Question

Question 3) The measured value of loop impedance for a circuit is 0.83 ohms. If the

temperature at the time of the test was 20°C and the cable is 70°C (factor 1.2) what is the
corrected value? (Ze = 0.40)
a) 0.916 ohms
b) 0.86 ohms
c) 0.996 ohms
d) 0.43 ohms

PLEASE NEEDED WITHIN 5 MINUTES

Answer 1

So, the corrected value of the loop impedance is 0.996 ohms, which is option (c).

Step-by-step explanation:

To correct the measured loop impedance (Zm) for temperature, you can use the formula:

Zc = Zm × (1 + α * (Tc - Tm))

Where:

Zc = Corrected loop impedance

Zm = Measured loop impedance

α = Temperature coefficient of the cable material (assumed to be 0.004 per °C for copper)

Tc = Cable temperature (70°C)

Tm = Measured temperature (20°C)

Plugging in the values:

Zc = 0.83 ohms × (1 + 0.004 * (70°C - 20°C))

Zc = 0.83 ohms × (1 + 0.004 * 50°C)

Zc = 0.83 ohms × (1 + 0.2)

Zc = 0.83 ohms × 1.2

Zc = 0.996 ohms