Quiz sheet for transformer losses and cooling

A dry transformer housed in a louvered enclosure that relies on convection for cooling would be designated as 

A) AN

B) ON

C) ONAN

D) OFAN

ANSWER: A

A transformer rating is determined by 

A) the size of the conductors used in the windings

B) the viscosity of the transformer oil

C) type of material used for the windings of the transformer

D) it's ability to dissipate heat

ANSWER: D

A transformer that is housed in a tank of mineral oil with an external tank that is cooled by fans would be designated as 

A) OFAF

B) ONAN

C) ONAF

D) ONAN/ONAF

ANSWER: A

Dry transformers are cooled by 

A) ambient air

B) dry ice

C) oil with no moisture content

D) refrigerant 

ANSWER: A

The limiting factor for temperature of an oil immersed transformer is 

A) flash-point of the transformer oil

B) the winding resistance

C) the insulation breakdown temperature

D) the boiling point of the oil

ANSWER: A

The rating of a transformer can be increased by 

A) improving the cooling method

B) adding turns to the primary

C) adding turns to the secondary

D) decreasing the ventilation

ANSWER: A

The test that is performed on a transformer to determine the iron losses is called a 

A) no load test

B) short circuit test

C) loss test

D) magnetic test

ANSWER: A

The test used to determine the copper loss in a transformer is called a 

A) short circuit test

B) No load test

C) full current test

D) overload test

ANSWER: A


Last modified: Monday, 31 May 2021, 8:41 PM