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A wattmeter is marked 15 A/30 A, 300 V/600 V and its scale is marked up to 4500 watts. When the meter is connected to 30 A, 600 V, the point indicated 2000 watts. The actual power of the circuit is

Power consumed by wattmeter = CT ratio x PT ratio x VIcosΦ

Plugging in the given values, we get:

2000 = (15/30) x (300/600) x VIcosΦ 2000 = (1/2) x (1/2) x VIcosΦ 2000 = (1/4) x VIcosΦ

Multiplying both sides by 4, we get:

8000 = VIcosΦ

Multiplying the given values of voltage and current, we get:

VI = 600 V x 30 A = 18000 W

Substituting this value in the above equation, we get:

8000 = 18000 cosΦ

cosΦ = 8000/18000 = 0.4444

Therefore, the power consumed by the circuit can be calculated as:

Power = VIcosΦ = 18000 x 0.4444 = 7999.2 ≈ 8000 watts

Hence, the actual power of the circuit is approximately 8000 watts.