ytdivine:
On the coil with soft iron core, the iron absorbs the magnetic field to become a temporal magnetic. The magnetic property is lost the moment the current is removed.
In summary,
The iron core becomes temporal magnet.
The iron core becomes normal iron, no more magnet, once the current is removed.

Here we get a situation where a material that's not originally a magnet, becomes one by simply applying a DC current to it.
This is what is called ELETRO - MAGNET.
We are gradually entering into CONTROL.

ytdivine:
From @Southboy contribution, not the word TEMPORAL. This is very important.
Still need more inputs

Southboy:
Do you mean "note" or "not"?

ytdivine:
I hope by now everybody has understood what Electromagnet is all about. This play very vital role in automaton and control industry. Let's consider the practical applications.
a. Bell application
When the doorbell button is pressed, it completes the electrical circuit, allowing current to flow through the coil of wire in the doorbell. The coil of wire becomes an electromagnet, producing a magnetic field around it. This magnetic field repels the soft iron amateur, which is connected to a spring. As the soft iron is repelled by the electromagnet, it compresses the spring. When the doorbell button is released, the circuit is broken, stopping the flow of current and thus turning off the electromagnet. The spring then pushes the soft iron amature towards the electromagnet, creating the characteristic "ding" sound.
When you understood this simple application, the same principle is applied in complex application.
The diagram below is open to the house for discussion.
Everybody get involved. What happen when current flows through the circuit?
That's when the switch is closed

ytdivine:
Let get proper into the job. Class rep @Southboy, lock the class doors,We have not bought padlock sir, lol. make sure no student gets out.
Everybody must answer these questions:
From the bell diagram above, identify
a. The action control Doorbell button (the one that gets pressed)
b. The action itself Attraction of the iron to the electromagnet and the subsequent "ding" sound.
c. The input(Signal) Pressing the doorbell button (completing the circuit)
d. The output The audible "ding" sound when the iron hits the bell, indicating someone is at the door.

Correct answer attracts #500 recharge card from me

ytdivine:
Now, everybody pay attention. This is a serious business.
What type of activities is represented in the bell circuit?
ON and Off bell
Is this activity digital or analog in nature?
Digital
What's the input signal for digital?
5vdc or 24vdc
What's the result of switch the circuit ON and OFF?
Inductor coil is Energized /De-Energized
What happens when the input is 1?
Coil is Energized
What happens when the input is 0?
Coil is de-energized
What's the out?What does this mean?
Coil
What action is triggered by the output?
Bell

Please study this over and over and ask your question

ytdivine:
Now, everybody pay attention. This is a serious business.
What type of activities is represented in the bell circuit?
ON and Off bell
Is this activity digital or analog in nature?
Digital
What's the input signal for digital?
5vdc or 24vdc
What's the result of switch the circuit ON and OFF?
Inductor coil is Energized /De-Energized
What happens when the input is 1?
Coil is Energized
What happens when the input is 0?
Coil is de-energized
What's the output?
Coil
What action is triggered by the output?
Bell

Please study this over and over and ask your question

ClearDway4me:
Wow, just find this group when searching for something relating to automation.

God bless you op. I will fully once am done with exam but for now include my name in the class list

ytdivine:
Who can tell me what this symbol represent

ClearDway4me:
Wow, just find this group when searching for something relating to automation.

God bless you op. I will fully once am done with exam but for now include my name in the class list

ytdivine:
Who can tell me what this symbol represent

ytdivine:
People should respond when I ask question. I don't like beating students but may start doing so if am forced to it.
Class rep, compile the list of class members that don't answer question.
I need the list tomorrow morning.
At long run, I shall present gifts to active students

ytdivine:
Who can tell me what this symbol represent

Southboy:
Auxiliary contact(Normally open contact)

ytdivine:
What is Contact?
What does it mean?