What is the difference between closed and open chains?
Content
Electricity flows through a circuit and the circuit can be controlled to open and close as needed.
But sometimes the current may be interrupted or a short circuit may occur. Also, there are ways in which we can deliberately manipulate the chain to make it open or closed. To understand all this, we need to know the difference between open and closed loop.
Difference betweenn open and closed a circuit is that a circuit is open when there is a break somewhere in its path that prevents the flow of electric charge. It flows only when there is no such break, i.e. when the circuit is completely closed. We can open or close a circuit with a switch or protection device such as a fuse or circuit breaker.
I will explain this difference in detail with examples and illustrations, and then point out other differences for better understanding.
What is open and closed cycle?
open cycle
In an open circuit, no electric current can flow through it.
Unlike a closed circuit, this type of circuit has an incomplete path that is interrupted or broken. Discontinuity makes the current unable to flow.
closed circuit
In a closed circuit, electric current can flow through it.
Unlike an open circuit, this type of circuit has a full path without interruption or break. Continuity allows current to flow.
Illustrations
In electrical circuit diagrams, we usually indicate the open and closed part of the circuit with curved brackets and a thick dot, as shown in the figure below.
How to open a closed circuit and vice versa
A closed circuit can become open, or vice versa, an open circuit can become closed.
How can a closed loop become open?
If the current flowing through a closed circuit is interrupted, it becomes open.
A closed circuit can accidentally open if, for example, an open occurs somewhere in the circuit due to a broken wire. But the opening of a closed circuit can also be controlled intentionally or on purpose by switches, fuses, and circuit breakers.
Thus, an initially closed circuit can be opened by a broken wire by turning off the circuit breaker if a fuse is blown or a circuit breaker tripped.
How does an open circuit become a closed circuit?
If current begins to flow through an open circuit, it must be closed.
An open circuit can be accidentally closed if, for example, a connection occurs somewhere in the circuit due to incorrect wiring or a short circuit. But open circuit closure can also be controlled intentionally or on purpose by switches, fuses, and circuit breakers.
Thus, an initially open circuit can be closed due to incorrect wiring, a short circuit, a switch being turned on, a new fuse being installed, or a circuit breaker being turned on.
What happens when the circuit opens or closes
I will show you what happens in the case of a lighting scheme with one or two switches.
Single Derailleur Chain
A simple circuit with a single switch can only be connected in series with a load, such as a light bulb.
In this case, the operation of the light bulb is completely dependent on this switch. If it is closed (on), then the light will be on, and if it is open (off), the light will also be off.
This arrangement of circuits is common in high power circuits when we need to make sure that a device such as a water pump motor is controlled by a single switch.
Circuit with two switches
The two-key scheme also has practical applications.
What happens when a circuit opens or closes depends on whether the circuit is complete or incomplete and whether it is a series or parallel circuit.
Consider a circuit with two switches located at the top and bottom of the stairs to control one light bulb. The table below discusses all four possibilities for each schema type.
As you can see from the table above, BOTH switches must be turned on (or closed) in series for the light to come on. If one of them is off or both are off, the light will be off as it will open the circuit.
In a parallel circuit, only ONE of the switches must be on (or closed) for the light to come on. The light will only turn off if both switches are off, which will open the circuit completely.
For stairs, you should be able to turn off the lights with either the top or bottom switch, so you can see that a parallel arrangement is the most appropriate.
electrical theory
We can look at different aspects to understand the difference between a closed circuit and an open circuit in more detail. These differences are shown in the table below.
An open circuit is in the off state because the circuit is open or incomplete, while a closed circuit is in the off state because the circuit is continuous or closed. An open circuit does not allow current to flow, and there is no transfer of electrons or transfer of electrical energy. In contrast, an open circuit allows current to flow. Therefore, electrons and electrical energy are also transferred.
The voltage (or potential difference) at a break in an open circuit will be equal to the supply voltage and is considered non-zero, but in a closed circuit it will be almost zero.
We can also show another difference in resistance using Ohm's Law (V = IR). An open circuit will be infinite due to zero current (I = 0), but in a closed circuit it will depend on the amount of current (R = V/I).
| Aspect | Open circuit | closed circuit |
| Area | Open or OFF | Closed or off |
| chain path | Broken, interrupted or incomplete | continuous or complete |
| Current | No current thread | Current threads |
| nature | No electron transfer | electron transfer |
| Energy | Electricity is not transmitted | Electrical energy is transmitted |
| Voltage (PD) at breaker/switch | Equal to supply voltage (non-zero) | Almost zero |
| Resistance | Endless | Equal to V/I |
| Symbol |
Thus, a circuit is complete or functional only if it is closed, not open.
In addition to a complete and uninterrupted current path, a closed circuit requires the following elements:
- An active voltage source, such as a battery.
- The path is made of a conductor such as copper wire.
- A load in a circuit, such as a light bulb.
If all these conditions are met, electrons will flow freely throughout the circuit.
Take a look at some of our articles below.
- How to add a neutral wire to an existing light switch
- How to connect a light bulb holder
- How to test a circuit breaker with a multimeter
Help
(1) Leonard Stiles. Deciphering Cyberspace: Making the Most of Digital Communication Technologies. SAGE. 2003.
