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0 is used to adjust the control offset (manual reset). Adjust CYC1 according to the output 1 type (O1TY).
Generally, CYC1= 0.5 ~ 2 sec for SSRD and SSR, CYC1=10 ~ 20 sec for relay output .CYC1 is ignored if
linear output is selected for O1TY. If PB1 is not equal to 0.
OFST is measured by % with range 0 - 100.0 %. In the steady state ( i.e. process has been
stabilized ) if the process value is lower than the set point a definite value, say 5 C, while 20 C is used for
PB1, that is lower 25 %, then increase OFST 25 %, and vice versa. After adjusting OFST value, the process
value will be varied and eventually, coincide with set point.
Using the P control (TI1 set to 0), the auto-tuning and self-tuning are disabled. Manual reset
(adjust OFST) is not practical because the load may change from time to time and often need to adjust
OFST repeatedly. The PID control can avoid this situation. Selecting REVR for OUT1, SP1 is used to adjust
set point value.
TIME is used to adjust the dwell timer (enabled by selecting TIMR for A1FN or A2FN). PB1 and
TI1 should not be zero. Adjust CYC1 according to the output 1 type (O1TY). Generally, CYC1 = 0.5 ~ 2 sec
for SSRD and SSR, CYC1 = 10 ~ 20 sec for relay output. CYC1 is ignored if linear output is selected for
O1TY.
In most cases the self-tuning can be used to substitute the auto-tuning. See If self-tuning is not
used (select NONE for SELF), then use auto-tuning for the new process, or set PB1, TI1 and TD1 with
historical values. If the control result is still unsatisfactory, then use manual tuning to improve the control.
This Process Control Card contains a very clever PID and Fuzzy algorithm to achieve a very small
overshoot and very quick response to the process if it is properly tuned.
5.2.4.2 Cool Only ON-OFF Control
ON-OFF control, P (PD) control and PID control can be used for cool control. Set OUT1 to DIRT
(direct action). The other functions for cool only ON-OFF control, cool only P(PD) control and cool only PID
control are same as Heat only ON-OFF Control except that the output variable (and action ) for the cool
control is inverse to the heat control, such as the following diagram shows:
5.2.4.3 Heat Cool Control
The Heat-Cool Control can use one of 6 combinations of control modes. Setups of Parameters
for each control mode are shown in the following table.
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