Onebutton Start Stop Only Use Relays and one button

[volkangun]

Hi for everybody,

I would like to give one question to the forum
Design one system which can start and stop one output by only using one button and relays nothing else more. Number of relays can be more than 3.

 

[Allen Nelson]

Key phrase: Flip-flop

PLC "relays" or physical ones?

The topic's been covered here more times than most of us care to think about.

 

[hesham]

No need for PLC

Connect your load directly to switch
On the switch the load will on
off the switch the load will of.
Very simple

 

[volkangun]

You can use both physical or internal relays

 

[volkangun]

Dear Hesham,
The condition is push button and only relays must be used.

 

[ArikBY]

The common way is like that

---------( )---------------(one shot relay)

      Push button               OSR



----------( )------( /)---------------(Out)

          Out    I   Out     I    

                 I           I 

----------( )-----(/)------- I

          osr     osR

WHEN YOU PRESS ON THE BUTTON THE RELAY GO ON WHEN YOU DO IT AGAIN IT GO OFF.

 

[hesham]

just kidding

volkangun
I am just kidding
I do it like this in the PLC.
press pushbutton
Increment a word
put a condition : is word=1
set the output
press pushbutton again
the word will be incremented again
put a condition: if word=2
reset the output&move zero to the word.
try it it works
thx

 

[volkangun]

Dear Arikby,

can you explain more your symbols out 1, out 2, I, osr ?
and I would like to tell you condition is only normal relays

 

[volkangun]

Dear Hesham,

Thank you for your reply
but the condition is; must be used only coils(relays) and their contacts.

 

[ArikBY]

What I made is good only for PLC.If you want to use physical relay
Use step relay.
OSR is one shot relay it function that give you pulse ON for one scan time of the PLC.

Out is any internal relay in the PLC

I is the vertical line between the horizontal lines.

 

[cnrservices]

They do make cyclic latching relays (not sure of thier exact name) that latch on & off with a single input. I remember my grandfather had one on his farm back in the 60's for an outside light on the barn, with a pushbutton at the house back door.

A standard contactor with a latching coil add-on deck would also do the same thing.

Your best net would be a smart-relay or micro-PLC which would probably be cheaper to buy & program 1 of them - than to buy, design & wire the bank of general purpose relays needed (and you still might need at least 1 one-shot timer)

Greg

 

[Mike Williams]

Allen wrote

PLC "relays" or physical ones?

Volkangun wrote

You can use both physical or internal relays

Arikby gave you a good example. Did you search the site on one shot?
Do you know what the hell a plc is/does?

 

[Mickey]

PB1 CR2 CR3 CR1
----||-----||---|/|--------------------------()

PB1 CR3 CR1 CR2
----||-----|/|---|/|-------------------------()
| CR2
|--||-------|

PB1 CR3
---||----------------------------------------()


CR2 is your output

Mickey

 

[cnrservices]

Mickey,

Where is the branch on line 2 connected? For proper formatting of ladders click on the LADDER button in the VB Code section above the reply window.

Greg

 

[panic mode]

Number of relays can be more than 3.

I don't know how to make it with more than three