Delta AS Series - Page 219

Chapter 7 Temperature Measurement Module AS04/08TC
7- 23
7_
Operand Data type Function Setting range Description
Tf REAL
Derivate-action
time constant
Range of
positive single-
precision
floating-
point numbers
(unit: sec)
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).
PID_EQ BOOL PID formula types
True: dependent formula
False: independent formula
PID_DE BOOL
The calculation of
the PID derivative
error
True: use the variations in the PV to
calculate the control value of the
derivative (Derivative of the PV).
False: use the variations in the error (E)
to calculate the control value of
the derivative (derivative of the
error).
PID_DIR BOOL
PID
forward/reverse
direction
True: reverse action; heating up
(E=SV-PV)
False: forward action; cooling down
(E=PV-SV)
ERR_DBW DWORD/DINT
Range within
which the error
value is counted as
0.
-32768~32767
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