Calculation Of The Volume At Base Conditions; Totalizers; Overview - RMG EC 900 Operating Instructions Manual

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Calculation of the volume at base conditions

The volume at base conditions is calculated from the volume at measurement conditions, pressure,
temperature and compressibility in accordance with the following equation:
where
V volume at measurement conditions
m
V volume at base conditions
b
P pressure at measurement conditions [bar]
P pressure at base conditions
b
t temperature
t temperature at base conditions
b
K K coefficient
Z /Z Compressibility factors
m b
In Germany, the pressure at base conditions is legally fixed at 1.01325 bar and the temperature at
base conditions at 273.15 K (= 0°C).
The following methods are available for calculating the K coefficient:
GERG 88S, AGA-NX-19, AGA-NX-19 corr. and AGA Gross 1 for natural gas.

Totalizers

Overview

The EC 900 has three types of volume totalizers:
Totalizer for the original volume at measurement conditions V
Totalizers for the volume at measurement conditions V
Totalizers for the volume at base conditions V
The V totalizer either shows the original reading of the encoder index or is supplied in parallel to
o
the basic totalizer for the volume at measurement conditions V
LF or HF input. Furthermore, the V
differs from the V
index or can be set in the case of the LF input and that the totalizer continues to run if there is a
fault.
The volume at base conditions can be calculated on the basis of either V
lect the method to be used. V
actually been connected to this totalizer, but not if an original reading is simulated via an LF input.
If Vo is used for the formation of Vb, the Vm totalizer will add up the increments from one Vo read-
ing to the next Vo reading.
In compliance with MID, the Vm totalizer continues to run if there is a fault. The Vm disturbance
totalizer runs as long as there is a fault. Then only the V
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;
totalizer can also be operated as a copy of the V
o
totalizer in that its reading automatically accepts the value from the encoder
m
may only be used for the formation of V
o
CONSTRUCTION AND FUNCTION
[m³]
These are the international desig-
[m³]
nations as per EN 12405. Alterna-
tively, you can also use the indices
[bar]
"b" for quantities at measurement
[°C]
conditions and "n" for quantities at
[°C]
[1]
[1]
o
and V
m mD
and V
b bD
as an accumulative totalizer via an
m
b
totalizer can be stopped via a fault mode.
b
totalizer. It
m
or V . The user can se-
m o
if an encoder index has
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