A dry type transformer is defined as a transformer that does not use any liquid as an insulating or cooling medium for its windings or core. Instead, the windings and core are enclosed in a sealed tank that is filled with air or gas under pressure.

Dry type transformers are widely used in various industries and applications because of their safety, reliability, and environmental benefits. They can operate in harsh conditions such as high humidity, fire risk, and seismic events without compromising their performance or posing any hazard to people or property.

 

 

Nominal power rating	50 kVA
Nominal voltage rating	11 kV
Frequency	50 Hz
Insulation class	F
Cooling method	AN/AF
Primary voltage range	±5%
Secondary voltage range	±2%
Vector group	Dyn11
Efficiency	≥96.5%
Short circuit impedance	4.5%
Noise level	≤ 60dB (A)
Temperature rise limit	95°C
Environmental conditions	Indoor or outdoor application with shelter
Standards	IEC 60076, ANSI C57.12.01

 

 

 

Some of the main advantages of dry type transformers are:

● They are safe for people and property because they do not contain any flammable or toxic liquid that can leak or catch fire.

● They are maintenance-free and pollution-free because they do not require any oil changes, oil tests, oil spills cleanup, or special disposal methods.

● They are easy to install because they do not require any vaults or special foundations. They can be placed close to the load to reduce the need for long and costly low voltage cables.

● They are environmentally friendly because they do not emit any harmful gases or contribute to the greenhouse effect.

● They have an excellent capacity to support overloads because they have better heat dissipation and thermal endurance than oil-filled transformers.

● They have reduced costs on civil installation works and fire protection systems because they do not need any oil containment pits, fire walls, fire extinguishers, or sprinklers.

● They have excellent performance in the case of seismic events because they have a rigid structure that can withstand vibrations and shocks.

● They have no fire hazard because they have self-extinguishing properties and do not produce any smoke or flames in case of faults.

● They have excellent resistance to short-circuit currents because they have low impedance and high mechanical strength.

● They are long-lasting due to low thermal and dielectric heating because they have high-quality insulation materials that can withstand high temperatures without degrading.

● They are suited for damp and contaminated areas because they have high moisture ingress protection and corrosion resistance.

 

 

Dry-type transformers have many benefits, such as safety, reliability, environmental compatibility, easy installation, low maintenance, excellent overload capacity, reduced cost, excellent performance, no fire hazard, excellent resistance, long-lasting life, and suitability for damp and contaminated areas.

However, dry-type transformers also have some drawbacks, such as higher cost, larger size, heavier weight, higher sensitivity, and higher noise than oil-filled transformers.

 

 

 

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