Model a solenoid with spring return. When unpowered, the spring pulls the plunger +5mm away from the center of the coil. Turning on the power supply at t=0.1 seconds pulls the plunger into the center of the coil. At t=0.3s, a 10N external load is added to the plunger.

Model a transformer using fundamental magnetic library blocks. The transformer is rated 50W, 60 Hz, 120V/12V and assumed to have an efficiency of 94%, no-load magnetizing current of 1% and a leakage reactance of 2.3%. Core losses are not modeled and the core material B-H characteristic is assumed to be linear.