7
In DTB series, P (Proportional Band), I(Integral Time) and D(Derivative
Time) parameters are automatically set by using the Auto-tuning (AT)
function.
: This parameter is for the control mode that must be Dual Loop
output control with PID control method configured. The value of P, I and D of
1st output group can be set immediately. The P value of 2nd output group is
equal to (P value of 1st output group) x
and the value of I and D of
2nd output group are the same as the value of I and D of 1st output group.
: Dead Band, shown as the following figure 1, 2 and 3. This
parameter sets an area in which the heating and cooling control output is 0
centering around the set point in a Dual Loop output control mode.
:
Settings lock.
To avoid incorrect operation, two key lock functions
are provided.
: Lock 1 can lock all settings. All parameters and
temperature settings can be locked to disable changes.
: Lock 2
can lock settings except the SV (Set point) value. All parameters and
temperature settings can be locked with the exception of the SV value.
Press
and
key simultaneously, the “Lock” status can be
released.
PV
0
Output
Dead band: dead
band width=negative
Set point
Heating
Cooling
Figure 3. PID
Dead Band is negative
control,
8
Alarm
Outputs
There are up to three groups of alarm outputs and each group allows thirteen alarm types in the initial setting
mode. The alarm output is activated whenever the process temperature value (PV) is getting higher or lower than
the set point of alarm limit.
Set
Value
Alarm Type
Alarm Output Operation
0
Alarm function disabled
Output is OFF
1
Deviation upper- and lower-limit:
This alarm output operates when PV value is higher than the setting value
SV+(AL-H) or lower than the setting value SV-(AL-L).
ON
OFF
SV-(AL-L)
SV
SV+(AL-H)
2 Deviation
upper-limit:
This alarm output operates when PV value is higher than the setting value
SV+(AL-H).
ON
OFF
SV
SV+(AL-H)
3 Deviation
lower-limit:
This alarm output operates when PV value is lower than the setting value SV-(AL-L).
ON
OFF
SV
SV-(AL-L)
4
Reverse deviation upper- and lower-limit:
This alarm output operates when PV value is in the range of the setting value
SV+(AL-H) and the setting value SV-(AL-L).
ON
OFF
SV
SV-(AL-L)
SV+(AL-H)
5
Absolute value upper- and lower-limit:
This alarm output operates when PV value is higher than the setting value AL-H or
lower than the setting value AL-L.
ON
OFF
AL-L
AL-H
6
Absolute value upper-limit:
This alarm output operates when PV value is higher than the setting value AL-H.
ON
OFF
AL-H
7
Absolute value lower-limit:
This alarm output operates when PV value is lower than the setting value AL-L.
ON
OFF
AL-L
8
Deviation upper- and lower-limit with standby sequence:
This alarm output operates when PV value reaches set point (SV value) and the
value is higher than the setting value SV+(AL-H) or lower than the setting value
SV-(AL-L).
ON
OFF
SV
SV-(AL-L)
SV+(AL-H)
