FactoryTalk View ME - Can I alarm off of Binary?

This is the first project I've configured in FactoryTalk View ME. I have experience programming in InTouch, so trying to figure out the way alarming works in FT is frustrating.

I have my alarms set up in RSLogix 500. The alarm condition (either a comparing instruction or a digital bit) will turn on a B15/x bit. This bit will seal itself in until the PLC receives the HMI Acknowledge bit.

When I configure the Alarm in FT, I have the tag TANK_PSI_HIHI with a device address of B15/x. I have the alarm trigger set to this tag, with a trigger value of 1. When I run my application, I get a message: {ALARMS\TANK_PSI_HIHI}: This trigger has been disabled as its data type is not supported by Bit or LSBit triggered alarms.

Does this mean that FTView can not alarm off of binary bits? All the examples I see from a Google search and a forum search use mapping the digital bits into an N Alarm word... is this the only way? I would prefer not to do this (since I have already set up all my binary alarm bits), so if there is a work around, I'd love to hear it.

Thanks for your attention.

Steve

Change the Trigger Type to "Value" instead of "Bit" and that should resolve the error message. In this context, "Bit" means "Bit subelement of a Word".

There is a good Knowledgebase document that discusses the various approaches to trigger and alarm management in FTView ME, with an eye towards communication efficiency.

http://rockwellautomation.custhelp.com/app/answers/detail/a_id/36748/

I've done something similar in FTView but with a CompactLogix. I set the Trigger type to Value and call out the tag to the bit level; {::[Redpit]Program:MainProgram.Sys_In_Status.5} where each bit in the word is defined, in this case bit 5. I don't know if this will work with the B file in RS500.

This was a little confusing for me the first time I tried it as well. You can do this a couple of different ways:
Method 1 - This is the way I have handled these in the past. In the Alarm Setup dialog box, Add B15.0 as a trigger and give it a label i.e. "Alarm Word 1". (If you have more than 15 alarms you'll have to add each word used for alarms as another trigger B15.1, B15.2, etc., which will be "Alarm Word 2", "Alarm Word 3", etc.) Use the trigger type of "Bit". Now move to the "Messages" tab. Here, the "Value" column corresponds to the specific bit location with the Alarm Word, except that FTView starts counting at 1 instead of 0. So the alarm associated with B15/0 will have Trigger = Alarm Word 1, and Value = 1. B15/1 will have Trigger = Alarm Word 1, and Value = 2, and so on. The only caveat I remember here is that for some reason you cannot use the last bit in any word, so you can only use B15/0 through B15/14 (this can also be displayed as B15.0/14) before you have to move on to B15/16 (or B15.1/0). B15/16 would correspond to Trigger - Alarm Word 2, Value = 1. This method reduces the total number of tags that have to be updated within the HMI. I believe this cuts down on network traffic since the HMI is able to update the entire word at once instead of 15 separate tag updates (not too sure about this part though).

Method 2 - Create a new trigger for each alarm bit, but then change the trigger type to value. This does not mean that you can't use bits, just that you get the choice of whether to trigger the alarm when the value = 0 or 1 in the Message tab. Works just as well, but requires setting up more triggers and creating more tags that need to be updated.

Hope this helps. I'm not too sure it's as clear as I'd like. That's what I get for not getting any sleep.