Simulate power dissipation on freewheeling diode

This circuit is for a Block Occupancy Detector and associated signal. The signal is normally green, but when a train enters the block, it switches the signal to red. The debouncing will mitigate any bad indications the train has left the block prematurely.

This design is intended to show how our basic technology building block models can be combined to represent the essential physics and electrical behavior of a more complex component. In this case, an electro-magnet and simple mechanical elements are used, together with an ideal electrical switch and some technology converter blocks, to models an electro-mechanical relay.

When the relay is energized and closes, the lamp lights up! You can even see contact bounce in the armature position waveform (green waveform), and its impact on the lamp inrush current transient (blue waveform).

The relay model is built hierarchically from

https://www.systemvision.com/design/relay-assembly-model

To use it in another design, simply right-click on the relay symbol and select, "Add Favorite." The relay model will then show up in your "My Favorites" category.

When a pushbutton is pressed, the lift will go up or down, via switching relays

connected to a motor, depending on its posiion known by limit switches on the top and bottom.

(if its at the top it will go down or if its at the bottom it will go up)

it allows the user to stop it midway during operation by pressing the same pushbutton

and pressing again will cause the lift to go in the opposite direction.

The lift will not go up if there is a weight on the top of it, the weight of a car in a real

life situation.

The circuit:

* relay1 attached from pin 8 to ground

* relay2 attached from pin 9 to ground

* pushbutton attached to pin 4 from +5V

* 10K resistor attached to pin 4 from ground

* pushbutton attached to pin 2 from +5V

* 10K resistor attached to pin 2 from ground

* Limit switch attached to pin 5 from +5V

* 10K resistor attached to pin 5 from ground

* Limit switch attached to pin 3 from +5V

* 10K resistor attached to pin 3 from ground

created 2016

modified 11 Jun 2016

by Shane Willoughby

基于双路继电器制作的带进位全加法器