I want to use one normally open contact to work as ON button

one normally closed contact to work as OFF button

one relay

one light source

+5V supply and ground

the same +5V is the power supply for light source also

Now my question is as follows:

When I hit ON the light should stay ON unless I hit OFF

Once I hit OFF the light should stay OFF unless I hit ON

How should I connect these contacts alongwith the relay to achieve the above?

If anyone has an idea please let me know

Thanks

 

I want to use one normally open contact to work as ON button

one normally closed contact to work as OFF button

one relay

one light source

+5V supply and ground

the same +5V is the power supply for light source also

Now my question is as follows:

When I hit ON the light should stay ON unless I hit OFF

Once I hit OFF the light should stay OFF unless I hit ON

How should I connect these contacts alongwith the relay to achieve the above?

If anyone has an idea please let me know

Thanks

Is this homework? You can lie, but God will get you.

 

Hint: You use the relay contact to power itself when ON.

The rest you should be able to figure out.

 

Sorry but I could not figure out even using your hint

 

i tried different ways but still couldn't make it work

 

If this is homework, you won't learn much by getting it handed to you, but here it is.

 

Sorry but I could not figure out even using your hint

crutschow's hint requires the use of a DPDT relay. One set of contacts will be used for his hint. The other set of contacts will be used for your application.

This is my hint.

How much experience do you have working with relays and electronics? I could give the answer but will you have learned anything? Experimentation, in my opinion, is part of the fun of learning.

 

no its not homework

i am trying to learn ladder logic

came across this question

but in your solution once the NO contact opens i think the coil will get de-energised and the relay contact will open

then how will 5V appear across lamp????

 

How much experience do you have working with relays and electronics? I could give the answer but will you have learned anything?
_______________________________________________________________

I have never worked with relays before

 

no its not homework

i am trying to learn ladder logic

came across this question

but in your solution once the NO contact opens i think the coil will get de-energised and the relay contact will open

then how will 5V appear across lamp????

The NO switch energizes the relay when it is depressed. The relay contacts close, keeping the relay on and lighting the lamp. The NC contacts release the relay, breaking the circuit.

 

Well since it is ladder logic you could use an (OTL) and (OTU) instructions for your output.
OTL = Output Latch
OTU = Output Unlatch

The OTL and OTU instructions will use the same address.

Does this help?

 

i read the relay concept again

you are right thanks a lot

Is there any specific tutorial you would recommend to learn ladder logic?

I want to be good in plc programming

Thanks again

 

As for the relay part...

I believe this is what crutschow was talking about doing...

 

crutschow's hint requires the use of a DPDT relay.
...........................

No. Since the same power is used to power the relay that powers the light you only need a SPST relay.

 

i read the relay concept again

you are right thanks a lot

Is there any specific tutorial you would recommend to learn ladder logic?

I want to be good in plc programming

Thanks again

look at http://thelearningpit.com/

They have a fairly useful program that is free to try for around 30 days or so. After that you have to buy a key.

 

No. Since the same power is used to power the relay that powers the light you only need a SPST relay.

Okay. I know what you thought of then.