Yokogawa EJX930A - Manual (Page 62)

<4. Diagnostics>
4-12
IM 01C25R02-01E
Bit
DD
(HART 5/HART 7)
DTM (HART 7)
DTM (HART 5) Category
0 Not used Not used
1 Not used Not used
2 A Blocking A Blocking
ILBD
3 Large Fluct L
Large Fluctuation
of Low Side
4 Large Fluct H
Large Fluctuation
of High Side
5 L Side Blocking Low Side Blocking
6 H Side Blocking
High Side
Blocking
7 B Blocking B Blocking
8 Invalid Ref F Invalid Ref BlkF
9 Invalid Ref SPH Invalid Ref fSPh
10 Invalid Ref SPL Invalid Ref fSPl
11 Invalid Ref DP Invalid Ref fDP
12 ILBD over range Outside Diagnosis
Range
13 FT low alarm
Flg Temp Low
Alarm Heat trace
monitoring
14 FT high alarm
Flg Temp High
Alarm
15 Not used Not used
Note: FT indicates the flange temperature.
 ILBD over range (Outside Diagnosis
Range)
• Procedure to call up the display
DD (HART 5/7)
DTM (HART 7)
[Root Menu] → Diag/Service → Diag
Parameters → ILBD Parameters →
Configuration → Diag Lim →
DTM (HART 5) Diag and Service → Advanced Diag
Configurations → Impulse Line
Blockage Detection → Threshold →
1) Lim DPAvgmax
Lim DPAvgmax is the upper limit of the
diagnostic capability range. The limit value can
be changed when Diag Mode is “Stop”.
DPAvg indicates the ratio of the average of
differential pressure to the EJX maximum span
regarded as 1. When DPAvg exceeds this
limit, “ILBD over range” is generated so that the
blockage detection becomes impossible.
2) Lim DPAvgmin
Lim DPAvgmin is the lower limit of the
diagnostic capability range. The limit value can
be changed when Diag Mode is “Stop”.
When DPAvg is below this limit, “ILBD over
range” is generated so that the blockage
detection becomes impossible.
4.2.2.5 Alarm and Alert Setting
The abnormal results as the blockage detection and
high/low flange temperature (heat trace monitoring)
are given through an analog alert or the LCD
display of alarm status. Before performing the ILBD
operation, it is necessary to set the alarm and alert
according to the following procedure.
Storage of Abnormal results
(Diag Error)
Alarm Masking
(Diag Option)
Outside Diagnosis Range/
Invalid Ref xx
Masking
Alarm on
Analog Output
Alarm on
Status Output
Device Status
Field Device More Status Available
Additional Device Status
(Status group 9 and 10)
Alarm Display
on LCD
F0408.ai
Figure 4.6 Alarm and Alert Setting
 Alarm Status
When the algorithm of ILBD and Heat trace
monitoring detect the abnormality, the result is
stored in Diag Error. The alarm status based on the
detected abnormality is displayed to Diag Error.
(Displayed to Impulse Line Blockage Detection
and Heat Trace for DTM(HART 5))
• Procedure to call up the display
DD (HART 5/7)
DTM (HART 7)
[Root Menu] → Diag/Service → Diag
Parameters → Diag Error →
DTM (HART 5) Diag and Service → Advanced Diag
Alerts → Diag Error