Delta AS Series Manual page 219

Ch a pt er 7 Tem per at u r e M eas ur em ent M o d u le A S 0 4/ 0 8T C
Operand Data type
Tf REAL
PID_EQ
BOOL
PID_DE BOOL
PID_DIR
BOOL
ERR_DBW DWORD/DINT
Function Setting range
Range of
positive single-
Derivate-action precision
time constant floating-
point numbers
(unit: sec)
True: dependent formula
PID formula types
False: independent formula
True: use the variations in the PV to
The calculation of
the PID derivative
False: use the variations in the error (E)
error
True: reverse action; heating up
PID
forward/reverse
False: forward action; cooling down
direction
Range within
which the error
-32768~32767
value is counted as
0.
Description
If the derivate-
action time constant
is less than 0, Tf is
0 and it is not
controlled by the
derivate-action time
constant (derivative
smoothing).
calculate the control value of the
derivative (Derivative of the PV).
to calculate the control value of
the derivative (derivative of the
error).
(E=SV-PV)
(E=PV-SV)
The error value (E)
is the difference
between the SV
and the PV. When
the setting value is
0, the function
disabled; otherwise
the CPU module
checks
whether the present
error is less than
the absolute value
of ERR_DBW, and
checks whether the
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