start stop station

how do you wire a start stop station using slc 500

I am sorry, I can not resist

One wire from stop to input 1
One wire from start to input 2

Here is the answer to today's homework question.

If it really is a homework question then I'm reasonably sure that something on this will have to be modified - even though this is how it would be done in industry - it is just a bit different from a typical homework assignment - so if you can spot the difference then you likely understand what you need to do and so I dont feel too bad about doing your homework.

I liked Ron's answer better Alaric! LOL

I guess it's personal preference, but I always put the stop before the start. I guess I do it that way because actual wiring is done that way.

stasis said:

I guess it's personal preference, but I always put the stop before the start. I guess I do it that way because actual wiring is done that way.

Click to expand...

Me two..But i do believe (If memory serves correct) that it HAd to be done on the older TI PLC's..? (Cant remeber the model but it was all numbering was in base 7)

I think Alaric was posing a "what do you do". The poster asked how to "WIRE", not how to program.

I am in favor of assisting students but they MUST learn to ask for what they need and be willing to show some effort.

rsdoran said:

I am in favor of assisting students but they MUST learn to ask for what they need and be willing to show some effort.

Click to expand...

Which is why I used an example with three inputs. A typical homwork lab assignemnt would probably not specify a starter contact. I presume that if the student can modify it from there, then he would be able to understand the solution. But then again, mayby not. And, If he submits it as is, and the instructor has been around the block a time or two, he would know the solution came off the internet, but then again, maybe not.

 

student submits      instructor is         student

internet solution      an idiot            flunks

+-----] [----------------]/[-----------------( )

 

Either way works, in hardware or software... either way is commonly used, in hardware or software... and I can't imagine that there was ever a restriction on which came first in a PLC... certainly not in a TI.

After all... how can a PLC tell the difference between a Start button and a Stop button? Each input is nothing more than an input!

I simply prefer to code a Start/Stop like so...

    Start     Stop        MTR

  ---| |---+---| |-------(   )

           |

     AUX   |

  ---| |---+

.
...only because I like to have the rung "funnel" down to the output.
The benefit becomes more apparent as the number of conditions and condition-combinations for the particular output increases.

In TiSoft, the code listing is Left-Justified. I've seen some listings from other PLCs that are...what... Center Justified? ...no... Distributed? Yeah, that's the word, Distributed. The elements are evenly distributed across the full width of the maximum width allowed. I don't like that... too much "white" between elements.

For some people... taste is only in their mouths.

I really like Alaric's logic in Post #8.


.....casey

stasis said:

I guess it's personal preference, but I always put the stop before the start. I guess I do it that way because actual wiring is done that way.

Click to expand...

If the stop is programmed first, this will take 1 more instruction than programming the stop last.
Start First =
LD Start
OR Aux
AND Stop
OUT Motor
Stop First =
LD Stop
LD Start
OR Aux
ANDLD
OUT Motor

Just a thought...
Paulus

Compared to what?

stasis said:

I guess it's personal preference, but I always put the stop before the start. I guess I do it that way because actual wiring is done that way.

Click to expand...

Actual wiring as compared to what other kind of wiring?

randylud said:

Actual wiring as compared to what other kind of wiring?

Click to expand...

as opposed to software...

since most schematics show the stop first, then the start, that's the same way I do it in software...
stop start coil
---I I----I I---( )--

add locking/holding contacts as needed.

I find that a screwdriver or pocket knife work better for wiring.
PLCs do not fit in the little holes that the screws hide in.