I've got an ABB AC800M PLC (PM851) that I've installed at a customer's site. I also have two ABB PP845 10" touch panels and two signal towers with three colors (yellow/blue/green) connected to DO's through a couple of relays.

Is there a simple way of activating the yellow lamp for all unacked alarms with severity >600, the blue lamp for acked but active alarms and the green light when there are no active alarms?

I have searched the documentation for both the PLC and the panels but to no avail. I seem to remember seeing something about alarm groups based on severity in the panel software but can't find it today. I think the panel could detect the severity and status and then set an access variable which would could then be connected to the DO input. However I also think there should be an easier way of detecting an alarm in my code, without having to go through the panel.

(The long, tedious way would be to connect all GTHH/LTLL outputs to a Uni-block)

 

Yeah, because you are using a standalone AC800M unfortunately the long route is really the only way. The expectation for alarm handling is that you are either using Compact HMI or 800xA to filter and organize alarm lists coming out of the OPC-AE server, and in your case you don't have either.

There are however some ways you could at least make the code a little bit neater. There are some structured data types available in the Foundation Fieldbus library (FF) called Boolean16 and Boolean32. Even if you never use FF anywhere in your app, these data types make it much easier to pack and unpack boolean data because you can write direct to the individual bits of a word without doing any converts.

Connect the MVHH, MVLL etc to individual bits of each bool32 and then do your panel alarms on the Bool32. This should help to minimise the amount of variables or function blocks you need to write

Sorry I don't have a neat and tidy solution for you.

Rob
www[.]lymac.co.nz

 

Thanks for your reply, Rob! I don't have to worry about showing the alarms on the panels as they detect the A&E messages sent over OPC but I hoped there was a simple way to decide when to turn on the signal lights. As for the long way out I'm glad I've only got 60-70 alarms to handle...

You don't happen to know how to change the texts shown in the alarm list in the panel (ABB PP845) when using OPC A&E alarms? Right now it says "K411 *LL* Less than 100.00* when the K411 LL alarm is activated and my customer doesn't appreciate that. I thought you used the CondName-strings for (CondNameLL, CondNameHH etc) but they don't seem to make any difference.

 

Coldstart the application to make sure the AlarmCond blocks have been properly initialised with the Alarm strings.

Really, it depends what libraries you are using and how the AlarmCond blocks have been implemented, but usually a coldstart will kick them into life. It is also a good test that you have declared your "Retain" and "ColdRetain" variables correctly and you should really do this before you sign off on the completed application.

Rob
www[.]lymac.co.nz