Emerson Daniel 3410 Series Operation Manual page 31

Operations manual
DAN-20057316
If all chords fail, then the meter re-enters the Acquisition mode as described in the
acquisition
The meter partitions the velocity range (for forward and reverse flow) into ten
consecutive, non- overlapping "bins" (where the velocity range is as specified via the
MeterMaxVel data point).
The meter maintains a set of bins for each active chord where each bin contain three data
values: (1) the chord's average velocity (within the bin's velocity range), (2) the chord's
average proportion value, and (3) an indicator that the value is still the default (Is[Fwd/
Rev]Prop[A..H]DfltBin[1..10]). A chord proportion value is the ratio of the chord velocity
to the average weighted flow velocity as shown in
indicator is used to determine if a bin's velocity and proportion data values have been
updated from their initialized values. The bins are initialized with the average velocity over
the bin's range and meter-geometry-dependent proportion values. All default indicators
are initialized to TRUE. The bin data is stored in non-volatile memory.
Equation 4-5: Chord proportion calculation
where
Prop
V
V
When the meter has operated for a user-specified number of consecutive batches without
any chord failures, the meter updates each chord's data values for the bin containing the
chord velocity as shown in
PropUpdtBatches data point, configurable via the Daniel MeterLink Edit/Compare
Configuration screen, specifies the number of consecutive failure-free batches required
for updating the bin data (range: [1, 1000], default: 24). The NumVals data point (that
determines how quickly an average value changes) is also configurable via the Edit/
Compare Configuration screen (range: [1, 1000], default: 10).
Equation 4-6: Updating chord proportion bin data values
where
AvgVel
AvgVel
NumVals = update factor data point (dimensionless) (NumVals)
V
AvgProp
AvgVel
Prop
Model 3418 GUSM
section.
= chord proportion (dimensionless)
chord
= chord velocity (m/s) (FlowVelA ... FlowVelH)
chord
= average weighted gas flow velocity (m/s) (AvgWtdFlowVel)
AvgWtd
Equation 4-6
AvgVel
CℎordBin n + 1
AvgProp
CℎordBin n + 1
= chord bin (n+1)st average velocity (m/s)
ChordBin
n+1
= chord bin nth average velocity (m/s)
ChordBin
n
= chord velocity (m/s) (FlowVelA ... FlowVelH)
chord
= chord bin (n+1)st average proportion value (dimensionless)
ChordBin
n+1
= chord bin nth average proportion value (dimensionless)
ChordBin
n
= chord proportion (dimensionless)
chord
Equation 4-5
V cℎord
Prop −
cℎord
V AvgWtd
and sets the bin's default indicator to FALSE. The
AvgVel CℎordBin ⋅ NumVals − 1
−
n
NumVals
AvgProp CℎordBin ⋅ NumVals − 1
−
n
NumVals
Measurement
January 2019
Re-
below. The default
+ V cℎord
+ Prop cℎord
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