On-Line, Real-Time, Programming...

[Terry Woods]

PeterW...

S5 was created by Siemens.

The S7 method was created by TI.

When Siemens bought TI-PLC, they named that last effort by TI to S7.

S7 was originally a TI device. It has since come to be more and more a device similar to S5.

To which I say... good going to worse.

S5 is nuts.

The original S7 was much more intuitive... despite the nay-sayers
of "intuitiveness".

It needed more, but certainly not in the direction of S5!

S5 is F$CKING CRAZY!

NOTICE: The aforementioned is nothing more than an opinion.

Get over it.

 

[S7Guy]

PeterW...

S5 was created by Siemens.

The S7 method was created by TI.

When Siemens bought TI-PLC, they named that last effort by TI to S7.

S7 was originally a TI device. It has since come to be more and more a device similar to S5.

That's not true. The S7-200 was influenced by TI, but the 300s and 400s are pure Siemens, and are very similar to S5. The 300/400 series have nothing to do with TI at all.

 

[S7Guy]

Simon, it was a 318. The Siemens rep told my client exactly as I wrote by the way.

Bob, I have had the same experience that Simon describes with a 315 (not sure if it applies to a 318). In fact, I had one 315 that would sometimes go into stop mode due to excess scan time when I was online. The 400 cpus have different resource allocations, so I doubt that the scan time would be affected.

 

[BobB]

I understand the 318 is a 400 processor in a 300 package. That may expain things. Interesting!

 

[kamenges]

Originally posted by SimonGoldsworthy:
From my experience a 315 increases it's scan time noticably whenever the programmer communicates with it - i.e. during the download of the block.

and

Originally posted by S7Guy:

In fact, I had one 315 that would sometimes go into stop mode due to excess scan time when I was online.

I only bring this up because of the subject of the thread. Keep in mind that the scan time change on the S7 during download is due to added communication load. It isn't related to anything the processor has to do to start running an updated block of code. As S7Guy stated, you can cause the same scan time issue by doing some heavy monitoring online.

Outside of this discussion, however, it probably doesn't matter what the source of the increase is. A stopped processor is a stopped processor.

Keith

 

[SimonGoldsworthy]

It isn't related to anything the processor has to do to start running an updated block of code

In order to start running an updated block of code it has to be downloaded to the plc and in the Step 7 environment it is very relevant as you cannot separate the action of downloading the block and then making the block active.

Conerning 318/315's, my understanding is that the 318 has a separate comms processor built in whereas in a 315 the CPU does it all. Even in a 318 the scan time does increase during comms activity, but generally not so you'd notice.

 

[Ken M]

Terry

"S5 was created by Siemens." - CORRECT

"The S7 method was created by TI." - INCORRECT

"When Siemens bought TI-PLC, they named that last effort by TI to S7." - INCORRECT

"S7 was originally a TI device. It has since come to be more and more a device similar to S5." - INCORRECT

"To which I say... good going to worse." - OPINION

"S5 is nuts." - OPINION

"The original S7 was much more intuitive... despite the nay-sayers of "intuitiveness"." - OPINION

"It needed more, but certainly not in the direction of S5!" - IRRELEVANT NONSENSE

"S5 is F$CKING CRAZY!" - OPINION

NOTICE: The aforementioned is nothing more than an opinion.

Wow - based on a total of one correct statement i.e. Siemens created S5 (nearly 30 years ago), you sure form a multitude of interesting opinions.
I'd hate to have you on the the jury that was deciding if I was for the gas chamber/electric chair/injection or whatever you people use these days.

Ken

 

[PeterW]

QUOTE=Ken M RE: Terry

"S5 was created by Siemens." - CORRECT 100% with Ken M

"The S7 method was created by TI." - INCORRECT I confur with with Ken M, although I believe TI DID have involvement with (not created) early S7, whether this was advice (for US market entry) through to developing the S7-200 range as someone suggested I have no idea. I was told this some time ago, may even have been when I worked for Siemens.

"When Siemens bought TI-PLC, they named that last effort by TI to S7." - INCORRECT 100% agree, S7 is Siemens and never TI

"S7 was originally a TI device. It has since come to be more and more a device similar to S5." - INCORRECT 100% agree with Ken M, S7 is Siemens

"To which I say... good going to worse." - OPINION an opinion that I believe totally incorrect.

"S5 is nuts." - OPINION another opinion I believe is totally wrong, Terry I believe you are another that dis-like something with which you are not too familiar (a human trait)

"The original S7 was much more intuitive... despite the nay-sayers of "intuitiveness"." - OPINION original S7 did not offer the tools that it does now.

"It needed more, but certainly not in the direction of S5!" - IRRELEVANT NONSENSE can't see what it needs

"S5 is F$CKING CRAZY!" - OPINION The only problem I ever had with S5 was communications, the simplest task was made difficult. I worked 100% AB from '81 through to '88 and then 100% Siemens from '88 to '96. I felt both were very good but Allen Bradley for me had the edge. Since S7 and Control Logix, I feel S7 has just taken the lead, although I have only been involved with Control Logix once, my opinion could change.

 

[BobB]

Conerning 318/315's, my understanding is that the 318 has a separate comms processor built in whereas in a 315 the CPU does it all. Even in a 318 the scan time does increase during comms activity, but generally not so you'd notice.

Explains a bit more. Thanks Simon. I might add I was unable to detect any change in scan time but when your head is down........

 

[JesperMP]

Terry, Ken, Peter.

I love to watch a fight from the sidelines, but isnt at least part of the discussion, due to the fact the "S7" includes both "S7-200" and "S7-300/400".

Terry may be referring to S7-200 and Ken and Peter may be referring to S7-300/400.

S7-200 seems to be more popular over there, and some people seem to take for granted that S7 means S7-200, wheras the opposite is the case over here. (This leads to confusing threads sometimes).

I aggree that S7-200 is a decendant of TI, there is no secret about it.
And S7-300/400 may be inspired by other PLCs, but its direct ancestor is S5.

 

[PeterW]

Terry, Ken, Peter.

I love to watch a fight from the sidelines, but isnt at least part of the discussion, due to the fact the "S7" includes both "S7-200" and "S7-300/400".

Terry may be referring to S7-200 and Ken and Peter may be referring to S7-300/400.

S7-200 seems to be more popular over there, and some people seem to take for granted that S7 means S7-200, wheras the opposite is the case over here. (This leads to confusing threads sometimes).

I aggree that S7-200 is a decendant of TI, there is no secret about it.
And S7-300/400 may be inspired by other PLCs, but its direct ancestor is S5.

fight, FIGHT, FIGHT.... FIGHT don't you mean lively discussion.



Your probably correct about 200's and 300's. Most companies I've worked for only use 400's. The only 200 I've come across is a filling line a couple of years back where they used a S7-200 for no can no lid detection. The line itself was controlled by a 416-2DP.

 

[Money4Nothing]

You guys are silly.

$

 

[n521554]

Terry,
I would like to ask the forum if anyone has every experienced any problems with online editing.

I have had 2 major/minor problems with online editing with AB PLC's. Major because they are a big problem when they happen, minor because they do not happen that often.

1. If the PC locks up, during edits being accepted, the editor may fill the processor with multilple copies of the same rung. This occured on PLC 5 processors across a busy DH+ network. This bug, if software related, may be fixed because I have not encountered it lately.

2. If you Test a large amount of rungs at one time you may cause the processor to crash on a watchdog timeout. Apparently, on PLC5's anyway, Test/Untest edits cuts into scan time.

Despite these 2 seldom seen got-ya's I love on line programming for developement and troubleshooting.

Wally

 

[Terry Woods]

Jesper is correct.

We were talking apples and oranges. I (we) failed to make the distinction between S7-200 and S7-300/400.

The PLC called S7-200 was developed by TI.

I have no idea what TI planned to call their new brick PLC - the one that ended up being called S7-200. For the sake of distinction, I'll call the original PLC, the one being developed by TI, the TI-S7.

I'm pretty sure that Siemens bought out the TI-PLC line before TI completed the design of the TI-S7. It might be the case that TI committed to finishing the design. In any case, Siemens had little choice but to continue with that design... at least for what ended up becoming the -200 version of the S7 line.

In terms of instruction concepts, the instruction set used by the original TI-S7 was very similar to the instruction set available in TiSoft.

The S7 method... that is, the programming instruction set that existed on the TI-S7 PLC, before it came to be known as the Siemens S7-200, was developed entirely by TI.

It was Siemens that decided on the name "S7-XXX". No doubt to make clear that the new line was the next generation, beyond S5.

The PLC called S7-300/400 was developed entirely by Siemens.

As I recall, Siemens rolled out the S7-200 and then, later, the S7-300/400.

At the beginning, it was very clear that what ended up being the S7-200 software was very, very, different from S7-300/400 software.

I have no idea when Siemens began developing the S7-300/400, but it was clear, at least at the beginning, that the software used in the S7-300/400 was certainly more closely related to the software used in S5 than to the software used in the S7-200.

However, I expect that it won't be long before the software is more similar than dissimilar, and that the S7-200 software will have moved more towards the S7-300/400 version rather than the other way round.

 

[S7Guy]

I remember discussing this with some Siemens developers in about 1994 or so, and the original intent was that the S7-200 would be able to be programmed with the 300/400 software. Obviously, that never happened, probably because the 200 processor is just too different and it wasn't worth the effort.