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26
SOUND VELOCITIES IN DIFFERENT GASES
The following table contains the sound velocity of various gases measured on
20°C
.
Gases
Sound Velocity (m/s)
Acetaldehyde
C
2
H
4
O
252.8
Acetylene
C
2
H
2
340.8
Ammonia
NH
3
429.9
Argon
Ar
319.1
Bensol
C
6
H
6
183.4
Carbon dioxide
CO
2
268.3
Carbon monoxide
CO
349.2
Carbon tetrachloride
CCl
4
150.2
Chlorine
Cl
2
212.7
Dimethyl ether
CH
3
OCH
3
213.4
Ethane
C
2
H
6
327.4
Ethanol
C
2
H
3
OH
267.3
Ethylene
C
2
H
4
329.4
Helium
He
994.5
Hydrogen sulphide
H
2
S
321.1
Methane
CH
4
445.5
Methanol
CH
3
OH
347
Neon
Ne
449.6
Nitrogen
N
2
349.1
Nitrogen monoxide
NO
346
Oxygen
O
2
328.6
Propane
N.A.
C
3
H
8
246.5
Sulphur hexafluoride
SF
6
137.8
Par.
Page
Description
Par.
Page
Description
P00
12
Application/Engineering Units
P25
18
Selection of Echo in the measuring
window
P01
13
Measurement Mode
P26
18
Level elevation rate (filling speed)
P02
13
Calculation units
P27
18
Level descent rate (emptying speed)
P03
13
Values Displayed-Rounding
P28
18
Echo-loss handling
P04
14
Maximum measuring distance
P29
18
Blocking out of object #1
P05
15
Minimum measuring dist. (Close-end
blocking)
P30
18
Blocking out of object #2
P06
15
Far-end blocking
P31
19
Sound velocity at 20
_
C
P07
N.A.
P32
19
Specific gravity
P08
N.A.
P33
19
Manual echo selection
P09
N.A.
P34
N.A.
P10
16
Value assigned to 4 mA current output
P35
N.A.
P11
16
Value to 20 mA current output
P36
N.A.
P12
16
Error indication by the current output
P37
N.A.
P13
16
Relay function
P38
N.A.
P14
16
Relay parameter – Setpoint value
P39
N.A.
P15
16
Relay parameter – Setpoint value
P40
20/40
Tank/silo shape / Appliances, formula,
data
P16
16
Relay parameter – Pulse rate
P41
20/40
Tank/silo dimensions / Flume/weir
dimensions
P17
N.A.
P42
20/40
Tank/silo dimensions / Flume/weir
dimensions
P18
N.A.
P43
20/40
Tank/silo dimensions / Flume/weir
dimensions
P19
N.A.
P44
20/40
Tank/silo dimensions / Flume/weir
dimensions
P20
Damping
P45
20/40
Tank/silo dimensions / Flume/weir
dimensions
P21
N.A.
P46
21
Dist. btw. transducer face and level of
Q=0
P22
17
Dome top tank compensation
P47
23
Linearisation
P23
17
Angle of repos (only for free flowing
solids)
P48
23
Linearisation table
P24
17
Target tracking speed
P49
N.A.