Yokogawa EJX930A - Manual (Page 47)

<6. Explanation of Basic Items>
6-8
IM 01C25R03-01E
BASIC Mode Setting Procedure
(1) Set the operation mode to O/S.
(2) Select easy flow calculation at FLOW_
CALCULATION_MODE.
(3) Select the fluid code (liquid or gas) at
FLUID_TYPE_CODE.
(4) Select the flow equation in the following
table from the fluid type (liquid/gas) and flow
unit category (mass flow/standard volume
flow/volume flow).
T0601.ai
Fluid
type
Flow unit
Category
Flow equation
Liquid Mass Flow
Normal-Standard
Volume Flow
Volume Flow
Qm or Qv or Qv norm *1
=Kfactor
× ∆P × (1+Temp K1 × (T-Tb))
Gas Mass Flow
Normal-Standard
Volume Flow
Volume Flow
Qv=Kfactor *1
× ∆P × T/Tb × SPb/SP
Qm or Qv norm *1
=Kfactor
× ∆P × Tb/T × SP/SPb
*1 Custom setting Parameter
(5) Set the required data (values marked by
==== in the above table) to the following
parameters.
• Kfactor → FIXED_FLOW_VALUE
• Temp K1 → TEMP_K1_FOR_LIQUID
• Tb → REF_EXT_TEMP_TERATURE
• SPb → REF_STATIC_PRESSURE
(6) Set the operation mode to AUTO.
NOTE
To confirm the setting of flow calculation, use
Simulation Function. See ‘6.3.6 Simulation
Function.’
6.4.4 Flow Unit/Decimal Point Digit
The flow unit is indicated in the FLOW_VALUE_
UNIT parameter and the number of digits past
the flow decimal point is indicated in the FLOW_
VALUE_DECIMAL parameter. As the content
of these parameters is interlocked with sub
parameters Unit and Decimal of XD_SCALE in the
AI function block where the flow signal is selected,
FLOW_VALUE_UNIT and FLOW_VALUE_
DECIMAL also are automatically changed when
XD_SCALE.Unit and XD_SCALE.Decimal are
changed.
6.4.5 Flow Type Selection
Mass flow, volume flow and standard volume
flow are automatically selected according to the
flow unit. The currently selected flow type can be
referenced at the FLOW_VALUE_TYPE parameter.
6.4.6 BLOCK_ERR
The BLOCK_ERR parameter indicates the cause
of errors that occur in the block. On the FLOW
transducer block, check the following error causes,
and set the bit corresponding to the cause.
Bit Name
Measurement function
Multi Sensing
Mass Flow
Measurement
0 Other Setting error *1 Compensation
coefficient setting error *2
Precision flow setting
checksum error *3
15 Out of
Service
Not supported O/S is set for ModeBLK.
Target.
*1: The mode other than O/S is set for ModeBLK.Target.
*2: The flow value is zero or less. This is supported only in the
Auto Compensation mode.
*3: The sum value of the Auto Compensation flow setting
does not agree with the value when it was written by the
setup tool.
6.4.7 XD_ERROR
The XD_ERROR parameter indicates the most
important error code among the errors that are
currently occurring on the FLOW transducer block.
The following table summarizes the content of
supported XD_ERRORs and error codes.
When two or more error codes are being generated
simultaneously, error codes are displayed with
preference given to the largest error code.
Error
Code Error Name
Description
Support
Multi
Setting
Mass Flow
Measurement
15 Out of
Service
FLOW TB is in the
O/S mode.
— 
19 Configuration
error
Other than O/S is
set even though it
is a Multi Sensing
type.
 —
23 Data Integrity
Error
The flow setting
sum value does
not agree with
the value when it
was written by the
setup tool.
— 
15 Algorithm
Error
The flow value is
smaller than zero.
— 