چیە پۆلاریتی ڤێژینەوەی ترانسفۆرە؟

Transformasyonê Polarity Test çi ye?

Polarity Test Definition

Polarity test of transformasyon yek rêbaza dike ku ji bo parastina rastînayışê polarity hene lê bibêje dixwazin transformatoran bi paralel bexebitandin.

Dot Convention

Dot convention identifikirina polarity ê windings da di transformator de, û nîşan dide ku voltage yekemend e.

• Eger current di terminala dotted de werdike, ewa voltage yekemend di terminala dotted de ya dujimêr winding de positive be.

• Eger current ji terminala dotted de derbaske, ewa polarity ê voltage yekemend di terminala dotted de ya dujimêr winding de negative be.

Additive Polarity

Di additive polarity de, voltage yên navbera primary û secondary windings hatine zêdekirin, li ser transformatorên biçûk bikar anîn.

Subtractive Polarity

Di subtractive polarity de, voltage yên navbera primary û secondary windings difference ne, li ser transformatorên mezin bikar anîn.

Testing Procedure

• Circuit bi voltmeter (Va) across primary winding û another voltmeter (Vb) across the secondary winding bibêje xebite.

• Eger berdest bike, ratings û turn ratio ya transformatorê wereqet bike.

• Voltmeter (Vc) navbera primary û secondary windings bibêje xebite.

• Voltage bihêri primary side bibêje têne.

• Bi kontrolkirina value ê voltmeter (Vc), dibe dikarin bêtirin ku additive an subtractive polarity e.

If additive polarity – Vc should be showing the sum of Va and Vb.

If subtractive polarity – Vc should be showing the difference between Va and Vb.

Caution

Be careful that the max. measuring the voltage of voltmeter Vc should be greater than the sum of Va (Primary winding) and Vb (Secondary winding) otherwise during the additive polarity, the sum of Va and Vb comes across it.

Note

If additive polarity is needed but we have subtractive, we can fix it by keeping one winding as is and reversing the other winding’s connections. The same applies if we need subtractive polarity but have additive.