Low-Flow Ultrasonic Flow Meter for Liquids

  • Fast and accurate measuring signal
  • Low pressure loss due to straight sensor tube
  • Medium independent and temperature insensitive
  • Hygienic design, display with capacitive touchscreen
  • IP67 rating and CIP cleanable
  • Flanged connection


Get a quote Downloads Support

Low-Flow Ultrasonic Flow Meters for Liquids

ES-FLOW™ model ES-103I Liquid Flow Meters (LFMs) are suited for precise measurement of volume flow ranges between 4 and 1500 ml/min at operating pressures up to 10 bar. The LFM consists of a innovative ultrasonic flow sensor and an IP67 protected measuring head with bright LCD display and capacitive touchscreen for adjustment of the settings e.g. for flow indication, alarm, totalisation and control (if applicable). The electronics include a PID controller for optional flow control by means of a separately mounted control valve or pump. ES-FLOW™ model ES-103I has orbitally welded TriClamp flanges for hygienic applications.

Bronkhorst® ES-FLOW™ series are equipped with a digital pc-board, offering high accuracy, excellent temperature stability and fast response. The main digital pc-board contains all of the general functions needed for measurement and control. In addition to the standard RS232 output the instruments also offer analog I/O. As an option, an on-board interface can be mounted to provide DeviceNet™, PROFIBUS DP, Modbus or FLOW-BUS protocols.

Technical specifications

Measurement  / Control system
Minimum full scale flow 200 ml/min
Maximum full scale flow 1500 ml/min
Minimum flow 4 ml/min
Volume flow accuracy ±1% Rd ± 1 ml/min
Repeatability ≤ 0.1% Rd ± 0.05 ml/min
Turndown ratio

analog: 1:50 (2...100%);
digital 4:200 up to 4:1500 ml/min;
full scale value scalable by the user

Fluids fluid independent measurement; also suitable for non-conductive fluids
Response time  ≤200 msec (meter, t98%)
Refresh (cycle) time ≤10 msec
Ambient temperature 10…60°C
Fluid temperature accuracy ±1 °C
Attitude sensitivity negligible; mounting in any position
Warm-up time approx. 1/2 hour after power up for optimum performance
Mechanical parts
Material (wetted parts) Stainless steel 316L
Surface quality (wetted parts) Ra < 0,8 μm
Sensor Straight tube
Process connections (welded) 1/4” Triclamp flanges; other on request
Seals (internal) None

Meter: 1,3 kg;
Controller: on request

Ingress protection (housing) IP67
Pressure rating 10 bara at TAMB = 15...35°C, |TAMB - TMED| ≤ 25°C; for elevated temperatures please consult factory
Electrical properties
Power supply +15…24 Vdc ±10% Max. ripple recommended: 50 mV tt
Power consumption Max. 2.8 W
Analog output 0…5 (10) Vdc, min. load impedance > 2 kΩ; 0 (4)…20 mA (sourcing), max. load impedance < 375 Ω
Analog setpoint 0…5 (10) Vdc, min. load impedance > 100 kΩ; 0 (4)…20 mA, load impedance ~250 Ω
Customised I/O
(Pin 5 options)
Analog control signal output: 0...10 Vdc or 4...20 mA;
Pulse output
Digital communication Standard RS232; Options: PROFIBUS DP, DeviceNet, Modbus RTU/ASCII, FLOW-BUS
Electrical connections
Analog/RS232 M12 connector (male)
PROFIBUS DP bus: M12 connector (female); power: M12 connector (male)
DeviceNet 5-pin M12 connector (male)
Modbus (RTU/ASCII)/FLOW-BUS M12 connector (male)
Approvals / Certificate
Food contact EC 1935/2004
For dimensional drawings and hook-up diagrams please visit the productpage on our website


ES-FLOW brochure
ES-FLOW model key

Manual ES-FLOW

ES-FLOW Series DoC EC1935-2004

Hook-up diagrams
Analog IO - RS232
Optional Bus and IO-Configurations

Dimensional drawing
Dimensional drawing ES-103I-ES-113I

Bronkhorst High-Tech B.V.

Nijverheidsstraat 1A
NL-7261 AK Ruurlo (NL)
Tel. +31 573 45 88 00
[email protected]

Copyright © 2019 Bronkhorst. All rights reserved.     Sitemap     Disclaimer     Privacy note