Introduction to battery-management systems- COURSERA WEEK 03 QUIZ -1.3.7 ANSWERS

 Introduction to battery-management systems- COURSERA WEEK 03 QUIZ -1.3.7 ANSWERS

Practice quiz for lesson 1.3.7

Total points 3

1.

Question 1

Consider a battery having $V_b=100$V. What is the minimum value of isolation resistance (in k$\Omega$) for the battery pack to be considered safe?

1 / 1 point

50

Correct

Yes. The minimum isolation resistance must be $500V_b=50,000$.

2.

Question 2

Consider a battery having $V_b=200$V. We measure $V_1=50$V and $V_2=150$V. If we insert a known resistance $R_0=200$k$\Omega$ on the negative-terminal side of the battery, then we measure $V_1'=48.3$V. If, instead, we insert a known resistance $R_0=200$k$\Omega$ on the positive-terminal side of the battery, then we measure $V_2'=145$V.

What is the isolation resistance of this battery pack (in $\Omega$)? Round your answer to the nearest $\Omega$.

1 / 1 point

9195

Correct

Yes. The possible isolation fault is on the negative-terminal side since $V_1<V_2$. We solve for isolation resistance using the equation on slide 5 and arrive at this answer. Since this resistance is less than $500V_b$, we determine that there is an isolation fault.

3.

Question 3

Consider a battery having $V_b=150$V. We measure $V_1=80$V and $V_2=70$V. If we insert a known resistance $R_0=100$k$\Omega$ on the negative-terminal side of the battery, then we measure $V_1'=40$V. If, instead, we insert a known resistance $R_0=100$k$\Omega$ on the positive-terminal side of the battery, then we measure $V_2'=35$V.

What is the isolation resistance of this battery pack (in $\Omega$)? Round your answer to the nearest $\Omega$.

1 / 1 point

187500

Correct

Yes. The possible isolation fault is on the positive-terminal side since $V_1>V_2$. We solve for isolation resistance using the equation on slide 7 and arrive at this answer. Since this resistance is greater than $500V_b$, we determine that there is not an isolation fault.