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View Full Version : SLC 5/05 to Danfoss VLT over Ethernet


jedft
December 14th, 2006, 01:16 PM
Hello all,

I am trying to talk to two Danfoss VLT 8000's over ethernet using the Danfoss "Ethernet Master" module. Has anyone else used one of these ethernet master modules (part# 175N2584)? Were you able to create the "FC protocol telegrams" using RSLogix 500? I don't want to get too in depth with the first post here if no one has used one.

Thanks,

Jed

jedft
December 15th, 2006, 10:14 AM
Ok, so since no one has apparently used this Danfoss "Ethernet Master" module, does anyone know where there may be some sample code using EEM or MSG functions with a SLC 5/05 to talk to anything over a generic ethernet to serial converter? This would get me pointed in the right direction anyway. I cannot figure out from the documentation provided by Danfoss exactly how I need to construct the data file in the PLC.

JSR WhineyVent:3

It's always difficult for me to develop a program for equipment that won't be here for months and I won't be able to test until 2 days before it needs to ship out. I guess my main problem here is I have never used ethernet before, it's always been hardwired I/O. This Ethernet to serial conversion problem is not making it easy to learn.

By the way, before anyone asks why I used a SLC 5/05.... spec'd, as was Danfoss VFD. And of course I have no experience with either. Our "internal" spec, or company policy if you will, is to use Ethernet whenever possible. Since Danfoss produced the data sheet for this ethernet master, I am now expected to make it work. Unless I can develop a very convincing argument otherwise I'm stuck. This is hard to do without having the equipment to show them (and me) it will or won't work. But we can eliminate some I/O modules if we use this magic little box and Ethernet! Cha-ching!

(END)

hipoint2
December 15th, 2006, 01:07 PM
Well I will tell you alittle that I know about both of them. I had a similar application as you, but mine involved Danfoss' 2800 series book style drives and a SLC 5/05. I installed 80 of these drives originally using a SLC 5/04 and a basic module to talk the "FC" Danfoss protocol to all of the drives on the "FC" network. It was alittle time consuming, but I finally got it figured out and the ladder was quit amazing, but needless to say I got it working and the nice thing about it is they are all on one network with some repeaters in their. So my next project was to add 150 MORE drives. So after looking at all my options Danfoss came to us and said that they have this ethernet BOX that will work with a ethernet network. So after looking into it it came out that a AB SLC5/05 will not talk true ethernet/IP. They wanted me to upgrade to the logix processors that talk true CIP instructions or something like that. Well that was totally out of the question so we scraped all of that and went to a Modbus network with Yaskawa drives. Hope that answers some of your questions.

jedft
December 15th, 2006, 01:40 PM
"So after looking into it it came out that a AB SLC5/05 will not talk true ethernet/IP. They wanted me to upgrade to the logix processors that talk true CIP instructions or something like that."

That could very well be my answer right there. I will look into the SLC and CIP stuff. Since all this stuff was spec'd by the customer (evertyhing EXCEPT Ethernet) I can probably convice sales just go back to hardwire.

As the wise Homer Simpson once said: "Weaseling out of things is important to learn. It's what separates us from the animals ... except the weasel."

Thank you!

Ken Roach
December 15th, 2006, 06:52 PM
Wow, there seem to be a lot of threads lately with confusion about the SLC-5/05's Ethernet capabilities, or about the interoperability of Ethernet-based automation protocols in general.

FACT: The SLC-5/05 isn't meant to run Ethernet I/O.

I haven't worked witht this Danfoss device, since I compete directly with Danfoss. The pictures I've found with Google make it look a lot like an HMS Fieldbus serial gateway.

Can you provide a part number or link ?

jedft
December 18th, 2006, 08:02 AM
"Can you provide a part number or link ?"

Ken, I attached the data sheet they sent me. I had to delete the title page to get the file to fit.


"Wow, there seem to be a lot of threads lately with confusion about the SLC-5/05's Ethernet capabilities, or about the interoperability of Ethernet-based automation protocols in general."

My guess is that people (specifying engineers) are starting to trust ethernet enough to use it in more applications but don't know enough about it to know what works and what doesn't and why. In our area of business (water/wastewater) ethernet is still fairly newfangled technology, at least in our neck of the woods. Hence, we get people stuck on old PLC platforms wanting new capabilities. They don't want to change to new PLC's or drives that seamlessly support the new technology.

"FACT: The SLC-5/05 isn't meant to run Ethernet I/O."

So what enables a PLC (or anything for that matter) to "run" Ethernet I/O? What should I be looking for in a spec sheet that will tell me it will work?

Ken Roach
December 18th, 2006, 02:01 PM
Let's not get into the big industrial Ethernet discussion; that's for another thread. In this case, what you have is a misapplication that you need to sort out.

As I have mentioned repeatedly in other threads, the SLC-5/05 does have some limited EtherNet/IP messaging capability. What it doesn't have is the "I/O Scanner" function that the ControlLogix family of controllers have.

Even if these were A-B drives, I would not be recommending using the Ethernet port of the SLC-5/05 to control them. It just is not safe or prudent to use a messaging port for I/O functions.

What makes this even less prudent are the risks to your schedule and system reliability. Setting out to use a new and uncommon product with neither time nor bench-testing is a risky thing for anyone.

If it were me, I'd stick with a network technology that is supported by both products; DeviceNet or Modbus. Because there are only two drives, you're not saving a whole lot of I/O modules anyhow.

Ken Roach
December 18th, 2006, 02:25 PM
All of that being said, there's a possibility you could make such a system work. The SLC-5/05 firmware revision 10 has an "EtherNet/IP Explicit Message" instruction that will let you read and write to the Assembly objects inside the Danfoss gateway.


http://www.plctalk.net/qanda/uploads/EEM_Danfoss.GIF

I'm not guaranteeing that this will work. I still recommend a more stable and less risky approach. You're on your own for support from both manufacturers.

jedft
December 18th, 2006, 02:36 PM
"I'm not guaranteeing that this will work. I still recommend a more stable and less risky approach."

Trust me, this was not my idea. I'm all about hardwired I/O to the drives, or more supported communications... but with 2 drives, what's the point? :shoot:

"You're on your own for support from both manufacturers."

You can say that again!

Thanks Ken

jedft
May 24th, 2007, 10:36 AM
OK, this job has become a reality and I am in the thick of it. I am using the EEM instructions as Ken showed above. I have 2 instructions, 1 write and 1 read. The write is working perfectly. The read is not working at all. I am getting an error code of d9 (Reply not recieved before user-specified timeout). Occasionally, I will also get a d8 error (Connection was broken) I cannot find where I can specify a timeout value even though it says it's "user defined". I have the write EEM running continuously. I have tried putting the read on a timer and experimented with different times, as well as trying to continuously run the read EEM. When I set the continuous run bit the error goes away, but I still don't get any data. As far as I can tell I have everything else (IP address, class, instance, attribute) set up correctly. I am using the same data file for both instructions, though I don't think that matters. The read's control is N12:0 and I have 36 words going to N12:101-N12:36. The write's control is N12:142 with 36 words coming from N12:201-N12:236. Nothing else is writing/reading to file N12. Any ideas? Need more info?

Tonk
May 24th, 2007, 11:11 AM
I had to set up a Danfoss to communicat with a Siemens S7-315 plc used profibus. Siemens side was easy the Danfoss was nothing but troublesome. Got it to work and worked well. Can you use a profibus module and do your communication that way. Not sure if AB sell such a module but it might be an easier alternative.

Ken Roach
May 24th, 2007, 11:31 AM
Take a step back, take a deep breath.

Don't use the Continuous Run bit, don't auto-retrigger the message. Just experiment with a manual trigger or a slow timer on the Read command first.

Right now it sounds like the drive and SLC-5/05 can't communicate with one another at all over Ethernet. So post the IP address configurations you have entered for each device. From a computer on the network, PING each device, then type "ARP -a" and post the results.

Post the actual EEM parameters you are using in the message.

Send me an IM or e-mail if you don't want to wait to do this via Forum.

jedft
May 24th, 2007, 12:24 PM
OK, there are 4 devices on the network.
192.168.0.1 - SLC 5/05 1747-L551C Series C FRM 10 and later
192.168.0.2 - PanelView + 1000
192.168.0.3 - Danfoss Ethernet Master module (connected to 2 drives via serial RS-485 network using Danfoss FC protocol and to SLC 5/05 via Ethernet/IP)
192.168.0.100 - My computer

A ping of each came back identical for all 3:
(Packets: Sent=4, REceived = 4, Lost = 0
Round trip:
Min = 0ms, Max = 0ms, AV. = 0ms)

Arp -a produced this:

Interface: 192.168.0.100 --- 0x2
Internet Address Physical Address Type
192.168.0.1 00-00-bc-35-72-2a Dynamic
192.168.0.2 00-00-bc-b0-67-1a Dynamic
192.168.0.3 00-30-11-02-a1-52 Dynamic


My EEM setup screens look identical to the one you posted above except for the addressing. The only difference between the read EEM and the write EEM is the Instance which is 64h for read and 96h for write per the Danfoss Ethernet Master manual.

mgvol
May 24th, 2007, 12:34 PM
The MSG timeout and MSG reply timeout is set in the Channel Configuration > Channel 1 System tab, on the right hand side of the Protocol Control settings. Default values are: MSG timeout 15000 (X1 mS) and MSG resply timeout 300 (X1 mS).

jedft
May 24th, 2007, 12:37 PM
I slowed down the Message Reply Timeout to the max and now the error I get every time the EEM runs is d8 - "Connection was broken" So does that mean the real problem is I am never even connecting to the Danfoss module? If so, why would the write work but not the read?

Ken Roach
May 24th, 2007, 06:11 PM
Let's slow things down a little further to examine.

Try disabling the Write message. Does the Read message function when only it is running ?

I usually alternate my Read and Write messages, generally triggering the Read from a repeating timer, then triggering the Write from the /DN bit of the Read.

Post a link to the Danfoss Ethernet Master user manual if you can. If you can post your SLC-500 code, or a snippet of it, that would also be helpful.

If you have a managed Ethernet switch that allows you to do "port mirroring" you could run Ethereal/Wireshark on a port that mirror's the SLC-5/05's traffic, and that would give you a low-level look at the Ethernet protocols that are being exchanged. I also keep a 10/100 Mb/s hub around so that I can install Ethereal as a passive sniffer (with a PCMCIA 10/100 Ethernet interface to my PC that has no protocols bound to it).

Norml
May 24th, 2007, 06:25 PM
Well I will tell you alittle that I know about both of them. I had a similar application as you, but mine involved Danfoss' 2800 series book style drives and a SLC 5/05. I installed 80 of these drives originally using a SLC 5/04 and a basic module to talk the "FC" Danfoss protocol to all of the drives on the "FC" network. It was alittle time consuming, but I finally got it figured out and the ladder was quit amazing, but needless to say I got it working and the nice thing about it is they are all on one network with some repeaters in their. So my next project was to add 150 MORE drives. So after looking at all my options Danfoss came to us and said that they have this ethernet BOX that will work with a ethernet network. So after looking into it it came out that a AB SLC5/05 will not talk true ethernet/IP. They wanted me to upgrade to the logix processors that talk true CIP instructions or something like that. Well that was totally out of the question so we scraped all of that and went to a Modbus network with Yaskawa drives. Hope that answers some of your questions.

I've seen the same thing happen with trying to setup a slc 5/05
with Toshiba drives. The Toshiba drive supports a ETH-200 Ethernet/IP module which seems to work with anything but the SLC. This problem actually got out in the field and some enterprising person put a Micrologix in as a middle man to convert to Modbus. I still don't quite understand how it got working.

jedft
May 25th, 2007, 07:16 AM
Well, I disabled the write, and the read still does not work. I even deleted the rung with the write.. same thing. Upon further reading it looks like the module, once sent a write command, responds with the status data. If that is the case, I would need an instruction that writes and then reads in one operation.

As usual, time contraints are going to be the decided factor here. The write message is working reliably so I am going to bring a VFD fault contact and VFD speed 4-20 into the PLC and be done with it. That's all the info I was using from the read anyway, really. I suppose the real answer here is don't try to use a SLC with something like this. I wouldn't have except the SLC was spec'd. It just isn't designed for it. Had I been using RSLogix 5000 and a compatible PLC I would have been done 2 days ago.


I really appreciate the help.... off to do some wiring.