Help with Siemens Protool HMI alarm messaging

This is a different problem but on the same machine as my other post.

Basically there is an alarm message showing up on the TP270 HMI, and I am trying to find the bit that is triggering it in the S7-300 PLC program but I can't find it.

The alarm message coming up is listed as alarm message 10 "IGS01 CALIBRATION LOST ERROR".

If you go to Area Pointers setup in ProTool you can see that the Alarm Messages pointer is set to DB6.DBW0.

With this information you would assume that alarm message 1 = STAT0 = DB6.DBX0.0, therefore alarm message 10 = STAT9 = DB6.DBX1.1, however this is not the case.

When the alarm is active, DB6.DBX1.1 is false.

So then I tested another alarm, alarm message 49 "MELT PUMP OIL COOLER/HEATER NOT RUNNING".

You would think that alarm message 49 = STAT48 = DB6.DBX6.0, but when I was triggering the alarm condition on and off I could see that it was in fact STAT56 or DB6.DBX7.0 triggering the alarm message.

I have attached DB6 and some screenshots of the alarm message setup in ProTool.

Can anyone explain this behaviour?

brendan.buchan said:

With this information you would assume that alarm message 1 = STAT0 = DB6.DBX0.0, therefore alarm message 10 = STAT9 = DB6.DBX1.1, however this is not the case.

When the alarm is active, DB6.DBX1.1 is false.



Can anyone explain this behaviour?

Click to expand...

Are you sure that Alarm1 isn't DB6.DBX0 and Alarm 10 DB6.DBx1.1?
I assume it is a Siemens PLC.
I didn't get a chance to loo at the attached files!

bkottaras said:

Are you sure that Alarm1 isn't DB6.DBX0 and Alarm 10 DB6.DBx1.1?
I assume it is a Siemens PLC.
I didn't get a chance to loo at the attached files!

Click to expand...

I meant Alarm 1 = DB6.DBX1.0 and Alarm 10 = DB6.DBX0.1

When you specify the range for the alarm messages, Siemens is "Very helpful" in incrementing in groups of 16 (The length of a word)so message numbers 1- 8 would set by F 201.0 - 201.7 and message numbers 9 - 16 by F200.0 - 200.7 . It's a little confusing when the higher byte operates the lower messages!

D'Oh - this is really what "Bkottaras" is saying. I really should learn to read!

Thanks guys.

I'm away from work and the machine at the moment but I think it is starting to make sense.

What a backwards way of doing things.

Can't wait until this problem is fixed so I can get back to working on 'normal' Allen Bradley PLCs

Big Endian / Little Endian

http://en.wikipedia.org/wiki/Endianness