FloBoss 103/104 Instruction Manual
Revised August-2017
Pulse Interface Module
7-1
Chapter 7
– Pulse Interface Module
In This Chapter
Pulse Interface Module .................................................................... 7-1
Making Process Connections ............................................... 7-3
Configuring the Pulse Interface Module ............................... 7-3
This chapter describes the Pulse Interface module, which provides
pressure inputs and pulses counts to the FloBoss 104 for AGA7 flow
calculation with AGA8 compressibility. The Pulse Interface module is
intended for applications with rotary meters and turbine meters.
7.1 Pulse Interface Module
The primary function of the FB104 (see
Figure 7-1
) is to measure the
flow of natural gas using turbine metering or rotary metering in
accordance with the American Gas Association (AGA) and American
Petroleum Institute (API) standards. When performing AGA7
calculations, the FB104 uses 1992 AGA8 compressibility.
The Pulse Interface module consists of two parts: a pulse counter
interface and a pressure transducer.
▪
When used with a rotary meter, the Pulse Interface Module creates
and measures electrical signals (pulses) from the rotary meter and
raw pressure inputs from the pressure transducer. The module
automatically interprets the direction of rotation. The module has a
resolution of 1000 pulses per revolution.
▪
When used with a turbine input, the pressure is measured by the
pressure transducer and pulses from the turbine meter are measured
by the Pulse Input on the optional I/O board.
The Pulse Interface module makes the readings available to the
processor board. The pressure inputs are read from an analog input,
while the pulse counts are read as a pulse input.
The primary inputs used for AGA7 flow measurement are Pulse Input
(PI) counts, static pressure, and temperature. A rotary meter or turbine
meter provides the pulse input counts, pressure transducers provide
static pressure (including auxiliary pressure) inputs, and an RTD probe
provides the temperature input. After the static pressure and auxiliary
pressure values are read, the flowing temperature is read. The FB104
processor reads inputs at the following rates:
•
Pulse counts are read from the Pulse Interface module once per
second.
