1
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
2
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
$$4.2$$ $$W,$$ $$85.1$$ $$W$$
3
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
$$692.8$$
4
GATE EE 2000
+2
-0.6
The two wattmeter method is used to measure active power on a three phase, three wire system. If the phase voltage is unbalanced, then the power reading is
A
affected by both negative sequence and zero sequence voltages
B
affected by negative sequence voltages but not by zero sequence voltages
C
affected by zero sequence voltages but not by negative sequence voltages
D
not affected by negative or zero sequence voltages
EXAM MAP
Medical
NEET