s7-200

Hi and a happy new year. If anyone can help in my problem, in order to have also a good year.

Çow can i measure an analog signal every 5 seconds, continuously and automatic, with s7-200 of siemens in STL?

I did it, but i have to push a switch in every cycle of the programm.

dimpol

I am not really sure what you mean by your question, but here goes:-

why not just use a 5 second timer, re-triggering it and then using the done bit to grab your analogue values.

Network 1

LDN M0.0
TON T33, +50

Network 2

LD T33
= M0.0

Network 3

LD M0.0
GRAB YOUR ANALOGUE VALUE HERE

T33 is a 10ms timer, M0.0 is the retriggering contact.

If that is what you are trying to do then maybe that will give you a start.

Paul

THANKS VERY MUCH PLucas. GO MANCHESTER UND?


NETWORK 1 // Create table with 100 entries starting with memory location VW4
LD SM0.1 // On the first scan,
MOVW +100, VW0 // define maximum length of table

NETWORK 2

LDN M0.0
TON T33, +50

NETWORK 3

LD T33
= M0.0

NETWORK 4

LD M0.0
ATT AIW4, VW0 // copy value of memory location VW100 to table

NETWORK 5
LD SM 1.4 // set 1 if the table is overfill
FIFO VW100, VW400 // remove the first entry of the table to VW400



I WANT TO MEASURE AN ANALOG SIGNAL EVERY 5 sec AND TO STORE THE 100 RECENTLY VALUES.

IS IT CORRECT?

IF I WANT TO STORE MORE THAN 100 VALUES, HOW CAN I DO IT? BECAUSE THE TABLE CAN STORE ONLY 100 (98) VALUES…

Dimpol

At first glance your example will work, but, without actually testing it, I can't give you a definate answer. I don't have the necessary hardware in my possesion.

As for the table length, the only limit is the CPU memory, which is 1kb for a 212, 4kb for a 214 and 5kb for a 215 and 216.

So if you are using a S7 212, you should be able to record up to 512 words, (memory area VB0 to VB1023), surely that is plenty.

I have not worked a lot with S7 200's, so I might not be totally correct on that, maybe one of the other regulars who works with 200's can chip in with some advice, I believe Terry Woods does quite a lot with these machines.

One point to note: you wrote:-

GO MANCHESTER UND?

Click to expand...

I support my local team - Gillingham Football Club, ( http://www.gillinghamfootballclub.com ) and like the vast majority of soccer fans in this country I have no interest in Manchester United, in case you get the wrong impression, I have not taken offence to you writing that.

Paul.

Thanks PLucas.

I know your team. There is a channel here in greece that shows games from the 1st division of England. There are some greek players in your Championship.

I' m PANATHINAIKOS (WWW.PAO.GR). Today we won a big match 3-2, from 1-2, against olympiakos.

Thanks again
bye.