Brainchild P41 User Manual page 48

PV
SP1
SP1 O1HY
Output 1 Action
ON
OFF
Figure 3.2 Heat Only ON-OFF Control Figure 3.2 Heat Only ON-OFF Control
The ON-OFF control may introduce excessive process oscillation even The ON-OFF control may introduce excessive process oscillation even
if hysteresis is minimized to the smallest. If ON-OFF control is set , PB1, if hysteresis is minimized to the smallest. If ON-OFF control is set , PB1,
TI1,TD1, PB2, TI2, TD2, CYC1, CYC2, OFST, CPB and DB will be hidden TI1,TD1, PB2, TI2, TD2, CYC1, CYC2, OFST, CPB and DB will be hidden
and have no function to the system. The auto-tuning mode and bumpless and have no function to the system. The auto-tuning mode and bumpless
transfer will be disabled too. transfer will be disabled too.
Heat only P ( or PD ) control : Heat only P ( or PD ) control :
TI1 and TI2 to ZERO, OFST is used to adjust the control offset ( manual TI1 and TI2 to ZERO, OFST is used to adjust the control offset ( manual
reset ). reset ). O1HY is hidden. O1HY is hidden.
range 0 - 100.0 %. In the steady state ( ie. the process has been stabilized ) range 0 - 100.0 %. In the steady state ( ie. the process has been stabilized )
if the process value is lower than the set point by a definite value, say 5 C, if the process value is lower than the set point by a definite value, say 5 C,
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while 20 C is used for proportional band, that is lower than set point by while 20 C is used for proportional band, that is lower than set point by
25 %, then increase OFST value by 25 % will compensate the process 25 %, then increase OFST value by 25 % will compensate the process
ofset situation. After adjusting OFST to a correct value, the process value ofset situation. After adjusting OFST to a correct value, the process value
will move to coincide with set point. The auto-tuning mode is disabled for will move to coincide with set point. The auto-tuning mode is disabled for
P or PD control. Refer to section 3-11 for manual tuning. P or PD control P or PD control. Refer to section 3-11 for manual tuning. P or PD control
is not prefect because the load may change from time to time and you is not prefect because the load may change from time to time and you
need to adjust OFST often. The PID control can avoid this defect. need to adjust OFST often. The PID control can avoid this defect.
Select Select
OFST Function : OFST Function :
UM0P411A
Dead band = O1HY
Time
Time
or or for OUT1 and set for OUT1 and set
OFST is measured by % with OFST is measured by % with
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