horiba SF-1U, Instruction Manual

Page: 37 / 60

E-2
1. Outline
A measuring unit (VP series) is connected to this series of FILM FLOW METER to measure
the flow rate of various gases. The measuring unit consists of a precision measuring tube and
a soap water film detector. It measures flow rates by detecting the soap water film that
passes through the measuring tube. Entering the calibration temperature and integrating a
high precision barometer (SF-2U), measured flow rates are corrected and generated
automatically.
2. Principles
Pressing the start key starts the pulse motor and activates the film ring. When the gas flows,
a soap water film formed at the mouth of the measuring tube by the film ring will move up in
the measuring tube. The measuring tube is calibrated to a high precision. The equipment
calculates the flow rate when it measures the time of the soap film moving over the distance
between the start and stop detection points. In addition, the microcomputer processes the
temperature and atmospheric pressure to correct the measured flow rate by the vapor
pressure to indicate the flow rate at the calibrated temperature (0 to 35
℃
) at standard
atmospheric pressure of 1013.3 hPa.
Fig.1 Principles
3. Checking the Accessories

Equipment body SF-1U or SF-2U x1

Filming liquid Snoop
®
59ml x1

Instruction manual I030248700 x1
※
Separately, a dedicated AC adapter set is required.
Temp.
sensor
Volume
data
Pulse
motor
Film ring
Measuring
tube
Measuring
unit
Filming liquid
Gas inlet
Gas outlet
Microcomputer
Atmospheric
pressure sensor
Vapor pressure
Approximate expression
Start
Display
Stop
detector
Start
detector
Equipment
body