Instruction Manual

Instruction Manual
D103412X012
Detailed Setup—ISEL Function Block
January 2015
124
Figure 4‐14. Input Selector Block Limit Propagation
START
SELECT_TYPE
Middle?
Yes
No
SELECT_TYPE
Maximum?
SELECT_TYPE
Minimum?
More than 1
input?
Yes
All inputs with
same limit
status?
Yes
Propagate that
limit status
Input a
constant?
Propagate
Not Limited
No
Propagate
Constant
No
Yes
No
Yes
No
Input a
constant?
Propagate
Low Limit
Propagate
High Limit
Input a
constant?
Yes
SELECT_TYPE
First Good or Hot
Spare?
No
No
No
SELECT_TYPE
Average?
All inputs with
same limit
status?
Propagate
Not Limited
Yes
Yes
No
No
1
1
NOTES:
 LIMIT MANIPULATION FOR A CONSTANT INPUT FOR MAXIMUM AND MINIMUM IS BASED
UPON THE FOUNDATION FIELDBUS SPECIFICATION. THE REASONING IS BASED ON HIGH SELECT
PROVIDING A LOW LIMIT STATUS AND LOW SELECT PROVIDING A HIGH LIMIT STATUS.
1
Yes
Yes
Propagate
selected input
limit status
OP_SELECT
equal to zero?
Yes
No
Propagate
selected input
limit status
No
Yes
Illegal Select Type
should never be reached