Yokogawa EJX930A - Manual (Page 153)

A8-9
IM 01C25T02-01E
Bit Alarm status
D
IA
G
_H
_
A
LM
D
IA
G
_L
_
A
LM
FL
G
_
TE
M
P_
A
LM
5 Low Side Blocking 
6 High Side Blocking 
7 B Blocking  
8 Invalid Ref BlkF  
9 Invalid Ref fSPh 
10 Invalid Ref fSPl 
11 Invalid Ref fDP  
12 Outside Diagnosis Range  
13 Flg Temp Low Alarm 
14 Flg Temp High Alarm 
15 Reflect Blockage to PV/SV/TV
status
Note: The bit 13 and 14 are used for Heat trace monitorig
function.
 Outside Diagnosis Range
1) dpavgmax
The dpavgmax, DIAG_LIM [9], is the upper
limit of the diagnostic capability range. The limit
value can be changed when DIAG_MODE is
“Stop”.
VALUE_DPAVG indicates the ratio of the
average of differential pressure to the maximum
span regarded as 1. When VALUE_DPAVG
exceeds this limit, “Outside Diagnosis Range”
is generated so that the blockage detection
becomes impossible.
2) dpavgmin
The dpavgmin, DIAG_LIM [10], is the lower
limit of the diagnostic capability range. The limit
value can be changed when DIAG_MODE is
“Stop”.
When VALUE_DPAVG is below this limit,
“Outside Diagnosis Range” is generated so that
the blockage detection becomes impossible.
When the level range that can be measured by the
transmitter with 100 kPa span is -80 to 80 kPa, the
limits are set as follows.
• dpavgmax: 0.80
• dpavgmin: -0.80
1.000
0.000
0.80
-0.80
-1.000
Detectable
range
DPAvg
FA0807.ai
Outside Diagnosis Range
Outside Diagnosis Range
 Invalid Ref BlkF, fSPh, fSPl, or fDP
This alarm indicates that the reference value under
normal condition is invalid. If REFERENCE_BLKF
is invalid, the blockage detection excluding VALUE_
BLKF is carried out. If blockage detection function
based on VALUE_BLKF is required, obtain the
reference value again.
Also when REFERENCE_DPAVG is below DIAG_
LIM [10] or exceeds DIAG_LIM [9], all reference
value becomes invalid so that “Invalid Ref fDP”,
“Invalid Ref fSPl”, “Invalid Ref fSPh”, and “Invalid
Ref BlkF” are generated.
A8.2.5.4 Alarm Masking
 DIAG_OPTION
The alarms linked to an analog alert and LCD
display are selected by DIAG_OPTION in the
SENSOR Transducer block. The BIT of DIAG_
OPTION is corresponding to that of DIAG_ERR.
To link the alarm to an analog alert and LCD display,
follow the procedure below.
1) Set "Stop" to DIAG_MODE.
2) Check each checkbox of the alarm, which is
selectable from bit 2 to bit 14.
Note: The bit 13 and 14 are used for Heat trace monitoring
function.
Set to “Calculation” after setting the parameters.