Emerson Fisher FIELDVUE DVC6000f Instruction Manual page 165

START
No
OP_SELECT
equal to zero?
Yes
Yes
SELECT_TYPE
Average?
No
Yes
SELECT_TYPE
Middle?
No
Yes
SELECT_TYPE
Maximum?
No
Yes
SELECT_TYPE
Minimum?
No
Yes
SELECT_TYPE
First Good or Hot
Spare?
No
Illegal Select Type
should never be reached
NOTES:
LIMIT MANIPULATION FOR A CONSTANT INPUT FOR MAXIMUM AND MINIMUM IS BASED UPON THE FOUNDATION FIELDBUS SPECIFICATION.
1
THE REASONING IS BASED ON HIGH SELECT PROVIDING A LOW LIMIT STATUS AND LOW SELECT PROVIDING A HIGH LIMIT STATUS.
December 2009
All inputs with
same limit
status?
No
Propagate
Not Limited
Yes All inputs with
More than 1
same limit
input?
status?
No
No
Propagate
Not Limited
Input a Yes
constant?
No
Propagate
Input a Yes
Low Limit
constant?
No
Yes
Input a Propagate
High Limit
constant?
No
Figure 4-15. Input Selector Block Limit Propagation
ISEL Function Block
Propagate
selected input
limit status
Yes
Propagate that
Yes
limit status
Propagate
Constant
1
1
Propagate
selected input
limit status
4
4-105