Instruction manual

Instruction Manual
760006-A
September 2001
Rosemount Analytical Inc. A Division of Emerson Process Management Appendices 11-3
Model NGA 2000 Platform
ALARM TYPE COMMENTS
Concentration Programmable high/low, fail-safe/normal.
Warning Tied to Analyzer WARNING alarms, if Analyzer alarm reporting is enabled.
Failure Tied to Analyzer FAILURE alarms, if Analyzer alarm reporting is enabled.
System Failure Loss of communication with any module in the system.
Control Status Shows that remote control of range inputs is enabled.
Validity
Valid if: Analyzer operational state is normal; last span and zero did not fail, the
Analyzer is looking at the sample gas (not a calibration gas), no internal Analyzer
alarms are reported, the sample flow is greater than the lower limit, and the detector
temperatures are within limits (except for the CLD). There are other Analyzer spe-
cific problems which may affect validity also, such as flame out in a FID.
Table 11-2. Alarm Relay Configuration Matrix (v2.2)
Concentration
Can be expressed as a percentage of the
current range or as an absolute value of
gas concentration measured. Alarms can
be set to alert the user of low concentra-
tion, high concentration and percent of
range values.
Warning
Indicates one or more software-
configured limits on any network variable
(other than gas concentration) has been
exceeded. Examples of these secondary
variables are flow rate and internal volt-
age. A software reset or other resolved
software failure would also be reported.
In the event of a Warning alarm, gas con-
centration values displayed on the Op-
erator Interface or present on output lines
may not be accurate.
Failure
Indicates an unrecoverable hardware or
software failure such as some component
not responding to network communica-
tions or a safety related failure such as
lack of purge air in a Flame Ionization
Detection Analyzer module.
In the event of a Failure alarm, gas con-
centration values displayed on the Op-
erator Interface or present on output lines
will not remain accurate.
Control Status
Indicates that the Analyzer control has
been set to remote, in which case the in-
put lines on the I/O module are enabled.
Validity
Describes a condition in which gas con-
centration values present on the Operator
Interface or output lines should be con-
sidered invalid. The Analyzer module
alerts the system that an error in gas con-
centration is present. Causes include fail-
ure or lack of calibration, flame out in a
FID, or a not-from-process gas applied by
a sample control module.
The Analog I/O Module has the capability
of tracking a set range regardless of
which range the Analyzer module is on. It
is therefore possible to use several Ana-
log modules bound to one Analyzer to
provide multiple outputs at the same time.