What is the effect on time constant of transient current, as a result of resistance commutation?(a) Remains same(b) Decreases(c) Increases(d) Increases then decreasesI got this question in my homework.My question is based upon Commutation Process -1 in division Commutation Process & Excitation Methods of DC Machines

What is the effect on time constant of transient current, as a result

1.	What is the effect on time constant of transient current, as a result of resistance commutation?(a) Remains same(b) Decreases(c) Increases(d) Increases then decreasesI got this question in my homework.My question is based upon Commutation Process -1 in division Commutation Process & Excitation Methods of DC Machines
Answer» Correct choice is (d) INCREASES then decreases The explanation is: We add high contact resistance between commutator segments and brushes thus, it adds resistance to the CIRCUIT of the commutating coil THEREBY reducing the time constant (L/R) of the current transient (IC(t)), helping it to change faster in the desired DIRECTION.

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