ytdivine:
What is Contact?
What does it mean?

A contact has only two states: open or closed. An open contact breaks the current flow whereas a closed contact allows current to flow through it to the next element. The simplest contact is an On/OFF switch which requires external force (e.g. the human hand) to activate it. Limit switches are those small switches that are placed at certain location so that when a mechanical device moves towards it, the contact will be closed and when the device moves away from it, the contact will be open.
a contact is connected to a load and the contact is closed, the load will be turned ON

ytdivine:


Our class rep @Southboy should note your name down and collect late registration fees

Thank you sir

doghorp:

A contact has only two states: open or closed. An open contact breaks the current flow whereas a closed contact allows current to flow through it to the next element. The simplest contact is an On/OFF switch which requires external force (e.g. the human hand) to activate it. Limit switches are those small switches that are placed at certain location so that when a mechanical device moves towards it, the contact will be closed and when the device moves away from it, the contact will be open.
a contact is connected to a load and the contact is closed, the load will be turned ON

Thank you very much. Good explanation

RELAY
You can't understand Automation without a good knowledge of relay logic.
Relay provides a good picture of ladder logic programming language. Relay consists of two things
a. Coil
b. Contacts
When coil is energized, the state of contacts changes. When de- energized, the state returns to original position.
I know by now everybody understands what coil is all about. Contact explanation will be made clearer as we progress.
Look at the picture of relay below and explain what you make out of it.

Class rep, am still expecting the list of inactive students

We are going to write an open test very soon. I will send an email address where you submit your answers to. Don't look down on what we are doing here. Many employers are following this thread.
You can't understand Automation and be poor for life. The employers look for you.
Please let's be serious in this class. Everybody should participate effectively

Nobody has responded to my question. Is the question tough? Even my number one student has not responded.
Do I need to explain the relay circuit all alone ? Nobody wants to stress his brain, why?

ytdivine:
RELAY
You can't understand Automation without a good knowledge of relay logic.
Relay provides a good picture of ladder logic programming language. Relay consists of two things
a. Coil
b. Contacts
When coil is energized, the state of contacts changes. When de- energized, the state returns to original position.
I know by now everybody understands what coil is all about. Contact explanation will be made clearer as we progress.
Look at the picture of relay below and explain what you make out of it.

Class rep, am still expecting the list of inactive students

When the coil is energized it produces a magnetic field. This magnetic field attracts the armature (movable contact). When the coil is de-energized the coil loose magnetic field and a spring retract the armature to its normal position.

doghorp:

When the coil is energized it produces a magnetic field. This magnetic field attracts the armature (movable contact). When the coil is de-energized the coil loose magnetic field and a spring retract the armature to its normal position.

Good job.
More inputs

Apologies I have been home since morning, I will send mine when I get home.

While we wait for others to respond, let consider the relay circuit.
Relay consists of two parts:
a. Coil
b. Contacts
When DC current is applied to the coil, the soft iron core becomes a magnet (Electromagnet) and attract the armature bar to it, closing the air gap. The Contact C changes state.
Contact is made up of two types
I. Normally Closed (NC)
ii. Normally Open (NO)
When the coil is energized, the NC becomes open and NO becomes closed
and vice versa when de-energized.

The change of States by the contacts is utilized in logic design while the coil being energized or de-energized is optimized in control.
In summary, the coil is used to control the states of the contacts

bestbiz17
Kingslaw
mosho2good
zealousayo
Akinzola
southboy
Jokolly
thedarkened
newusername
smartphil
eddyboy
bright12660
doghorp
cleardway4me
Username of everyone that has signified interest to join the class

Southboy:

bestbiz17
Kingslaw
mosho2good
zealousayo
Akinzola
southboy
Jokolly
thedarkened
newusername
smartphil
eddyboy
bright12660
doghorp
cleardway4me
Username of everyone that has signified interest to join the class

Good job

Southboy:

bestbiz17
Kingslaw
mosho2good
zealousayo
Akinzola
southboy
Jokolly
thedarkened
newusername
smartphil
eddyboy
bright12660
doghorp
cleardway4me
Username of everyone that has signified interest to join the class

Only active members will be given Automaton materials as gift

Study the symbols below used in Ladder Logic Programming

Input: Contact (whether NC or NO)
Output: Coil
Box contains the program

Southboy:

bestbiz17
Kingslaw
mosho2good
zealousayo
Akinzola
southboy
Jokolly
thedarkened
newusername
smartphil
eddyboy
bright12660
doghorp
cleardway4me
Username of everyone that has signified interest to join the class

Please add my name to the list, no time is too late to learn, I didn't have this kind of opportunity when I was still very young and eager to learn, now am getting old but I can still learn, no knowledge is loss.

ytdivine:
Study the symbols below used in Ladder Logic Programming

Input: Contact (whether NC or NO)
Output: Coil
Box contains the program

@Op, I can see that you are very knowledgeable in what you are doing, many people will not really understand the worth of the knowledge you are giving here for free. God bless you richly for what you are doing.

Will it be possible for me to contact you for industrial support/contract work in the field of automation if the need arises in the company were I work?
I myself am electrical engr. but I only get little knowledge of automation through self learning.

nnewsnjobs:


@Op, I can see that you are very knowledgeable in what you are doing, many people will not really understand the worth of the knowledge you are giving here for free. God bless you richly for what you are doing.

Will it be possible for me to contact you for industrial support/contract work in the field of automation if the need arises in the company were I work?
I myself am electrical engr. but I only get little knowledge of automation through self learning.

Thanks for the prayers.
It's quite unfortunate that the young graduates don't know the value of what am doing. I don't blame them because they lack the necessary exposure. Am doing this for conscience sake. Am already retired from field work having worked for over 15years.
However, I can provide technical support and in-house training depending on the time and location.
My own business borders on industrial electronics supply import and export. I have a network of friends across the globe for any industrial needs. aniobinnaeee@yahoo..com.

My primary concern is to raise young automation engineers that can take over the space occupied by the foreign expatriates in Nigeria

The major confusion student normally have is this normally open and normally closed contacts issues.
The best way to understand it is by testing a relay with multiple NC and NO.
This will form our practical number 3.
Please class rep take note.

ytdivine:


Thanks for the prayers.
It's quite unfortunate that the young graduates don't know the value of what am doing. I don't blame them because they lack the necessary exposure. Am doing this for conscience sake. Am already retired from field work having worked for over 15years.
However, I can provide technical support and in-house training depending on the time and location.
My own business borders on industrial electronics supply import and export. I have a network of friends across the globe for any industrial needs. aniobinnaeee@yahoo..com.

My primary concern is to raise young automation engineers that can take over the space occupied by the foreign expatriates in Nigeria

I feel you

ytdivine:
The major confusion student normally have is this normally open and normally closed contacts issues.
The best way to understand it is by testing a relay with multiple NC and NO.
This will form our practical number 3.
Please class rep take note.

Noted

Ladder Logic programming.
Consider the diagram below
We have entered into programming
What do understand from this logic program?
I stop here until I get minimum of 5 inputs from my students

If you don't have any idea just indicate

ytdivine:
Ladder Logic programming.
Consider the diagram below
We have entered into programming
What do understand from this logic program?
I stop here until I get minimum of 5 inputs from my students

The vertical line are power lines
The Horizontal lines are called rung or network
The Input are always connected on the left side of the Rung while the output are always connected on the right hand side of the Rung.
Power flow from left to right on the rung the flow of electricity will stop because the system is in NO (Normally Open contact) state.
The circuit shows that the logic program INPUT is in NO (Normally open) in other words the system is not energized. The output in the first rung is called -(S)- Set Coil while the output in the second Rung is called -(R)- Reset coil.

doghorp:

The vertical line are power lines
The Horizontal lines are called rung or network
The Input are always connected on the left side of the Rung while the output are always connected on the right hand side of the Rung.
Power flow from left to right on the rung the flow of electricity will stop because the system is in NO (Normally Open contact) state.
The circuit shows that the logic program INPUT is in NO (Normally open) in other words the system is not energized. The output in the first rung is called -(S)- Set Coil while the output in the second Rung is called -(R)- Reset coil.

Nice input. Remaining 4 inputs before I explain the diagram

I am interested.

BOLA625:
I am interested.

You're welcomed

Apologies for coming late to class today. I will be available tomorrow

I'm interested

danielukwuru:
I'm interested

You're welcome

ytdivine:
Ladder Logic programming.
Consider the diagram below
We have entered into programming
What do understand from this logic program?
I stop here until I get minimum of 5 inputs from my students

I have no idea

Individuals who have expressed interest in participating in the class are encouraged to make an effort to open the discussion thread, even if it's just once a day, in order to:

1. Review the latest posts.
2. Leave a comment to support the our lecturer who is dedicating time to share his knowledge.
3. Address any unanswered questions, if applicable.

Wishing you a pleasant weekend!

Nice thread here and it's cool.
What Youth can also look at is social media management it opens them to global market place to earn in foreign currency.