## Quiz sheet for three phase delta connected systems

To correctly connect three windings, A, A1; B, B1and C, C1 in delta, the wiring connections would be:

A) A1 to B, B1 to C and C1 to A

B) B1 to C1 to Al1

C) A to B to C

D) A to B1, B1 to C and C to A1

In a delta connected system the angle between the line current and the phase current is:

A) 0°

B) 30°

C) 90°

D) 120°

The ratio of  the line voltage to the phase voltage in a delta connected system is:

A) 1:1

B) 1:1.414

C) $$\sqrt{3}$$:1

D) 1:1.732

The resultant voltage around a closed delta connection is calculated from the:

A) phasor sum of the phase voltages

B) phasor difference of the phase voltages

C) algebraic difference of the phase voltages

D) numerical sum of the phase voltages

The line voltage of a delta connected system is approximately:

A) the same as the phase voltage

B) half the phase voltage

C) 1.73 times the phase voltage

D) 57.8% of the phase voltage

The available power from an open delta connected transformer compared to a delta connected transformer is:

A) 57.7%

B) 33.3%

C) 66.7%

D) 50%

The resultant voltage around the closed loop of a delta connected transformer with one phase winding reversed is:

A) twice the phase voltage

B) equal to the phase voltage

C) half the phase voltage

D) zero

The ratio of line current to phase current in a delta connected system is:

A) 1.73:1

B) 1:1

C) 1:1.73

D) 1.414:1

If a delta connected load has one supply line open circuited then there will be:

A) equal current in two phases

B) zero current in one phase

C) equal current in all phases

D) zero current in all phases

The resultant voltage in a correctly closed delta system is equal to:

A) Zero

B) Phase voltage

C) Line voltage

D) 1.73 times phase voltage