Learning Step 7

[JesperMP]

Yes, I noticed post #4, but it looks as it was ignored. It is like trying to get the toothpaste back in the tube.

 

[L D[AR2P#0.0]]

I love that analogy (especially if it is stripey toothpaste).

 

[L D[AR2P#0.0]]

Examples showing the use of S5 timers and IEC timers. Uses function blocks and instance Data blocks.

 

[asterof]

I did not ignore it, it just made no sense to me
Lets break it down

S5T#4S
Bold part is your problem.
To understand this, you need to know how the S5 time is built.

S5 time is only 1 word, 2 byte, 16 bits.
Of those 16 bits, the 2 MSB's are not used. This being bit 14 and 15.
Bit 12 and 13 together form a binary number which makes the time base.
00 = time base is 10ms
01 = time base is 100ms
10 = time base is 1s
11 = time base is 10s
The following 12 bits is expected as a BCD number.

It looks something like:

NNTT XXXX XXXX XXXX

N = not used
T = time base
XXXX = BCD number (0-9 in hex)

The BCD x Time base = S5 time.
This setup limits the timer to 9990s. (BCD 999 and time base of 10s)

As uptown said, this effectively limits the timer to 2h46m.

As some other will no doubt mention: Seeing that you're just starting with Siemens, make it a habit to use IEC timers now.


To understand this, you need to know how the S5 time is built.
S5 time is only 1 word, 2 byte, 16 bits.
Of those 16 bits, the 2 MSB's are not used. This being bit 14 and 15.
Bit 12 and 13 together form a binary number which makes the time base.
00 = time base is 10ms
01 = time base is 100ms
10 = time base is 1s
11 = time base is 10s
The following 12 bits is expected as a BCD number.
It looks something like:
NNTT XXXX XXXX XXXX

Why is NN even there if it is not used, makes no sence to me

N = not used
T = time base
If T is time base should it not be a number?

XXXX = BCD number (0-9 in hex)

The BCD x Time base = S5 time.

Based on this info I would expect the string to look like
S5 23 00 00 01
so u see it makes no sence

again S5 = indicates a timer
T = ?? a number as indicated above ?
# = who knows ?
4 = some number for something ?
S = seconds ?

To me it indicates
S5 = indicates a timer
T = 10 so i second
# = I see no reason for this
4 = 4
S = seconds

so it is a timer with a 4 second preset

 

[asterof]

mis spelled words

would not let me edit and correct
sorry

 

[PeterW]

Why is NN even there if it is not used, makes no sence to me

Because a 14 bit word does not exist.


I think the reference to Post 4 was more to do with IEC timers rather than the meat of the post.

 

[PeterW]

S5T = Format

# = delimiter between format and data

rest = data

 

[asterof]

So the S5T is a fixed prefix required by the software
indicating a type of timer
# is a fixed delimiter always required by the software
Data is a string indicating the time base and time preset multiplied
by the time base
I think I have it now
Thanks all

 

[L D[AR2P#0.0]]

Forget it and move on to IEC timers.

 

[asterof]

PeterW, left you a private Question on your answer above.

 

[KalleOlsen]

Hi, asterof!

Finding certain items in the Siemens web complex is more like the needle/haystack mare, but have you checked this Siemens tutorial site? Could be some needles in there for you.

https://www.automation.siemens.com/mcms/sce/en/advanced_training/training_material/download_training_material/Pages/Default.aspx

Kalle