FMC Technologies Proline Promass 83 E - Function Description

Issue/Rev. 0.2 (12/12)
Page 150 • MN0M023
10 Block SPECIAL FUNCTION Device Functions Proline Promass 83
COMPENSATION MODE
(continued)
• Response when MODE 2 is selected:
For batchings where batching accuracy is vital and where process-related fluctuations
in flow occur during after running. Batching ends before the quantity specified in the
function BATCH QUANTITY (7203) is achieved and the after run quantity is recorded.
The exact batching switch-off time is calculated based on the previous after run
quantities.
The number of after run quantities which are to influence the calculation can be
specified in the functions AVERAGING DRIP (7207) and CALCULATION MODE
(7206). The after run quantity in MODE 2 is determined between the switch-off point
and the constant undershooting of the low-flow cut off. This means that the lower the
setting is for the low-flow cut off, the longer the after run quantity is recorded. The
batching is very accurate.
Example diagram of a batching sequence and the respective response in MODE 1 and
MODE 2:
A0004711
Q = Flow
t = Time
t
1
= time period shorter than or equal to the maximum batching time
A = Coarse batching quantity
B = Fine batching quantity
C = After run quantity
(Effective batching quantity = A + B + C)
1 = Coarse batching starts and valve 2 opens (two-stage batching)
2 = Coarse batching ends / fine batching starts, valve 2 closes, valve 1 opens
3 = Fine batching ends, valve 1 closes (automatically when the specified batching quantity is
achieved)
4 = After run quantity recording in MODE 1 ends
5 = After run quantity recording in MODE 2 ends
a = After run quantity recorded in MODE 1
b = After run quantity recorded in MODE 2
s = Low flow cut off
Function description
SPECIAL FUNCTION o BATCHING FUNCTION o CONFIGURATION
t
Q
A
t
1
B
a
s
12345
b
C