Brainchild C21 User Manual page 37

then increase OFST 25 %, and vice versa. After adjusting OFST value, then increase OFST 25 %, and vice versa. After adjusting OFST value,
the process value will be varied and eventually, coincide with set point. the process value will be varied and eventually, coincide with set point.
Using the P control ( TI set to 0 ), the auto-tuning is disabled. Using the P control ( TI set to 0 ), the auto-tuning is disabled.
Refer to section 3-12 " manual tuning " for the adjustment of PB and Refer to section 3-12 " manual tuning " for the adjustment of PB and
TD. Manual reset ( adjust OFST ) is not practical because the load may TD. Manual reset ( adjust OFST ) is not practical because the load may
change from time to time and often need to adjust OFST repeatedly. change from time to time and often need to adjust OFST repeatedly.
The PID control can avoid this situation. The PID control can avoid this situation.
Heat only PID control : Heat only PID control :
not be zero. Operate auto-tuning for the new process, or set PB, TI not be zero. Operate auto-tuning for the new process, or set PB, TI
and TD with historical values. See section 3-11 for auto-tuning and TD with historical values. See section 3-11 for auto-tuning
operation. If the control result is still unsatisfactory, then use manual operation. If the control result is still unsatisfactory, then use manual
tuning to improve the control . See section 3-12 for manual tuning. The tuning to improve the control . See section 3-12 for manual tuning. The
unit contains a unit contains a
small overshoot and very quick response small overshoot and very quick response
tuned. tuned.
Cool only control:ON-OFF control, P ( PD ) control and PID Cool only control:ON-OFF control, P ( PD ) control and PID
control can be used for cool control. Set OUT1 to DIRT ( direct control can be used for cool control. Set OUT1 to DIRT ( direct
action ). The other functions for action ). The other functions for
only P ( PD ) only P ( PD ) control and control and
descriptions for heat only control except that the output variable descriptions for heat only control except that the output variable
( and action ) for the cool control is inverse to the heat control. ( and action ) for the cool control is inverse to the heat control.
NOTE : NOTE : The ON-OFF control may result excessive overshoot and The ON-OFF control may result excessive overshoot and
undershoot problems in the process. The P ( or PD ) control will result undershoot problems in the process. The P ( or PD ) control will result
in a deviation process value from the set point. It is recommended to in a deviation process value from the set point. It is recommended to
use PID control for the Heat-Cool control to produce a stable and zero use PID control for the Heat-Cool control to produce a stable and zero
offset process value. offset process value.
Other Setup Required : Other Setup Required :
O1TY & O2TY are set in accordance with the types of OUT1 & OUT2 O1TY & O2TY are set in accordance with the types of OUT1 & OUT2
installed. CYC1 & CYC2 are selected according to the output 1 type ( installed. CYC1 & CYC2 are selected according to the output 1 type (
O1TY ) & output 2 type ( O2TY ). Generally, selects 0.5 ~ 2 sec. for O1TY ) & output 2 type ( O2TY ). Generally, selects 0.5 ~ 2 sec. for
CYC1, if SSRD or SSR is used for O1TY; 10 ~ 20 sec. if relay is used CYC1, if SSRD or SSR is used for O1TY; 10 ~ 20 sec. if relay is used
for O1TY, and CYC1 is ignored if linear output is used. Similar condition for O1TY, and CYC1 is ignored if linear output is used. Similar condition
is applied for CYC2 selection. is applied for CYC2 selection.
Selecting REVR for OUT1, PB and TI should Selecting REVR for OUT1, PB and TI should
very clever PID and Fuzzy very clever PID and Fuzzy
cool only PID cool only PID
O1TY, CYC1, O2TY, CYC2, O1FT, O2FT O1TY, CYC1, O2TY, CYC2, O1FT, O2FT
algorithm to achieve a algorithm to achieve a
to the process if it is properly to the process if it is properly
cool only ON-OFF cool only ON-OFF
control are same as control are same as
UM0C911A
very very
control, control, cool cool
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