KEP ES749 - Page 112

ES749 Flow Computer
108
Full Scale
The value of the process variable at the full scale or maximum input signal.
Inlet Pipe Bore
The internal pipe diameter upstream of the ow measurement element.
Isentropic Exponent
A property of a gas or vapor utilized in orice meter calculations.
K-Factor
The calibration constant for a pulse producing owmeter expressed in pulses per unit volume
Linear
A ow measurement device where the output signal is proportional to ow.
Linear 16 Pt.
A mathematical approximation to a nonlinear device where by a correction factor or K-Factor table as a function of input signal
is utilized to eliminate owmeter nonlinearity.
Low Flow Cutoff
The value of input signal below which ow rate may be assumed to be 0 and at which totalization will cease.
Low Scale
The value of the process variable at the zero input signal.
Manual
An entry value to be used as a xed condition in a equation
Meter Exp. Coef.
A coefcient in an equation which may be used to correct for changes in owmeter housing dimensioned changes with
temperature.
Mole %
The % composition of an individual gas in a gas mixture.
NX-19
A series of equations used to compute the compressibility of natural gas as a function of specic gravity, temperature,
pressure and gas composition.
Protocol
An agreed upon method of information exchange.
Print Initiate
A user specied condition which must be satised for a transaction document to be printed.
Pulse Type
A menu selectable equivalent pulse output stage.
Pulse Value
An output scaling factor dening the equivalent amount of ow total represented by 1 output pulse.
Ref. Z-Factor
The Z-Factor for a gas at reference conditions of temperature and pressure.
Ref. Density
The density of a uid at reference conditions of temperature and pressure.
Relay Function
The assigned usage for a relay output.
Relay Mode
The user’s desired operating mode for the relay. Examples: follow, latch, timed pulse, above setpoint, below setpoint
Safe State
The state of an instrument's outputs which will occur during a power down state. The state the instrument assumes when the
computations are paused.
11. Glossary of Terms (Continued)