Experimental Physics and
Industrial Control System

Marty Kraimer <[email protected]> · Tue, 25 Nov 1997 13:14:52 -0600

Mark M. Ito wrote:
> 
> What is the difference between alarm status and alarm severity? Are these
> terms defined in any of the documentation?
> 
> Mark M. Ito, Thomas Jefferson National Accelerator Facility
> 12000 Jefferson Ave., Mail Stop 12H, Newport News, VA 23606
> Email: [email protected], Office: (757)269-5295, Pager: (757)680-7175
> WWW: http://claspc2.cebaf.gov/~marki/

Alarm severity has one of the following values

NO_ALARM
MINOR_ALARM
MAJOR_ALARM
INVALID_ALARM

INVALID_ALARM means that the value is invalid, i.e. it is not known
if the value represents reality. For example if an analog input module
fails the values are invalid.

Status is an indication of what causes an alarm. There are a fixed set
of status values defined in base/include/alarm.h. Some examples are

READ_ALARM - set when input devices fail
WRITE_ALARM - set when output devices fail
HIHI_ALARM - set by analog type records when the value exceeds HIHI

and so on. See alarm.h for details.

The Application Developer's Guide discusses the algorithm for setting
alarms.

Marty Kraimer

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System