Yokogawa Value Series FX1000 - Manual (Page 210)

9-5
IM 04L21B01-01EN
Computation and Report Functions (/M1, /PM1, and /PWR1 Options)
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Index
9.2 Writing Expressions
This section explains the meaning and how to write expressions.
Common Items
Follow the rules below when writing expressions.
• Use up to 120 characters to write expressions.
• The precedence of computing terms can be specified using parentheses.
• Specify the channels in the expression using channel numbers.
Example: 1, 12, and 101
Do not include channels that are set to Log scale (/LG1 option) in a computation
channel expression. If you include these channels, an error will be returned as the
measured result.
See section 3.13, “Using the Log Scale to Perform Measurements.”
• The one-digit number of constants (K), communication input data (C), remote input
terminal status (D), pulse input (P, Q), internal switch (S), alarm output relay status (I),
and flag (F) in the expression can be denoted as in “01” and “1.”
Example: K01, K1, C01, C1, D01, D1, P01, P1, Q01, Q1, S01, S1, I01, I1, F01, and F1.
• The data of the previous scan is used in the computation for its own channel number
and channel numbers greater than its own channel number in the expression.
• Write special computations (HOLD, RESET, and CARRY) and conditional expressions
at the beginning of expressions.
• You can specify the power measurement elements: active power, regenerative power,
reactive power (lead and lag), apparent power, voltage, current, frequency, and power
factor (/PWR1 option)
See section 3.12, “Measuring Power.”