1
GATE EE 2004
+2
-0.6
A single-phase load is connected between $$R$$ and $$Y$$ terminals of a $$415$$ $$V,$$ symmetrical, $$3$$-phase, $$4$$-wire system with phase sequence $$RYB$$. A wattmeter is connected in the system as shown in figure. The power factor of the load is $$0.8$$ lagging. The wattmeter will read
A
$$-795$$ $$W$$
B
$$-597$$ $$W$$
C
$$+597$$ $$W$$
D
$$+795$$ $$W$$
2
GATE EE 2004
+2
-0.6
A dc A-h meter is rated for 15 A, 250V. The meter constant is 14.4 A-sec/rev. The meter constant at rated voltage may be expressed as
A
3750 rev/kWh
B
3600 rev/kWh
C
1000 rev/kWh
D
960 rev/kWh
3
GATE EE 2003
+2
-0.6
The voltage-flux adjustment of a certain $$1$$-phase $$220$$ $$V$$ induction watt-hour meter is altered so that the phase angle between the applied voltage and the flux due to it $${85^0}$$ (instead of $${90^0}$$). The errors introduced in the reading of this meter when the current is $$5$$ $$A$$ at power factors of unity and $$0.5$$ lagging are respectively
A
$$3.8$$ $$mW,$$ $$77.4$$ $$mW$$
B
$$-3.8$$ $$mW,$$ $$-77.4$$ $$mW$$
C
$$-4.2$$ $$W,$$ $$-85.1$$ $$W$$
D
$$4.2$$ $$W,$$ $$85.1$$ $$W$$
4
GATE EE 2003
+2
-0.6
A wattmeter reads $$400$$ $$W$$ when its current coil is connected in the $$R$$ phase and its pressure coil is connected between this phase and the neutral of a symmetrical $$3$$-phase system supplying a balanced star connected $$0.8$$ $$p.f.$$ inductive load. The phase sequence is $$RYB.$$ What will be the reading of this wattmeter if its pressure coil alone is reconnected between the $$B$$ and $$Y$$ phases, all other connections remaining as before?
A
$$400.0$$
B
$$519.6$$
C
$$300.0$$
D
$$692.8$$
EXAM MAP
Medical
NEET