Magnetrol STI Echotel 338, Инструкция по установке и эксплуатации

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51-638 Echotel Model 338 Two-Wire Ultrasonic Transmitter
2.5 Velocity of Sound in Gases other than Air
The velocity of sound through air is 1,128 ft/sec
(343.8 m/sec) as indicated in P31. This velocity is used for
all measurements made by the Model 338 transmitter. The
table below contains the velocity of sound for various gases
measured @ +68° F (+20° C). These velocities can be used
in P31 if the gas exists as a homogeneous layer in the tank.
2.6 Specifications
2.6.1 Performance
Accuracy ±(0.2% of the measured
distance, plus 0.05% of the
range)
Resolution 1 mm for up to 6.5 feet (2 m)
2 mm for 6.5 to 16.4 feet (5 m)
5 mm for 16.4 to 20 feet (6 m)
Velocity Velocity
Gases Chemical Formula (ft/sec) (m/s)
Acetaldehyde C2H4O 829.4 252.8
Acetylene C2H2 1118.2 340.8
Ammonia NH3 1410.5 429.9
Argon Ar 1047.0 319.1
Benzene C6H6 601.7 183.4
Carbon dioxide CO2 880.3 268.3
Carbon monoxide CO 1145.7 349.2
Carbon tetrachloride CCl4 492.8 150.2
Chlorine Cl2 697.9 212.7
Dimethyl ether CH3OCH3 700.2 213.4
Ethane C2H6 1074.2 327.4
Ethanol C2H3OH 877.0 267.3
Ethylene C2H4 1080.8 329.4
Helium He 3263.0 994.5
Hydrogen sulphide H2S 1053.5 321.1
Methane CH4 1461.7 445.5
Methanol CH3OH 1138.5 347
Neon Ne 1475.1 449.6
Nitrogen N2 1145.4 349.1
Nitrous oxide N2O 1135.2 346
Oxygen O2 1078.1 328.6
Propane C3H8 808.8 246.5
Sulfur hexafluoride SF6 452.1 137.8