Airthmetic (Arthm) Function Block - Emerson Rosemount OCX 8800 Reference Manual

Foundation Fieldbus
Table 7-29: Troubleshooting
Symptom
Mode sheds form ROUT to MAN
Process and/or block alarms will not
work.
7.10

Airthmetic (ARTHM) function block

The arithmetic function block provides the ability to configure a range extension function
for a primary input and applies the nine different arithmetic types as compensation to or
augmentation of the range extended input. All operations are selected by parameter and
input connection.
Figure 7-24:
172
(continued)
Possible causes
1. Remote output value
2. Shed timer
1. Features
2. Notification
3. Status options
Arithmetic (ARTHM) function block
Corrective action
1. Host system is not writing ROUT_IN
with a quality and status of good
cascade within shed time (see 2 be-
low).
2. The mode shed timer, SHED_RCAS,
in the resource block is shed too low.
Increase the value.
1. FEATURES_SEL does not have Alerts
enabled. Enable the Alerts bit.
2. LIM_NOTIFY is not high enough. Set
equal to MAX_NOTIFY.
3. STATUS_OPS has Propagate Fault For-
ward bit set. This should be cleared to
cause an alarm to occur.
OCX 8800