NorOntScout

This is what I found on the subject https://rockwellautomation.custhelp.com/app/answers/detail/a_id/22114 How to read and write to tags using vba on SE. Basically: Option Explicit Public WithEvents oGroup As TagGroup ' Define a TagGroup Public Function ReadTagValue(strTagName As String) As Variant     Dim oTag As Tag Set oGroup = Application.CreateTagGroup(Me.AreaName, 500) 'Set the tag group as being part of the Project oGroup.Active = False 'Stop updating of tag group On Error GoTo ErrorTrap     oGroup.Add strTagName  'Add tag to TagGroup     oGroup.Active = True 'Update Tag from PLC / DB     Set oTag = oGroup.Item(strTagName) 'Define Tag     Err.Clear 'Clear errors     ReadTagValue = oTag.Value 'Get tag value and store it     Set oTag = Nothing 'Clear tag     Set oGroup = Nothing 'Clear Group     Exit Function ErrorTrap:      LogDiagnosticsMessage "Error in ReadTagValue. Error: " & Err.Description      Err.Raise Err.Number, "ReadTagValue()", "Error:" & Err.Description  End Function    

Working on a conversion for a client. Converting their existing VAX system to be replaced by SE. Some of the background functions will be split between the PLC and some VBA routines in the SE. The issue I have during in house testing of the VBA is that I can read the PLC, I can read about 4 tags and then it fails. I get "VBA Code has been halted. Reason: Run-time Error - Error: Unable to read the tag '/xxxx' "   Not sure if it is configuration issue or something else.   So what I would like to know is where do I start looking ?   I can post snippets of the code if so desired.   NorOntScout

Simple Question (I think), difficult finding an answer. Have a customer asking to concentrate the various HMI (FT ME) Alarms from around the plant to one location / destination. I have looked about but am having a hard time finding an answer. A) Is it possible ? B) What is required ? C) Do I need to modify the existing HMI runtimes (of which I don't have yet) to accomplish this ? I was reading the FT Alarms and Events blurp on the Rockwell Automation website, which is indicating such is possible, but it also indicates I require using the Alarm AOI from Rockwell to make it work. This option may be difficult to implement as the client has their own programming standards / architecture that prevents using non approved AOI / structures. What is possible ? What is suggested to accomplish this ? Regards,

I will see what I can do the next site visit to try these things and implement them. Marc

variable based on 4-20ma signal

Essentially this is a bank of floatation cells. Add your slurry to the tank, which contains your desired material, the garbage and a chemical reagent. Feed the tank at a rate of X ton/hr, add air to create a froth at the top, maintain a fixed level allowing the froth to bubble over and collect it for further processing. The slurry is constantly flowing from one tank to the next. each tank has a step down in installed height. Tank 5 is at floor level, Tank 4 is 24" off the floor, Tank 3 is 48" off the floor, etc allowing for some natural head to be acheived between each tank. I have static feed rate into the tank according to the operators, but I also have an uncontrolled adder to the feed when they wash down the floors, all the floor drains get fed back into my feed which is the highest source of fluctutaions. Usually what occurs during this period Tank 1 receives a sudden increase in tank height, the controller reacts by opening the pinch valve. Tank 2 reacts in the same manner. Tank 3 shortly there after reacts the same, etc Tank 1 starts to see it is losing height too quickly and starts clamping down on flow, Tank 2 gets the same reaction, etc, see the pattern ? I have tried tuning with my limited experience as possible. I had some really wild swings initially and played with it, now my swings are not so wild but the system is slow to react to all surges. the small disturbances are not an issue but the larger ones are. Does this help to describe the process a little better ? Marc

Not sure if I follow. Each Tank has radar reading a float for level indication and using a pinch valve for the discharge port. What you suggest is to leave the Tank 2-5 inputs alone, continue to feed the levels to each PV input on the PID block, but add an intermidiate block for Tank 1. So for Tank 1 I would have the Level go to an Averaging block, from the averaging block I would take this to the PV input on the PID block ? Most surges last up to 5 or 10 minutes, and at current configuration creates a series of fluctuation on the system that last up to 30 minutes. After this period all the tanks have stabilized again. Having the averaging block there wouldn't it cause the system to react slower to the incoming surge ? The honeywell controller is a rebranded red lion system. Kind of wishing the system would have let take the logs from the hmi. Marc

Hello All, Looking for help in setup for a 5 loop PID system. I am not a process engineer but do a lot of large equipment automation projects. I have 5 Tanks using Level control (Radar) and a discharge valve on each tank. The 5 tanks are connected in series. Tank 1 receives liquid from the plant at various rates uncontrolled by me. Tank 1 feeds Tank 2 through the Tank 1 discharge valve. Tank 2 feeds Tank 3 through the Tank 2 discharge valve, etc until Tank 5 which simply discharges to further processing by other equipment. They are currently in operation as 5 independent loops. As you get a large disturbance on Tank 1 you can see it cascade out to the other tanks in sequence. I have tried reducing this reaction by increasing P and decreasing I as you go down the system, which seems to have helped. Using a Honeywell HC900 controller with 4-20ma signal control. The PID function block selected in controller are set to PID A control (3 mode control) no SP tracking, P is gain (No units), I is Reset (Minutes), D is Rate (Minutes) and not used. Feedforward gain is available but not being used. I do not have the process modeled, I did initial tuning by WAG. My questions 1 - can I cascade these loops using Tank 1 as the central loop, since it has the largest disturbances, and the other tanks connecting in order of flow. 2 - How do I do this. 3 - Is there another way to better handle the fluctuations Let me know if I am missing some information and I will endeavour to provide it to allow better assistance. Marc

I agree with Micheal Smith. Works have been using it for a couple months now. Pulsar2003 transfer your licenses from the Floppy to a USB. Virtual machine has no problems with the USB memory. I actully copied my keys to the virtual machine and have not had any problems to date.

I will my .02 cents. I am running Win 7 pro with Windows Virtual PC. Works well so far. Installing any of the FT software requires the intergration feature to be disabled. Connecting to the outside world is tricky sometimes. Map your Ethernet cards correctly. Install your USB drivers under the Virtual machine. I used an OMRON usb/rs232 adapter to talk to a micrologix, attempt 1 had the serial ports mapped through the win7, worked once. all subsequent connections required the virtual machine to take ownership of the serial adapter which required the dirver be installed under the virtual machine. Never had any issues yet with the ethernet. I am running 3 Virtual machines. 1 has AB software with all the latest, 1 has AB software with what we actually use, 1 is for siemens. I would recommend a minimum of 8GB for your laptop if you plan on running multiple Virtual machines at once. Also edit some of the Virtual machine settings with a text editor so as not to cause hardware availability conflicts.