Yokogawa EJX930A - Manual (Page 152)

<Appendix 8. Advanced Diagnostics>
A8-2
IM 01C25R03-01E
 Functional block diagram
The figure below shows the functional block diagram of ILBD, which is performed in the SENSOR Transducer
block.
block AI
Function block block AI
Function block
EJX
(1)
(2)
(3)
(4)
(5)
(6)
FA0801.ai
Output of AI
Sensor
Sensor
signals
SENSOR
Transducer block
Process value
calculation
Blockage degree
Execution of
ILBD
Alarm
Masking
block AI
Function block
Add result of
blockage detection to status
Resource
block
LCD Transducer
block
Values of blockage degree
Result of
blockage detection
Result of
blockage detection
Blockage alarm
Blockage alarm
AI.OUT
STB.RATIO_FDP
STB.RATIO_FSPL
STB.RATIO_FSPH
STB.VALUE_FSPH
STB.VALUE_FSPL
STB.VALUE_FSPH
STB.VALUE_BLKF
RS.DEVICE_STATUS_7
STB.DIAG_ERR
STB.DIAG_H_ALM
STB.DIAG_L_ALM
Display on LCD
Figure A8.1 Functional Block Diagram of ILBD
The following outputs are given for the ILBD results.
Table A8.1 List of Outputs for ILBD
FA0802.ai
RATIO_FDP
The result of blockage detection can be set to “UNCERTAIN: Non Specific” if
DIAG_OPTION has been set to indicate the alarm status.
Parameters based on the fluctuation value and blockage degree
[ COMP_FLG: Non-Compensation ]
[ COMP_FLG: Compensation ]
When an impulse line blockage is detected, the result of the blockage detection
(alarm status) is indicated.
When an impulse line blockage is detected, the results of the blockage detection
(alarm status) are indicated.
When an impulse line blockage is detected, an alert is generated by divided into
high- and low-pressure sides.
Blockage degree characterized in comparison of high-pressure side and
low-pressure side pressure fluctuation value
When impulse line blockage is detected, an alarm status is displayed on LCD.
Average value of the sum of squares of differential pressure fluctuations
Average value of the sum of squares of high-pressure side static pressure fluctuation
Average value of the sum of squares of low-pressure side static pressure fluctuation
#
Parameter name
OUTPUT
Block
Remarks
AI function block OUT
RATIO_FSPH
VALUE_BLKF
SENSOR
Transuducer Block
Resource block DEVICE_STATUS_7
SENSOR
Transducer block
SENSOR
Transducer block
DIAG_ERR
DIAG_H_ALM
DIAG_L_ALM
VALUE_FDP
VALUE_FSPL
VALUE_FSPH
Display on LCD
(1)
(2)
(3)
(4)
(5)
(6)
= RATIO_FDP
X REFERENCE_DPAVG = RATIO_FDP
VALUE_DPAVG
= RATIO_FSPL
= RATIO_FSPH
RATIO_FSPL VALUE_FSPL
REFERENCE_FSPL
VALUE_FSPH
REFERENCE_FSPH
VALUE_FDP
REFERENCE_FDP
VALUE_FDP
REFERENCE_FDP