CD600 Plus - User's Manual
4.52
)3 (
] pulse
] vol ofunits [
=
[Hz]f
] vol ofunits [
q
V
= FSV
[
)4 ( f . FSV =
q
V
Thus,
The CD600 combines equations (2) and (4), allowing the use of both factors with no need for
additional calculations:
) 5 ( f .
FTR
FSV
=
q
V
Should the factor be given in [pulses/unit volume], the FTR value shall be adjusted in parameter
AFTR and FSV shall be equal to 1 in parameter AFSV.
If, otherwise, the factor is given in [units of volume /pulse], FSV is adjusted in AFSV and it is
necessary to make
FTR=1 in AFTR.
INSTANTANEOUS FLOW INDICATION (AMFL)
When the block is selected as a pulse input, output 91/95 provide a signal Q which varies from 0 to
100% proportionally to the flow rate in accordance with the following equation:
)6 ( ] % [100 .
MFL
q
V
= Q
Where, MFL is the frequency for the highest expected flow rate. MFL shall be adjusted in parameter
AMFL.
TOTALIZATION FACTOR (AFE)
This factor determines the number of units of volume or mass corresponding to one totalization unit.
If AFE=10, there will be one totalization increment every 10 engineering units of volume.
CORRECTION BY DENSITY (AZDN and AMDN)
Flow rate may be totalized in volume or in volume corrected by the density, which corresponds to
mass flow or volume at reference conditions.
Density, which may be calculated by the flow correction block or by the polynomial, is linked to input
A. Input value, which varies from 0% to 100%, is transformed in engineering units by parameters
AZDN and AMDN.
The density value multiplies the pulses rate, thus implementing the correction for density variation.
NUMBER OF PULSES FOR CALCULATION (APLS)
This is the maximum number of pulses processed per controller processing cycle. This value is
applied to optimize the microprocessor time distribution. Larger numbers should be applied for large
flows.
APLS=fmax . t
cycle
fmax = highest expected input frequency
t
cycle
= controller cycle time
COUNTING LIMIT
Notice that, as in Function 18, the maximum number of countings sent to the counter in one cycle is
120. The exceeding pulses are stored to be unloaded later. In order to avoid this problem keep:
120 < ) time cycle x(
AFE
AMFL
CLEAR TOTALIZER
A high logic level at input
C clears the totalizers and keeps them at zero value while present.
The totalizer outputs TOT
V
(Total Volume) and TOT
n
(Total mass) are 8 digit numbers available only for
input G of the Front View blocks. See block F18 - Totalization for more details on these outputs.
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