Quick S5 DW question

Hi

I'm looking through some S5 software that is using DB's populated with DW's.

The PLC is connected to an HMI where an operator can key in how many packs he wants the machine to produce. The complaint I recieved was that if he wanted to put in more than 32,000 packs the system wouldn't take it. So, if for instance he needed 38,000 packs, he had to key in 32,000 then keep an eye on it and add another 6,000 packs when it had finished.

I assumed that the DW was using a signed INTeger and that it would only go from -32,767 to +32,767 (hence the 32,000 limit).

Is there a way of checking how the datablock is configured? Or is there a way of changing the DW to hold more than 32,000?

I know that in S7 you can configure a DW to be either a WORD or an INT. And that a WORD will hold up to 65,535. Is this the same for S5?

I must admit that on the face of it, it seems that the S5 software is using WORDS and the restriction might actually be from the HMI as oppose the PLC...

Anyone got any info on this?

Cheers

JT

Johnny

I think that in S5, there is no facility for unsigned INT only signed INT. If you want to be able to input more than 32,767 then you will need to reconfigure the DB to KG format (floating point) then load the DD in place of the DW in your program.

I am basing this answer on the data formats permitted in a S5 DB, which are KM: bit pattern, KH: hexidecimal, KY: 2 bytes, KF: fixed point number (which you are using), KG: floating point number, KS: character, KT: timer value and KC: counter value.
Paul

Paul

Thanks, as always, for the informed reply. I was also going to ask (in the original question) what the format pnemonics meant ie. KY KF KH etc but you answered that as well without me even asking.. that is impressive!...


Cheers mate

JT

If your HMI will allow data above 32k to be entered, you can use a dw to store 0-65535. When you load the number, just treat it as if its a double word for comparisons etc.

Perhaps a quick and dirty hack ?

Leave everything as it is inside the program and only change the counting logic in the PLC that way that only every tenth pack the produced value would increase.

If operator fills in 3800 then 38000 packs would be produced. As you are talking about big quantities it might be workable for your operators and could probably easyily implemented.

If you'll post the program I'll give it a look.

Good Luck

Simon and Flukie

2 excellent responses there. I'll look into whether the comparison is done only in the HMI, if it is I'll do as you suggest and use a normal word in the PLC but handle it as a double word in the HMI.

If not, I'll try flukies idea.

As I said, 2 great ideas. Many thanks

JT