Index – Yokogawa DAQWORX User Manual
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IM WX102-01E
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Index
Before Operation
Computing equations are set according to the following rules:
The number of computing equations
Thirty computing equations for the stand-alone type and sixty for the expandable type
can be set. Each computing equation is assigned a number. The numbers are A01 to
A30 for the stand-alone type and A01 to A60 for the expandable type. These numbers
are called computation channel numbers.
Data to be computed
• Measured data: Specified with channel numbers (example: 050).
• Computed data: Specified with computation channel numbers.
• Constants: 30 constants for the stand-alone type and 60 constants for the expanded
type can be set. Each constant is expressed by a number from K01 to K60 (K01 to
K30 for the stand-alone type).
Priority of operators
The priority of operators in a computing equation is as follows. The operators are placed
in order from the highest priority.
Type
Operators
Function
ABS(), SQR(), LOG(), LN(), EXP(), MAX(), MIN(), P-P(), SUM(), AVE(),
PRE(), HOLD():, RESET():, PSUM()
Power
**
Signs, logical negation
+, -, NOT
Multiplication, division
*, /
Addition, subtraction
+, -
Greater/less relation
.GT., .LT., .GE., .LE.
Equal/not equal relation .EQ., .NE.
Logical product
AND
Logical sum, exclusive
OR, XOR
Range when computing
When the value exceeds ±10308 during the computation, a computation error (overflow)
occurs.
Units in computing equations
In computations, measured data are handled as numbers without units. For example, if
the measured data of channel 001 is 20 mV and the measured data of channel 002 is 20 V,
the computed result of 001+002 becomes 40.
Limitations in computing equations
Multiple operators can be used in one computing equation. But, there are following
limitations.
• The number of characters that can be used : 40 characters
• The total amount of channel numbers and constants: 16 (Computation error occurs
when 16 is exceeded, and the computed result becomes +OVER or –OVER)
• Computation channel numbers: Computation channel numbers less than the current
computation channel number can be used as variables within the computing equation.
Example: A02=001+A01 Computation channel numbers greater than or equal to A03
can not be used in this computation.
• Statistical operators (TLOG. or CLOG.) can only be used once in one computing
equation.
1.5 DA100 Functions