communication btw PLC and server

[PSpal]

we have the sytem in which a lot of PLC 5/80E, 5/40E,SLC 5/05 etc are connected thru ethernet to HP-alpha server. Now the server has been updated but we are facing some problem in communication. It is told that old communication is in 'half duplex" mode but the new server support "full duplex" . What is "half duplex"/full duplex" in Ethernet?! the same for Serial communication is clear but what it mean in ethernet? can anyone clearify..pls..

 

[harryting]

http://en.wikipedia.org/wiki/Duplex_(telecommunications)

It's the same context no matter the communication protocol. Keep in mind, in your system, the PLCs might still be limited to half-duplex because that's what their ethernet card can support.

 

[Ken Roach]

Half Duplex and Full Duplex mean the same things in Ethernet as they do in Serial.

http://en.wikipedia.org/wiki/10baset

Older PLC-5E controllers support an AUI interface and 10 Mb/s Half-Duplex Ethernet. The AUI transceiver is responsible for converting to 10Base-T, 10Base-2, 10Base-5, or fiber optics.

Older SLC-5/05 controllers have a 10Base-T plug built in.

By "Older", I mean "From the early 1990s until about 2004".

PLC-5E controllers after Series F have a built-in 100Base-TX connector (the conventional Ethernet 8-pin "RJ45" style) and SLC-5/05 controllers with Series C hardware also support modern 100Base-TX Ethernet. These are easily distinguished by the presence of the text "10/100 MB" next to the Ethernet port instead of the letters "ENET".

If you have older half-duplex equipment, it is up to your and your IT department to properly configure your new switches to accommodate the older fixed-speed half-duplex hardware.

Most modern Ethernet switches perform Auto-Negotiation, and will properly fail auto-negotiation with a 10 MB/s Half-Duplex device. Some switches, however, continue to send Auto-Negotiation packets that can interrupt communications, and therefore must be manually set to 10 Mb/s Half-Duplex.

 

[PSpal]

Thanks for the quick reply..What I figure out that there is no selection/setting to make it full duplex from half duplex.

Details of processor is as below.
the PLc 5/40e , 5/80 e are connected to ethernet thru. D link..

The versions are-5/80E- series E /revision B...5/40E- series c..revision e. &
for slc 5/05. os 501. os series a ;frn- 3,processor catalog no-552,series -a, frn-1.
Can u confirm whether these are capable for full duplex? if not. what is the series/version required to be uploaded. ? can it be done thru software or replacement is required (for updation)

 

[Ken Roach]

For the PLC-5 and SLC-5/05 controllers, the upgrade to 100Base-T Ethernet is a hardware difference; there is no field upgrade possible.

All of the controllers you listed have 10 Mb/Half-Duplex Ethernet ports.

To support 100Base-TX Ethernet, PLC-5E controllers must be Series F. SLC-5/05 controllers must be hardware Series C.

My recommendation is to get a commercial or industrial grade Ethernet switch that at least allows the speed and duplex configuration of the ports.

 

[iant]

Hi Ken,
I have had my first experience with new industrial Hubs - Best Option
I used an old router of mine for testing - Worked But Not Well.

I totally support your recommendation

 

[Tify]

Hello, guys!

but i have a question that how could a Ethernet Card linked to PLc send message to my dell servers, i am a new guy

 

[iant]

Use OPC server software
Sorry Tify - more information or maybe a different post is needed

 

[PSpal]

thanks Ken..for urs support.. Our IT dept just do the same...& the system is running ok..I just doubting one thing...whether this can lead to msg loss!!(using a switch to connect half duplex PLc with full duplex server)..because then it can became a major issue. and secondly whether full duplex (instead of half duplex) can increase 'production" ..in any way?

 

[lee1968nh]

You'll find no OPC server for that devixce if its talking to a CP3400 or CP3500. Is it talking or do you plan to use the NASY interface card? If so, it is RS422...and uses a proprietary protocol...it doesn't operate like typical protocols either. The guy(s) who wrote the code for that would be long retired or dead. However, I have written a driver for Citect for the replacement of those CP315 operator interfaces that uses the NASY card. If you need, I can help.

 

[iant]

hi Lee
The OPC server comment was to "Tify"
and is unrelated to this post
I was suggesting he/She create a new post
as there were no details as to what PLC was being used