Siemens Profibus Issue?

Hi
I have a problem with a new installation.

PLC is node 2, HMI 1 is node 3 and HMI 2 is noode 4

If I view accesible nodes I see everything, and can prove the hmi node address by powering down a node

If I download to node 3, node 3 is overwritten. If I download to node 4, node 3 gets overwritten.

Weird behaviour, and yes i checked the nodes profibus address under transer..advanced..profibus

I am using WinCC Flex 2008 SP3

Also what is the thinking behind 'only master on the bus'

Cheers

Are you POSITIVE when you press the transfer button
that you are down loading to 4 (your station address is not set to 3)
see pic
I know, I really read your post- just checking
that is odd

Yes I am.
Although I have made the mistake before

Maybe I need to apply > exit transfer, and reopen transfer and check it has accepted the node change.

I tried an ethernet transfer and the panel would not accept it but i think my cat5 lead is suspect

Im curious
So both hmi's integrated in your Step7 - and in netpro?

Hi...Yes
I the project I have 2 CPU's, 4 HMIs and 2 servos on profibus

Each CPU has its own Profibus network (Profi1 and Profi2) and each network is a PLC,2 HMIs and a servo

Profi 2 works 100% ok

Difference between them is that all profibus address are unique because customer wants to integrate the 2 systems later but we we designing it as 2 seperate systems so originally I had the profi networks identical

PLC (2),,HMI(3),,HMI(4)..SERVO(5) <-- original profi 1 & 2 now just Profi1

PLC(6)..HMI(7)..HMI(8)..SERVO(9) <--- new profi 2

Also ... My WinCC always shows GERMAN text on startup in the "WinCC is starting" dialod from within Simatic manager but I can live with that but I am wondering about corruption somewhere

Hi
Further to this I went to work today and found my USB Profibus adaptor would not work AT ALL with anything so I suspect my issues were done to that. I will have a new shiney one tommorow to retry

If you put 4 HMIs on one profibus network it will slow that network significantly because profibus uses token passing between masters and a master con only communicate with its slaves when in possesion of the token. So if you have 4 HMIs and 2 CPUs on one network there will be 6 masters!

My advice would be: 1) use Ethernet instead 2) put the HMIs on a separate network.

Good luck with your anomally.

Nick

Hi I have 2 independant networks of 1 plc and 2 hmi each plus a servo drive.

The customer wants to integrate and have their own controls people so i will let them decide on that themselves

They asked for Profibus specifically

+1 what Manglemender said.

Oh, in addition to slowing down the system, it also becomes much more inflexible. Think about that with many CPUs and HMIS in the same system, it is quite plausible that you will need to reconfigure, replace, shutdown for maintenance etc., which will affect the system if it is running 24/7. Sometimes you cannot get to reconfigure it because if this. Another reason for separating the higher level "bus" with the lower level fieldbus. Also do not physically wire individual logical fieldbusses together, thats what DP/DP couplers are for.

Customers sometimes are less qualified incertain technical aspects than they think themselves. Be sure to officially explain to them the consequences if they ho ahead with their own ideas. Customers also sometimes have strange ideas about who is responsible when it goes wrong. Since they explained how they want to do it, and if you do not protest, then you become part responsible. Just saying.

+1 What Jesper said.

In my experience, custometrs often need to be "Educated" and they WILL call you when it doesn't work.

My other favourite is "we want you to use these blocks that we've written" which are, almost invariably, appalingly badly written. The phrase "why have a dog and bark yourself?" comes to mind.

Nick

Oh another good one.
If everything is hooked together in one big Profibus system, one error can bring everything down.

And yet another one.
If the big system is down, with everything connected together it becomes MUCH MUCH harder to pinpoint the error.

Big profibus systems --> Set aside the expense for and buy a Profibus analyser for the day when you are going to need it.

Hi All
We have already expressed concerns officially and had to do design and document changes to get to Profibus

Cheers for your points. PS It is all working fine with the new adaptor

It still makes no sense that you download to hmi address 4 and hmi 3 recieves the configuration
Anyway- Im glad its working