Brainchild P91 User Manual

SP1
SP1 O1HY
ON
OFF
Output 1 Action
PV
Dead band = O1HY
Time
Time
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
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
and have no function to the system. The auto-tuning mode and bumpless
transfer will be disabled too.
Select or for OUT1 and set
TI1 and TI2 to ZERO, OFST is used to adjust the control offset ( manual
reset ). OFST is measured by % with
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,
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
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
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
need to adjust OFST often. The PID control can avoid this defect.
Heat onlyP(orPD)control :
OFST Function :O1HY is hidden.
L
L
The ON-OFF control may introduce excessive process oscillation even
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
and
have no function to the system. The auto-tuning mode and bumpless
transfer
will be disabled too.
Select
or for OUT1 and set
TI1
and TI2 to ZERO, OFST is used to adjust the control offset ( manual
reset
). OFST is measured by % with
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 5C,
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
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
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
need
to adjust OFST often. The PID control can avoid this defect.
Heat
only P ( or PD ) control :
OFST
Function :O1HY is hidden.
L
L
UM0P411A
47

Brainchild P91 Specifications

General

Brand	Brainchild
Model	P91
Category	Controller
Language	English