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4-117
Chapter 4. Functions
Item (bank)
Display
Description
Initial value
R value scale
(Health index bank)
MENU > HealthIndex
R value scale
0 to 10
4
Ideal data
(Health index bank)
MENU > HealthIndex
Best data
0.0000 to 32000
0.0000
Deviation low limit
(Health index bank)
MENU > HealthIndex
Deviation
low limit
0.0000 to 32000
No low limit when 0.0000
0.0000
Deviation high limit
(Health index bank)
MENU > HealthIndex
Deviation
high limit
0.0000 to 32000
No high limit when 0.0000
0.0000
SP high limit
(SP configuration bank)
MENU > SP Config
SP high limit
−32000 to +32000
32000
Handling Precautions
•
The R value scale is the power of 10 by which to multiply the R value. For
example, "4" means 10 to the fourth power, that is, multiplied by 10000. The
range of R value varies greatly depending on the characteristics of the process
to be controlled. Try to adjust the R value scale several times so that the R
value is manageable.
•
If the R value becomes too large, it is automatically limited to a 7-digit integer.
•
The SP high limit is used as a condition for determining the specific R value.
Set this value as close to the SP as possible. If the SP high limit exceeds the SP
by a large margin, the specific R value cannot be determined. Therefore, the
value remains set at the initial value of 0.0.
•
If the operation type has been set to DI1 or DI2, set the operation type of the
applicable DI/DO to DI in the DI/DO bank.
z
Operation
The R value is calculated when the DI or event selected for the operation type is
ON.
The R value is not calculated if the DI or event selected for the operation type is
OFF, or if "0: Stop" is selected for the operation type.
Handling Precautions
•
The health index's function is to calculate the R value and the specific R
value only, so it does not affect PID control.
•
Depending on the control status, the specific R value may not be
identified correctly. Especially before and after a batch process, since the
response to the MV is not reflected in the PV, the R value often becomes
abnormal, which adversely affects the definition of the R value. For this
reason, be sure to start the health index function after a batch process
starts and the PV begins to change.