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Gas compensation, Absolute pressure and temperature, Gas compensation 21 – Badger Meter B3000 User Manual

Page 21: Absolute pressure and temperature 21, P v t = p v t

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Programming Manual

Page 21

March 2014

GAS COMPENSATION

Gas Turbines Only
Fluid measured by the gas turbine meter is compressible, and is also affected by temperature changes and pressure changes

as illustrated by the ideal gas law equation

P V

T

=

P V

T

1 1

1

2 2

2

Absolute Pressure and Temperature

The ideal gas law equation shows that the volume of gas is determined by pressure and temperature applied to the gas under

running conditions In this equation, the pressure, P, is absolute pressure the observed gauge pressure plus the atmospheric

pressure The commonly used domestic unit of measure for absolute pressure is pounds per square inch absolute (psia)

Atmospheric pressure is considered to be 14 73 psi Therefore, absolute pressure (psia) is the sum of the gage

pressure plus 14 73
The absolute temperature in the equation above is expressed in degrees Rankine, which is calculated by adding 459 67 to the

temperature in ° F
Because pressure and temperature have a large impact on the mass of gas moving through the flow meter both values must

be entered into the B3000 for accurate gas readings to occur

OTE:

N

The B3000 calculates the correct pressure and temperature values without having to convert to absolute pressure or

degrees Rankine The compensation values should be entered in psig and ° F

Operating Pressure Op Pres
Basic Function (Gas Only)
At the Op Pres prompt, press ENTER The first digit of the current pressure setting begins to flash
If the current selection requires a change, use

▲ to increment the display digit until it matches the first digit of the required

pressure value Next press

► to advance to the next digit and using ▲ to increment the second display digit until it matches

the second digit of the operating pressure When the correct pressure setting has been entered, press ENTER to save the new

pressure value
Operating Temperature Op Temp
Basic Function (Gas Only)
At the Op Temp prompt, press ENTER The first digit of the current temperature setting begins to flash
If the current selection requires a change, use

▲ to increment the display digit until it matches the first digit of the required

temperature value Next press

► to advance to the next digit and using ▲ to increment the second display digit until it

matches the second digit of the operating temperature When the correct pressure setting has been entered, press ENTER to

save the new temperature value
Damping Factor Damping
Extended Function
The damping factor is increased to enhance the stability of the flow readings Damping values are decreased to allow the

monitor to react faster to changing values of flow This parameter can take on any value between 0…99 % with 0 being

the default
At the Damping prompt, press ENTER The current damping setting will begin to flash If the current selection is correct, press

ENTER to advance to the next parameter
If the current selection requires a change, use

▲ to increment the display digit until it matches the first digit of the required

damping value Next press the

► arrow key to advance to the next digit and using ▲to increment the second display digit

until it matches the second digit of the damping value Press ENTER to save the new damping value