LIQUI-FLOW series L300 pages
LIQUI-FLOW
TM
Series L30 Digital Mass Flow Meters / Controllers for Liquids
> Introduction
Bronkhorst High-Tech B.V., the European market leader in thermal
Mass Flow Meters/Controllers and Electronic Pressure Controllers,
has many years experience in designing and manufacturing precise
and reliable measurement and control devices. With a wide range
of instruments, Bronkhorst High-Tech offers innovative solutions for
many different applications in many different markets. The
instruments are made to customers’ specification, in various styles,
suitable for use in laboratory, industrial environment, hazardous
areas, semiconductor processing or analytical equipment.
> LIQUI-FLOW series L30
TM
Bronkhorst High-Tech B.V. has been the pioneer in the field of
micro to low flow liquid metering instruments based on a thermal
measuring principle. The L30 digital LIQUI-FLOW Mass Flow
Meter was designed to cover the range between 2 and 20 kg/h
(Full Scale) to expand from the product line of liquid flow meters/
controllers with ranges down to 75 mg/h FS.
The L30 Mass Flow Meter is essentially a straight tube of 316L
stainless steel with a unique thin film thermopile sensor/heater
design, fixed to the outside of the tube. The sensor signal is
obtained by measuring the power needed to maintain a constant
temperature rise of the fluid. In a formula this can be expressed
as follows:
tt
Power
= k . cp . Φm
Signal output =
tt
ΔT
TM
> Multi-Bus technology
Bronkhorst High-Tech developed their latest digital instruments
according to the “multi-bus” principle. The basic pc-board on the
instrument contains all of the general functions needed for measurement and control. It has analog I/O-signals and also an RS232
connection as a standard feature. In addition there is the possibility
of integrating an interface board with DeviceNet™, PROFIBUS DP,
Modbus-RTU or FLOW-BUS protocol. The latter is a fieldbus based
on RS485, specifically designed by Bronkhorst High-Tech for their
mass flow metering and control solutions, and through which the
company already has over ten years of experience with digital
communication.
> General features LIQUI-FLOW series L30
TM
utno moving parts
utthru-flow measurement
utcompact control loop with control valve or pump
utsuitable for liquids with low boiling points
utall metal seals
> Digital features
utDeviceNetTM, PROFIBUS DP, Modbus-RTU or
FLOW-BUS slave
ΔTt= temperature differencet
kt = meter constantt
cpt = specific heat
Φmt = mass flow
> Liquid flow control
Flow control is achieved by integrating a control valve onto the
body of the Liquid Flow Meter. This control valve has a purge
connection on top of the sleeve that enables easy elimination of
air or gas when starting up the system. The electronic control
function forms part of the normal circuitry in the liquid flow meter,
so the need for an external controller is eliminated.
utRS232 interface
ut ther fieldbus options on request
o
ut larm and counter functions
a
> Fields of application
utSemiconductor industry
utChemical industry
utFood & Pharmaceutical industry
utPackaging production and treatment
utAnalytical laboratories