PanelView Plus Comms

[Jiri Toman]

Jiri: The DB9 port on the 5/04 can be set to DH485 OR DF1, I am quite sure.

Believe me I know the difference between DF1 and DH-485 only too well.
Yes you can run DH-485 point to point on Chan 0 (RS-232) but
you can't network it unless you convert RS-232 to RS-485. That's why you need AIC+.

 

[Tom Jenkins]

Thanks for the clues, guys.

Ken, the job is in southeastern Idaho, 180 miles due north of Salt Lake City. I am no longer on site, and since the DH+ wiring was not part of our scope I didn't check the wiring details myself. The system integrator is very competent, and I'm requesting that he check into the wiring and termiantion issues. The network to the other buildings is about 200 yards long through ductbank.

The
PV+ is on DH+. We set up our slave PLC to master PLC link as DH-485 so this kind of issue won't screw up our control. We are using AIC+ modules on all DH-485 links. I meant to say that changing the PV+ from DH+ to the DH-485 network isn't a viable solution because it would crash that link.

The PV+ data is in 16 contiguous files, but changing that probably won't help because the PV+ would just hammer the single file.

I don't think wiring is the issure, because the network appears to work fine with the PLC online but the PV+ disconnected. I'm foing to get verification of this. Here is what the system integrator wrote: "Upon connecting the Blower PLC and PanelviewPlus HMI to the DH+ netowork, the network crashed.
Disconnected the Panelview and the network was fine."

We are considering putting and ethernet card in the SLC, and connecting the PV+ to it. The downside is there is a lot of data, and I think block transfers will be required to move it back and forth to the SLC 5/04.

Keep the ideas coming - this is the kind of help I was hoping for.

 

[akreel]

We are considering putting and ethernet card in the SLC, and connecting the PV+ to it. The downside is there is a lot of data, and I think block transfers will be required to move it back and forth to the SLC 5/04.

"Block Transfers" - Is there a dirtier word in the SLC lexicon? Not from what I've seen and heard.

If you have to resort to that, call me. I still have the program for that indexing table project. There are block transfers and lots of creative data packing in there. I might be able to save you some development time.

AK

 

[Tom Jenkins]

If you have to resort to that, call me. I still have the program for that indexing table project. There are block transfers and lots of creative data packing in there. I might be able to save you some development time.AK

Thanks, Aaron - if I can't avoid that, I'll call you.

 

[93lt1]

Tom, It looks like the PV+ line has it out for you!

I think I would try to get the Panelview Plus powered up, shutdown the application, connect the DH+ cable, and then see what happens.

If I remember correctly, the DH+/DH-485 card should still be active, but there should be no data traffic.

Not a solution to the problem but it might help...

 

[scooby blue]

We are considering putting and ethernet card in the SLC, and connecting the PV+ to it. The downside is there is a lot of data, and I think block transfers will be required to move it back and forth to the SLC 5/04.

Keep the ideas coming - this is the kind of help I was hoping for. [/B]

Did AB figure out a way to add an ethernet module to a slc? Or was this a type O?

 

[Tom Jenkins]

93: Good troubleshooting idea - I'll pass it on to the guys on site.

Scooby: The ethernet card would be a Pro-Soft unit that goes into the SLC rack. I don't think A-B itself has a card that would do the trick. That's what would lead to all of the nasty block transfers.

 

[93lt1]

Off topic question:

Will the Pro-Soft module allow upload/download?

 

[scooby blue]

cool we used a 3rd party high density analog input module years ago. I think that it was made by prosoft also.

 

[[email protected]]

Idaho Project Panelview + and DH+ comm

Hello, I am the systems integrator on this project. This is the first time I have used this message board and I am very pleased with the amount of ideas and knowledge available, and thank you very much for all your comments.

The system DH+ architecture contains (8) SLC/5/04's including the blower PLC, (1) Panelview +, (1) RSView 7.00 SCADA Node, (1) RSView 32 7.00 Works Development Node.

The DH+ network has been verified that it is NOT a star configuration, that it is a daisy chain network, and there are termination resistors at each end.

When the Blue and Clear wires on the PV+ are backwards as described above the DH+ network crashes completely, every PLC in the RSWho window gets a red X.

When the Blower PLC and PV+ is wired properly into the DH+ network, the DH+ connections in the RSWho window will frequently show a red X, come and go, not always the same PLC and always one or more PLC's with a red X. RSView32 crashes and locks up completely, no screen display of any data points.

At this point we have to bypass the PV+, close the RSView32 SCADA project and restart in order for RSView32 communication to work again.

Maybe this inforamtion will stir up some more ideas.

Thanks

 

[Ken Roach]

You say that the PV+ has the update rate on the screens "turned down as far as possible". What's that rate ?

Are there any trends in the PV+ project ? What rate are they running at ?

Have you attached the PV+ when it is in Configuration Mode ? It does not initiate any traffic on the network in that mode. If it still causes the network to fail when it's in Configuration Mode, then replace the 2711P-RN6 board.

DH+ is good for about 10,000 cable-feet at 57.6 kb/s, but only for about 2,500 cable-feet at 230.4 kb/s.

We know there is about 600 feet of ductbank between buildings; is the DH+ running parallel to high voltages in that duct ?

A scope trace will tell you a lot about whether you have a network or a PanelView problem.

I have a scope and a DH+ analyzer but I seldom have to use them !

 

[Jiri Toman]

Now it looks like a noise

From what you have described I have a feeling that you have noise introduced into the DH+ cable. About a year ago I had a similar problem, a C-net network had several 1756-CNET modules showing intermittent operation, module green light in the RSLinx would go On and Off. I started tracing out the ControlNet cable and found out that they have routed the cable very close to a large Mitsubishi AC drive. Once I moved the cable away from the drive the problem disappeared. I suggest that you examine your cable installation and re-route if necessary. In terms of the total length of your cable,
I can only assure you that DH+ will work reliably over 10000 Ft
at 56.7kB. I have one installation that approaches the 10000 Ft and
it works like a charm. One more thing. As the length of the cable gets larger you need to drop the termination resistors down to
75 Ohms. I had to do that on the 10000 Foot installation to get it working.

 

[akreel]

I've got to agree with Jiri and Ken. I don't think your network topology is wrong. There has to be some other factor, like noise, line loss, wiring, or faulty hardware. The red X's floating across nodes would indicate to me that you have intermittent communication. Your network isn't DOA, but it's suffering badly. The good news is, you should be able to fix it without adding extra PLC cards.

You shouldn't be over taxing the network, either. I've seen at least 7 SLCs, 7 Panelviews, and 2 RSView32 stations connected to DH+. Traffic was slow, but it got through.

AK

 

[hilgs]

more details

Ken, in response to your questions.......

We have 11 tags in 1 data log madel that are updated every 30 seconds. These 11 tags each represent a different trend in the project (6 Blower trends and 5 Tank trends). There is only 1 pen per trend and only 1 trend per page.

When I was on-site, late summer, I changed the "Maximum Tag Update Rate" from 1 to 30 seconds on each page. I saw very little difference in netwrok performance as I varied the rate. Presently, the Update Rate is set at 5 seconds for all pages in the project.

A-B likes to preach about the need to have at least 6 feet of cable between devices. If the cable between the PV+ and the SLC 5/04 in our panel is less than 6 feet in lenght, could we be getting some reflections in the signal?? Just graspong at straws, but I'll throw that out there.....

 

[[email protected]]

Idaho Project PV+

The PV+ and Blower PLC are in the same panel, the DH+ cabling enters and exits this same panel.

When bypassing the PV+ on the DH+ network we simply remove one jumper between the Blower PLC and the PV+ and connect the exiting DH+ leg to the Blower PLC DH+.

If it was noise somewhere else in the duct bank, then why would the problem only exist when the PV+ is connected.