A solenoid is a magnetic switch that uses low
current to close a high current circuit. The solenoid has
an electromagnet with a core (6) which moves.
SCHEMATIC OF A SOLENOID
1. Coil. 2. Switch terminal. 3. Battery terminal. 4.
Contacts. 5. Spring. 6. Core. 7. Component
There are contacts (4) on the end of core (6). The
contacts are held in the open position by spring (5) that
pushes core (6) from the magnetic center of coil (1).
Low current will energize coil (1) and make a magnetic
field. The magnetic field pulls core (6) to the center of
coil (1) and the contacts close.
The circuit breaker is a safety switch that opens
the battery circuit if the current in the electrical system
goes higher than the rating of the circuit breaker.
A heat activated metal disc with a contact point
completes the electric circuit through the circuit breaker.
If the current in the electrical system gets too high, it
causes the metal disc to get hot. This heat causes a
distortion of the metal disc which opens the contacts and
breaks the circuit. A circuit breaker that is open can be
reset after it cools. Push the reset button to close the
contacts and reset the circuit breaker.
CIRCUIT BREAKER SCHEMATIC
1. Reset button. 2. Disc in open position. 3.
Disc. 5. Battery circuit terminals.