Tobi

We currently have all SLC 5/05 with a few MicroLogix 1100 and 1400 all are connect to an Ethernet network and our SCADA software is RSView32. We are currently in the planning stage of adding a new plant process and I am thinking this would be a good time to start migrating away from the SLC and to one of the Logix PLCs. In most cases we have one PLC for every major machine or process, so there will not be large amounts of I/O for any one PLC. The entire plant process is a wastewater treatment plant so there is not a need for any advance functionality. The SLCs have been more than adequate for everything we have ever needed to do. We do have about seven CompactLogix at a separate water treatment plant and have been satisfied with them so far. Our consultant has recommend the ContolLogix but from what I have read and seen this will be overkill for what wee need to do. It appears the CompactLogix are a little bit cheaper than the SLCs and quite a bit cheaper than the ControlLogix. I know there is some benefits to the ControlLogix platform like the ability to hot swap I/O but really in our process this is not critical. I like to try and look at this as if this was my money what would I spend it on, since ultimately this is public money. Any thoughts or suggestions about the advantages or disadvantages of either would be appreciated.

I have four MSG instructions in my logic that are being used to read Modbus registers from two sepreate Flygt MAS 711 relays (pump protection relays). Channel 0 is set to Modbus Master and everything works fine as far as reading the Modbus registers. My problem comes when I want to disable one or more of the MSG instructions. I want to be able to disable the MSG instructions, if say one of the pumps are out of service, in order to keep the MSG from timming out. I used a counter to sequence the four MSGs so that when MSG 1 was done or errored it would increase the counter and move on to MSG 2 and so on until MSG 4 finished or errored and then it would reset the counter and start over, when all 4 MSGs are enabled everything works fine. If I disable MSG 1 or MSG 4 everything works fine, however if I disable MSG 2 or 3 the counter stops when it gets to the diabled MSG. I am not sure why this does not work, maybe I am overlooking something simple or maybe I just don't fully understand how the logic is being solved, but any pointers or help on this would greatly be appreciated. I have attached a copy of my logic since I am not sure if I really explained what is happening in enought detail also the MSG I am having trouble with are in Ladder 10 (Modbus MSG).BARSCREEN_3_ModbusRev2.RSS

Some of the managers here at our plant are getting new phones with Windows Moblie 6 and were intersted if there is a way they could view information from our SCADA on thier phones. Our SCADA software is RSView 32 and all of our PLCs are AB PLCs, most are SLC 5/05 with a few PLC 5s, CompactLogix, and MicoLogix 1100s and 1400s. Any information about any prouducts that might offer a soultion would be greatly appreciated, it does not have to be a Rockwell product but I figured since all of our PLC and SCADA software are Rockwell products it might make it easier if they made something. Thanks

I have two MicroLogix 1000 at two remote pump stations, I am needing to establish communication between the PLCs over leased lines from our phone company. The PLCs were communicating using serial radios however I am no longer able to get a reliable signal due to the growth of some trees adjacent to one of the pump stations. Raising the antennas are not an option any more. I have never used leased lines to communicate between PLCs but I have heard of it. The amount of data to move is very little, basicaly if station two gets a high wetwell I want to turn off the pumps at station one. If anyone could give me some pointers or links to learn more about this I would greatly appreciate it. Thanks in advance. Chris

Over the last few years I have noticed we seem to have a lot of NI8 cards fail. When they fail it faults the processor saying "a specialty I/O module has generated a generic fault". We have about 15 SLCs with at least one NI8 card, all of them have not had one fail but to the best of my memory only one SLC has ever had more than one fail in it, and it has had two fail. I am going to track which ones fail for now on to see if we can figure something out, but I am curious if anyone else has had trouble with these cards. Thanks

I am installing several 1746-OW16 relay output modules in an AB SLC 5/05 PLC. The relay contacts are being used to turn on a 24VDC isolation realy. I have read that add a MOV accross the coil of the isolation realys will extend the life of the realy contacts on the output modules. Can anyone suggest what type of MOV to use in this situation. Thanks

We are currently trying to standerize all the PLC in our plant to SLC 5/05. Presently we have a Modicon PC-E984-275 in use at a remote pump station I am wanting to change this PLC to a SLC 5/05. Would like to know if there is any software that would convert a progam wrote in Concept V2.2 to RS Logix to be used in the 5/05. I have a copy of the Modicon program on a disk but I don't have any programming software for the Modicon. Also if there is any software to do this any info. on how well it works, where to get it, and price would be appreciated. Thanks