Adjustable RL Current Ramp

Application

Use this circuit to explore current buildup in solenoids, relays, and inductive loads.

Design Context

A 5 V source drives a resistor and variable inductor. Transient UIC starts inductor current at zero.

Expected Behavior

The inductor current rises toward the resistor-limited steady-state value; larger inductance slows the ramp.

Key Values

• V1 is 5 V.
• R1 is 100 ohm.
• LV1 ranges from 1 mH to 50 mH.

Suggested Experiments

• Change LV1 position and compare the current ramp.
• Increase R1 to reduce final current.
• Change the transient end time for slower inductance settings.

Featured Component

The variable inductor component computes its effective inductance from the position setting.