnosis
-
Programming of future activities according to preventive and predictive maintenance planning.
Maintenance contact
Jorge A. Quevedo
Angelica Sarmiento
Fabian Vargas
Class H open dry transformers
Nacional de Transformers - TESLA designs and manufactures open dry three-phase transformers with class H insulation in powers from 30 kVA to 5 MVA and voltage levels up to 36 kV .
TESLA is a specialist in the manufacture of low voltage transformers series 1.1 / 1.1 kV, medium voltage 36 / 1.1 kV and 15 / 1.1 kV, according to the NTC, IEC-EN or ANSI standard.
.
They are designed with a temperature rise of the windings 125 ° C or less, cooled by natural or forced air, winding material: Copper / Copper , Copper / Aluminum , Aluminum / Aluminum .
.
K-factor designs for harmonic control. (K1, K2, K4, K6, K9, K13, K20, K30), low losses in the core and in the windings, predisposed for indoor installation with protection cell ( IP 20 to IP 40 ) and outdoor installation with protection NEMA 4 and IP 55 .
.
Low voltage coils are manufactured on automatic power winding machines. The conductive materials generally used are tape (foil) or rectangular plate, with class H insulation (180 ° C) ; the medium voltage coils are manufactured in comb type biscuits with enameled round wire and; They are manufactured on high speed and precision automatic machines.
.
The magnetic core is made of grain oriented electrical steel, high magnetic permeability and low losses. Each sheet of magnetic steel is insulated by a thin layer of organic material (Carlite), the cut is 45 degrees and its columns are stacked using the " Step Lap " method, reducing hysteresis losses and vacuum currents, guaranteeing low noise level.
On request, a temperature monitor with thermocouples type PT 100 and a connection box for thermal protection of the transformer is supplied. They are delivered or installed SPD for protection against overvoltages and forced ventilation system for power increase of up to 30% of the nominal value; There are also bimetallic connectors for the connection of the copper - aluminum connection or vice versa.
.
Transformers suitable to meet the electrical energy requirements in sectors such as:
Industries
Oil sector
Malls
Urbanizations
Residential buildings
Hospitals
Any other installation for indoor use