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Chapter 4. Functions
The health Index is a function that uses our proprietary process-data processing technology to convert the process
status to numerical values. The CDS (compact data storage) can be used to store the health index on a microSD
memory card.
The health index includes the following elements.
•
R value
•
Specific R value
z
R value
The R value for each sampling cycle is calculated using the process gain (Kp) and
delay (Tp) obtained from PID control calculation and the referencing of models.
R = Kp/Tp
To use R as a health index, start the CDS function at the start of a batch process,
and stop the CDS function at the end of the batch process. An R value that
represents the characteristics of the process is specified for one batch process. This
is called the specific R value.
By comparing the specific R value that was determined when the process was
healthy with the current specific R value, it may be possible to predict equipment
failure.
z
Settings
Health index operation can be set for each control loop.
Item (bank)
Display
Description
Initial value
Operation type
(Health index bank)
MENU > HealthIndex
Operation type
0: Stop
1: DI1 status
2: DI2 status
3 to 10: Reserved
11: Event 1
12: Event 2
13: Event 3
14: Event 4
15: Event 5
16: Event 6
17: Event 7
18: Event 8
19: Event 9
20: Event 10
21: Event 11
22: Event 12
23: Event 13
24: Event 14
25: Event 15
26: Event 16
27 to 1023: Reserved
1024 to 2047: Standard bits
14 - 2 Standard Bit Codes and Standard
0
4 - 20 Health Index