Ethernet switch selection, newbie questions.

[Elcan]

Hi,
I need to connect 3 CompactLogix PLCs and 3 touch screens, and have remote access to them from a PC.
I guess that I will need an 8 port ethernet switch, but maybe there's another configuration that you experienced guys want to suggest.
Besides, I would like to hear your suggestions on what type and brand to use. I've read a thread with a discussion about industrial/not-industrial switches, and the "managed" and "unmanaged" concepts.

I will appreciate your comments.
Thank you!

 

[fuzzy logic]

Elcan, you may use an unmanaged switch (industrial) to connect your devices.

Managed obviously works as well, but i think in your configuration is not needed.

You may use the new Rockwell Ethernet/IP Switches Stratix 2000 (cat n. 1783-US08T)

- [font=comic sans ms,sans-serif]fuzzy logic[/font]

 

[widelto]

Elcan:

I have severral N-tron switches in our plant, for your requirements the best option is the 508TX model, they have a good web page with a lot of info, do not know if the´re cheaper than stratix from rockwell.

 

[Keystone]

I use Hirschmann "Spider" series, they have 5 & 8 port, 24VDC and DIN Rail mount. I have about a dozen in the plant with no problems.

 

[nonuke]

We use Phoenix unmanaged industrial switches SFN 8TX 24VDC for DIN Rail with the cost of aprox. $90 with no problems.

 

[dmroeder]

We use Phoenix unmanaged industrial switches SFN 8TX 24VDC for DIN Rail with the cost of aprox. $90 with no problems.

We use these too.

 

[Chris S]

We use the hirshmen spiders aswell as the Managed Hirshmen's for our data collection and keeing the CIP messages off the main network.

Basically it works like this put the spider on one system and to link 2 systems together use a managed switch and get someone to show you how to turn off the CIP message throughput for the switch. Not sure the technical name for it but it keep down the messages that dont have a specific dest so your traffic to other networks wont be hindered by the Controllogix network.

Basically to sum up my increadaly incoherent thoughts today. Use Hubs (unmanaged switch's) unless your going onto a data collection or a plant network. Then worry about managed switch's.

Oh yea and use industrial switches. About a year from now when the store bought HUB's go down you'll be ****ed.

 

[diat150]

we use sixnet and phoenix style switches. its nice to have din rail switches that have the ethernet plugs on the fron as opposed to the side, as it is much easier to plug into.

 

[bkottaras]

I use Hirschmann "Spider" series, they have 5 & 8 port, 24VDC and DIN Rail mount. I have about a dozen in the plant with no problems.

I second the Spiders. Never had a failure.
Also, MOXA makes din rail mountable industrial switches (unmanaged, 5 port,for about 90 bucks)
They also make the 8 port and 16 port, same configuration, din rail mountable.
We have switched to MOXA for over a year and have had no issues whatsoever.

 

[KP_EENG]

I have a line running a GE RX3i with 3 Red Lion touchscreens and I used a Moxa 5 port managed switch to connect them. To date, I have not had any problems with the system, but I have other systems that have an AB SLC 5/05 with an AB Ethernet Panelview connected with an unmanaged switch and anytime that I try to program across the switch, the Panelview drops out with a communications loss. I would go with a managed switch just to avoid any issues.

Best regards

 

[rdrast]

Basically to sum up my increadaly incoherent thoughts today. Use Hubs (unmanaged switch's) unless your going onto a data collection or a plant network. Then worry about managed switch's.

Just a quick correction to otherwise excellent information... A switch and a hub are NOT the same thing, and unless you have a specific reason for it (and KNOW the reason) there is no point ever using a hub.

A Hub is essentially just 'All Ports In Parallel'. No smarts, no isolation. A Switch on the other hand (even unmanaged) is a smart device that creates a virtual hard-wired path between communications partners. It does not just retransmit everything on every port to every other. Switches can also provide speed and duplex modifications (A Single switch might have 10Base, 100Base, and 1000Base plugged into it, and all can talk... A hub is single speed only).

 

[Chris S]

yes sorry you are correct. Only use switch's I screwed up the terminalogy. I am used to talking to maint techs who usually dont know the difference between a switch and a hub.