To show @ispresent available on OPC Client

[itong 0]

Hello, Somebody can tell me how to show the predefine items on controllogix5000 for instance @ispresent, @switchtopic? I created topic, and using RSI-OPC Test Client to browse for those items but I couldn't see them. Any help will be appreciated... Cheers, ITong

[rpraveenkum 5]

DDE/OPC predefined items RSLinx can obtain general processor information or trigger events using DDE/OPC predefined items. The following predefined items can be used with all PLC types: @Mode returns the current mode of the processor as a string (Run, Program, Remote Run, or Remote Program). @ProcessorName returns the name of the program running in the processor. @Revision returns the firmware version of the processor as a string. @PLCType returns the processor type as a string. @Status returns the current status of the processor as a string (Ok or Faulted). @StatusNumber returns the current status of the processor as a number. @SwitchTopic is used to switch between alias topics in OPC clients. The following predefined items are used with Logix5000 family processors: @FreeMem returns total unused memory (I/O + data table + general). @FreeMemDT returns unused data table memory (not applicable to 1756-L1). @FreeMemGM returns unused general memory (applicable to 1756-L55M16 only). @FreeMemIO returns unused I/O memory. @TotalMem returns total available memory (I/O + data table + general). @TotalMemDT returns total available data table memory (not applicable to 1756-L1). @TotalMemGM returns total available general memory (applicable to 1756-L55M16 only). @TotalMemIO returns total available I/O memory. @CLTagUpdateAddressSpace forces RSLinx to update its' Logix5000 tag database. @RedundancyMode monitors the processor state in a ControlLogix redundant system. @IsPresent allows you to check if your ControlLogix processor is available prior to performing reads or writes. The time out value is consistent with the communications timeout value in the configured PLC-5 topic. for this data type should be String

[Tim Raines 0]

Hello itong and rpraveenkum, I too have been trying to real the @IsPresent status bit from a ControlLogix processor via an OPC Client. I'm trying to use the status bit in software from SyTech called XLReporter. When I contacted Rockwell Tech Support, they said that I had to create an OPC Topic Item and configure the data collection processor type as a PLC-5 instead of Logix 5000. I had already been using a topic with a processor type of Logix 5000 and could browse in tags, but of course could not browse in the predefined tags such as @IsPresent. I created the new topic as they told me with the PLC-5 as the processor type, but I cant see ANY tags to browse. Anyone out there have an idea what to do? Thank you, Tim

[rpraveenkum 5]

Check the topic targeted to the processor? try to link it with MS excel to test

[Tim Raines 0]

Tuesday, September 11, 2007 Praveen, I found out how to display the "@IsPresent" status from the RSI OPC Test Client! I was expecting to be able to browse the tag. When the Topic is configured with the processor type as PLC-5, you can't see any tags. Configure the Topic with the processor type as Logix 5000 and the Tags appear (except the "@" status type tags) and of course can be browsed in. Well, all you have to do to get the Topic with the processor type set to PLC-5 to work is just type the processor and tagname in the ITEM NAME box on the ATTRIBUTES tab using the RSI OPC Test Client! For example, to get back a value for the "@IsPresent" with a PLC processor named "BOILER", here is what one would type in the box: [bOILER]@IsPresent If you are using ControlLogix, and don't mind getting back a string value instead of a number, you don't have to add a new topic with the processor type set to PLC-5 to get the processor status. Instead, just use configure the topic as you usually would (Processor type set to Logix 5000), and use the @Status. If all is well, @ Status will return an "OK" string to you! Anyway, maybe this will help others with the same problem as the Tech Bulletin in the RSI website is not very clear on this matter. Thank you, Tim --------------------------------------------------------------------------------------------------------------------------

[rpraveenkum 5]

Tim, I think you got it Same thing can be done using logic in the processor to set or reset a bit with time delay