Building a PLC Network

[robw53]

I am looking into setting up a plant wide network so ive been searching the net for examples but i crnt seam to find any PLC setups, i found some typical PC networks but dont know if these are transferable to a PLC network and as its been designed from the ground up i want to make sure i spec it up just how i want it.

ive got about 5 locations inside the factory where i would put a switch, the server would reside in the engineering office and in the future would run a scada system and historian etc

so if anyone has any tips or docs any links would be appreciated

Rob

 

[Lancie1]

For a PLC network (PLCs communicating with each other, not just back to a remote PC server), you first need to find out what brands and models of PLC that you have, then look at the specs for all those PLCS to find out if there is a common communications protocol that can be used for all of them.

 

[The Plc Kid]

I have a very large automation network and we do it so that each major line is it's own network with all the drives, plcs, hmi, switch are in that network then we have a layer 3 switch at each line that connects back to a core switch in the automation network datacenter which is just a large office with switch and server racks.

Our enginering computers and laptops for the automation network can connect to any major line this way and drill down to the component via vlans and routing.

There is also a DMZ when items like data collection and historians sit and are shared with the corporate network.

 

[The Plc Kid]

Here is a link that will also be helpful to you Rob.

http://literature.rockwellautomation.com/idc/groups/literature/documents/td/enet-td001_-en-p.pdf

 

[PeterMalt]

In my plant we have a industrial network from Hirschmann Belden .
The MICE series with Modular Rail .
The main backbone is glasfiber with hyperring. The main switch monitors the connections and if the ring is cut some where the communication runs over the othter side.

 

[The Plc Kid]

Rob

Also if possible I would highly recommend you make you connections with fiber. Doing this means you don't have to worry about the noise and distance issues / limitations of cat 5 or cat 6 cable.

 

[robw53]

thats definitely some serious bedtime reading!

sorry i lacked in upfront information, the network is more for been able to collect data and do online mods etc then to have the PLC's talking to each other, where plcs are talking to each other they already have CAT5 between them.

i was after something like 4/5 16 port managed switchs one in each area/section of the factory configured in a ring then from each managed switch, a star configuration out to each panels dumb switch
very much like what is on page 296 of the PDF.

each switch will probably hook upto maybe 6-8 PLCs each so its not going to be a huge network

also the server could go in the ring as it will be located between two proposed switch locations.

i will start to read through the manual maybe it will clear some things up for me

Rob

 

[nightline]

thats definitely some serious bedtime reading!

sorry i lacked in upfront information, the network is more for been able to collect data and do online mods etc then to have the PLC's talking to each other, where plcs are talking to each other they already have CAT5 between them.

i was after something like 4/5 16 port managed switchs one in each area/section of the factory configured in a ring then from each managed switch, a star configuration out to each panels dumb switch
very much like what is on page 296 of the PDF.

each switch will probably hook upto maybe 6-8 PLCs each so its not going to be a huge network

also the server could go in the ring as it will be located between two proposed switch locations.

i will start to read through the manual maybe it will clear some things up for me

Rob

Be prepaired for the future, and install glasfiber the first time. Beleave me, you have to do you're job twice if you install coper wire the first time!

Jack

 

[Stephen Luft]

Rob,

Regarding your network, much will depend on the controllers and what they have availble for communications. The easiest would be an Ethernet connection.

The challenge with Ethernet is the 100 meter communications limit. You can overcome this obstacle with extenders for which we offer Westermo's DDW-120

http://www.eternity-sales.com/westermo/wolverine_shdsl_ethernet.htm

Going into an Ethernet switch such as the L110-F2G, which is a layer 2 switch.

Server software for managing your industrial network can be done through Kepware's KepserverEX:

http://www.eternity-sales.com/Kepware/Kepware.htm

For which they offer an extensive library of communications drivers and also offer an SNMP product for managing your industrial network:

http://www.eternity-sales.com/Kepware/snmp.htm

Another option, if you are looking to avoid wires is going wireless.

For that we have two options:

Westermo's RM90 or RM240

http://www.eternity-sales.com/Westermo/Industrialwireless.htm

or if your controllers have serial communications,

http://www.eternity-sales.com/WirefreeCNC/hardware.htm

for which you will require wireless access points.

So, there are a few options regarding setting up your network and how it can be managed.

Wired or wireless?

 

[The Plc Kid]

Rob,

Regarding your network, much will depend on the controllers and what they have availble for communications. The easiest would be an Ethernet connection.

The challenge with Ethernet is the 100 meter communications limit. You can overcome this obstacle with extenders for which we offer Westermo's DDW-120

http://www.eternity-sales.com/westermo/wolverine_shdsl_ethernet.htm

Going into an Ethernet switch such as the L110-F2G, which is a layer 2 switch.

Server software for managing your industrial network can be done through Kepware's KepserverEX:

http://www.eternity-sales.com/Kepware/Kepware.htm

For which they offer an extensive library of communications drivers and also offer an SNMP product for managing your industrial network:

http://www.eternity-sales.com/Kepware/snmp.htm

Another option, if you are looking to avoid wires is going wireless.

For that we have two options:

Westermo's RM90 or RM240

http://www.eternity-sales.com/Westermo/Industrialwireless.htm

or if your controllers have serial communications,

http://www.eternity-sales.com/WirefreeCNC/hardware.htm

for which you will require wireless access points.

So, there are a few options regarding setting up your network and how it can be managed.

Wired or wireless?

Sell, Sell, Sell

 

[robw53]

Yes it's going to be Ethernet most PLC's are compactlogix, SLC 50/5 and micrologix 1500 w/net-eni and all have PV+'s, Flex I/O etc

If I do it as I was thinking with a ring setup then the distance between each switch would be less than 100m but I think I will be going with fibre if the price isn't stupidly ridiculous


Rob

 

[The Plc Kid]

Just my opinion here Rob but I would stay away from ring for your network topology for making a plant network.

It works great to connect all machines and plc's and drives on a common line but most of the gear to support true fast ethernet ring like you are thinking of is proprietary hardware like rockwells stuff or Hirschman and Moxa.

You may want to do more with this network as time goes on and at some point may even want to share data to corporate IT.

I would stick to standard star topology for this and do rigs at each major line or equipment if you wish.

The other advice I will give is stick with cisco switch's if budget permits.

Are you planning any wireless on this also? If so you may want to make the wirelessa seperate VLAN.

 

[nightline]

The other advice I will give is stick with cisco switch's if budget permits.

Tip: A-B switches are brand labled Cisco switches.

Jack

 

[The Plc Kid]

Tip: A-B switches are brand labled Cisco switches.

Jack

I was speaking primarily of his core switch which would be more port dense than anything rockwell sells.

Also just for correction as far as AB switch's only the stratix 8k series and the new 5700 series is a cisco switch the 2000 and 6000 series are not.

 

[robw53]

Ok I will go with your suggestion of STAR only reason I wanted ring was it makes it so much easy with how the workshop is to the rest of the plant