BRONKHORST u-FLOW Series User manual

Instruction Manual
µ-FLOW & LIQUI-FLOW series
Thermal Mass Flow Meters/Controllers for liquids
Doc. no.: 9.17.161ADate: 18-02-2022
µ-FLOW L01(V12) LIQUI-FLOW L13(V12), L23(V12) LIQUI-FLOW L13I, L23I
ATTENTION
Please read this document carefully before installing and operating the product.
Not following the guidelines could result in personal injury and/or damage to the equipment.

______________________________________ Bronkhorst ® ______________________________________
________________________________________________________________________________________________
9.17.161 µ-FLOW & LIQUI-FLOW Instruction Manual L01, L13(I), L23(I), L13V12, L23V12
Page 2 of 50
Copyright
© 2022 Bronkhorst High-Tech B.V.
All rights reserved. No part of this publication may be reproduced, distributed, or transmitted in any form or by any means,
without the prior written permission of the publisher.
Disclaimer
This document has been reviewed and is believed to be accurate. Bronkhorst High-Tech B.V. does not assume liability
for errors, inaccuracies or absence of information. The material in this document merely serves information and illustration
purposes; no rights can be derived from its contents.
Bronkhorst High-Tech B.V. reserves the right to modify or improve its products and documentation without informing
anyone. As such, the information contained in this document is subject to change without notice. Device specifications
and the contents of the package may deviate from what is stated in this document.
Symbols in this document
Receipt of equipment
Check the outside packaging box for damage incurred during shipment. If the box is damaged, the local carrier must be
notified at once regarding his liability. At the same time a report should be submitted to your Bronkhorst representative.
Carefully remove the equipment from the box. Verify that the contents of the package was not damaged during shipment.
Should the equipment be damaged, the local carrier must be notified at once regarding his liability. At the same time a
report should be submitted to your Bronkhorst representative.
Refer to Removal and return instructions about return shipment procedures.
Equipment storage
•The equipment should be stored in its original package in a climate controlled storage location.
•Care should be taken not to subject the equipment to excessive temperatures or humidity.
•See technical specifications for information about required storage conditions.
Important information. Disregarding this information could increase the risk of damage to the
equipment, or the risk of personal injuries.
Helpful information. This information will facilitate the use of the instrument and/or contribute to its
optimal performance.
Additional information available on the internet or from your Bronkhorst representative.
•Check the packing list to ensure that you received all of the items included in the scope of delivery
•Do not discard spare or replacement parts with the packaging material

______________________________________ Bronkhorst ® ______________________________________
________________________________________________________________________________________________
9.17.161 µ-FLOW & LIQUI-FLOW Instruction Manual L01, L13(I), L23(I), L13V12, L23V12
Page 3 of 50
Warranty
Bronkhorst® products are warranted against defects in material and workmanship for a period of three years from the
date of shipment, provided they are used in accordance with the ordering specifications and not subject to abuse or
physical damage. Products that do not operate properly during this period may be repaired or replaced at no charge.
Repairs are normally warranted for one year or the balance of the original warranty, whichever is the longer.
The warranty includes all initial and latent defects, random failures, and indeterminable internal causes. It excludes failures
and damage caused by the customer, such as contamination, improper electrical hook-up, physical shock etc.
Re-conditioning of products primarily returned for warranty service that is partly or wholly judged non-warranty may be
charged for.
Bronkhorst High-Tech B.V. or affiliated company prepays outgoing freight charges when any part of the service is
performed under warranty, unless otherwise agreed upon beforehand. The costs of unstamped returns are added to the
repair invoice. Import and/or export charges as well as costs of foreign shipping methods and/or carriers are paid by the
customer.
Any liability is explicitly excluded for any secondary damage, caused by the instrument’s failure or the malfunction of
any component. All wear parts, like seals for example, are also excluded from the warranty.
All devices are provided with a seal mark upon delivery. In case of a broken seal any warranty claims are void. The
opening of the instruments is only permitted by certified service personnel authorized by the Customer Service
Department (CSD) of Bronkhorst High-Tech B.V.
The products of other manufacturers are warranted for a period of one year unless otherwise mentioned.
General safety precautions
This product is intended for use by qualified personnel who recognize shock hazards and are familiar with the safety
precautions required to avoid possible injury. Read the operating information carefully before using the product.
Before operating, make sure the line cord is connected to a properly grounded power receptacle. Inspect the connecting
cables for cracks or breaks before each use.
The equipment and accessories must be used in accordance with their specifications and operating instructions, otherwise
the safety of the equipment may be impaired.
Opening the equipment is not allowed. There are no user serviceable parts inside. In case of a defect please return the
equipment to Bronkhorst High-Tech B.V.
To maintain protection from electric shock and fire, replacement components must be obtained from Bronkhorst. Standard
fuses, with applicable national safety approvals, may be used if the rating and type are the same. Other components that
are not safety related may be obtained from other suppliers, as long as they are equivalent to the original component.
Selected parts should be obtained only through Bronkhorst, to maintain accuracy and functionality of the product. If you
are unsure about the relevance of a replacement component, contact your Bronkhorst representative for information.
See also section 9 (Guarantee) of the Conditions of sales:
www.bronkhorst.com/int/about/conditions-of-sales

______________________________________ Bronkhorst ® ______________________________________
________________________________________________________________________________________________
9.17.161 µ-FLOW & LIQUI-FLOW Instruction Manual L01, L13(I), L23(I), L13V12, L23V12
Page 4 of 50
Contents
1. Introduction ........................................................................................................................................ 7
1.1. Scope of this manual ........................................................................................................................ 7
1.2. Intended use ..................................................................................................................................... 7
1.3. Products descriptions ....................................................................................................................... 8
1.4. Product overview .............................................................................................................................. 8
1.5. Calibration......................................................................................................................................... 9
1.6. Maintenance ..................................................................................................................................... 9
1.7. Documentation ................................................................................................................................. 9
2. Product specifications .................................................................................................................... 11
2.1. Pressure rating ............................................................................................................................... 11
2.2. Model key ....................................................................................................................................... 11
2.3. Sealing material compatibility ......................................................................................................... 13
2.4. Customised I/O options .................................................................................................................. 13
3. Installation ........................................................................................................................................ 15
3.1. Mounting ......................................................................................................................................... 15
3.1.1. Orientation ................................................................................................................................ 15
3.1.2. Location in the fluid system ...................................................................................................... 15
3.1.3. Piping requirements .................................................................................................................. 15
3.1.4. Fluid connections ...................................................................................................................... 16
3.1.5. Mechanical isolation.................................................................................................................. 16
3.2. Electrical connection....................................................................................................................... 16
3.3. Fieldbus connection........................................................................................................................ 17
3.3.1. FLOW-BUS ............................................................................................................................... 17
3.3.2. Modbus ..................................................................................................................................... 17
3.3.3. Other fieldbuses........................................................................................................................ 18
4. Operation .......................................................................................................................................... 19
4.1. Powering up.................................................................................................................................... 19
4.2. First use.......................................................................................................................................... 19
4.3. Preventing slug flow ....................................................................................................................... 19
4.4. Rapid gas decompression / explosive decompression .................................................................. 19
4.5. Mass flow measurement and control.............................................................................................. 20
4.6. After use ......................................................................................................................................... 20
4.7. Powering down ............................................................................................................................... 20
4.8. Valve safe state .............................................................................................................................. 20
4.9. Temperature considerations........................................................................................................... 20
4.9.1. Preventing condensation .......................................................................................................... 21
4.9.2. Cleaning temperature ............................................................................................................... 21

______________________________________ Bronkhorst ® ______________________________________
________________________________________________________________________________________________
9.17.161 µ-FLOW & LIQUI-FLOW Instruction Manual L01, L13(I), L23(I), L13V12, L23V12
Page 5 of 50
4.10. Communication interface................................................................................................................ 21
4.10.1. Analog operation....................................................................................................................... 22
4.10.2. Digital operation ........................................................................................................................ 22
4.10.2.1. RS-232 communication ........................................................................................................ 22
4.10.2.2. Fieldbus operation ................................................................................................................ 23
4.11. Hardware interface ......................................................................................................................... 23
4.11.1. LED indications ......................................................................................................................... 23
4.11.1.1. Interface status ..................................................................................................................... 24
4.11.1.2. DeviceNet™ indications ....................................................................................................... 24
4.11.2. Multifunctional switch ................................................................................................................ 25
4.11.2.1. Normal operating functions .................................................................................................. 25
4.11.2.2. Power-up functions............................................................................................................... 26
4.11.2.3. Control mode - readout/change............................................................................................ 26
4.11.2.4. Network settings - readout/change....................................................................................... 27
4.11.3. Rotary switches......................................................................................................................... 28
4.12. Adjusting zero point ........................................................................................................................ 29
4.12.1. Manually, using multifunctional switch...................................................................................... 29
4.12.2. Digitally ..................................................................................................................................... 30
4.13. FlowDDE......................................................................................................................................... 30
4.13.1. Software (DDE applications)..................................................................................................... 31
5. Digital parameters ........................................................................................................................... 32
5.1. General ........................................................................................................................................... 32
5.2. Special parameters......................................................................................................................... 33
5.2.1. Default control mode................................................................................................................. 34
5.3. Measurement and control............................................................................................................... 34
5.3.1. Advanced measurement and control ........................................................................................ 35
5.4. Device Identification ....................................................................................................................... 36
5.5. Alarms............................................................................................................................................. 37
5.6. Counter ........................................................................................................................................... 39
5.7. Network configuration..................................................................................................................... 41
5.8. Fluid set .......................................................................................................................................... 42
5.8.1. Advanced fluid set parameters ................................................................................................. 44
5.9. Master/slave configuration (FLOW-BUS) ....................................................................................... 45
6. Troubleshooting and service.......................................................................................................... 46
6.1. Errors and warnings ....................................................................................................................... 46
6.2. Restoring factory settings ............................................................................................................... 46
6.3. Common issues.............................................................................................................................. 46
6.4. Service............................................................................................................................................ 48

______________________________________ Bronkhorst ® ______________________________________
________________________________________________________________________________________________
9.17.161 µ-FLOW & LIQUI-FLOW Instruction Manual L01, L13(I), L23(I), L13V12, L23V12
Page 6 of 50
7. Returns ............................................................................................................................................. 50
7.1. Removal and return instructions..................................................................................................... 50
7.2. Disposal (end of lifetime) ................................................................................................................ 50

______________________________________ Bronkhorst ® ______________________________________
________________________________________________________________________________________________
9.17.161 µ-FLOW & LIQUI-FLOW Instruction Manual L01, L13(I), L23(I), L13V12, L23V12
Page 7 of 50
1. Introduction
1.1. Scope of this manual
This manual covers the Bronkhorst®instrument model series µ-FLOW and LIQUI-FLOW mass flow meters/controllers
for liquid. It contains general product information, installation and operating instructions and troubleshooting tips.
µ-FLOW L01(V12);
IP40 enclosure
LIQUI-FLOW L13(V12), L23(V12);
IP40 enclosure
LIQUI-FLOW L13I, L23I;
IP65 enclosure
1.2. Intended use
The µ-FLOW L01 and LIQUI-FLOW L13(I), L23(I), L13V12, L23V12 is designed to accurately measure and/or control
liquid flow rates in a fluid system using the media and operating conditions (e.g. temperature, pressure) that were
specified at ordering time.
The liquid(s) in the pressurized system in which the instrument is mounted should preferably be clean and dry. The
equipment is suited for general purpose indoor (dry) applications, like laboratories and machine enclosures.
µ-FLOW and LIQUI-FLOW instruments are suitable for use at temperatures conditions between 5 and +50 °C and a
relative humidity of 10 to 90% RH, unless specified otherwise.
•The L01, L13, L23, L13V12 and L23V12 instruments have an ingress protection of IP40 implying that the
electronics housing and electrical connection do not offer any protection against moist environments.
•The L13I and L23I are equipped with an IP65-enclosure, so electronics housing and electrical connection are
protected against moist and dusty environments.
To avoid personal injury and/or damage to the equipment only trained and qualified personnel shall perform the
installation of the instruments.
The instruments contain electronic components which are sensitive to electronic discharges (ESD). Contact with
electronically charged persons or objects could possibly endanger these components or even result in their failure.
The wetted materials incorporated in the µ-FLOW and LIQUI-FLOW are compatible with media and
conditions (e.g. pressure, temperature) as specified at ordering time. If you are planning to use the
product (including any third party components supplied by Bronkhorst, such as pumps or valves) with
other media and/or other conditions, always check the wetted materials (including seals) for
compatibility. See the technical specifications of the product and consult third party documentation (if
applicable) to check the incorporated materials.
Responsibility for the use of the equipment with regard to suitability, intended use, cleaning and
corrosion resistance of the applied materials against the processed media lies solely with the end user.
Where appropriate, this document recommends or prescribes safety measures to be taken with
respect to media usage or working with the described equipment under the specified conditions. The
end user is responsible for taking the necessary safety precautions and proper use of appropriate
(personal) protective equipment, even if such is not explicitly recommended or required in this
document.
The end user is considered to be familiar with the necessary safety precautions, and to comply with the
appropriate protective measures as described in the Material Safety Data Sheets of the media to be
used in the system (if applicable).

______________________________________ Bronkhorst ® ______________________________________
________________________________________________________________________________________________
9.17.161 µ-FLOW & LIQUI-FLOW Instruction Manual L01, L13(I), L23(I), L13V12, L23V12
Page 8 of 50
1.3. Products descriptions
The µ-FLOW and LIQUI-FLOW instruments are measurement devices for thermal mass flow and control of liquids.
They are equipped with a digital electronic multi-bus pc-board and consist of a micro-controller with peripheral circuitry
for measuring, controlling and communication. The flow signal is measured, digitized and processed by means of the
internal software (firmware). The measured and processed values can be output through the analog interface or through
the digital communication line (RS232 or optional fieldbus interface).
For controllers the setting for the actuator is calculated by the firmware. The setpoint can be given through the analog
interface or through the digital communication line.
These digital instruments offer great flexibility thanks to the "multi-bus" concept, whereby the instruments can be
equipped with an optional fieldbus interface (CANopen, DeviceNet™, EtherCAT®, Ethernet/IP, FLOW-BUS, Modbus
(RTU/ASCII/TCP), POWERLINK, PROFIBUS DP, and PROFINET.
Numerous input/output options can be installed through the programmable 9-pin D-sub or 8DIN connector (see
Customized I/O). In addition to the various analog signal options and the standard RS232 communication, there are
such options as RS485 communication, digital frequency/pulse output, alarm output/reset, valve purge/close and analog
valve output.
The micro switches and LED’s on top of the instrument can also be used for manual operation of some options.
Control valves can either be integrally or separately mounted. The standard control valves on Bronkhorst® mass flow
controllers are suited for max. 100 bar pressure ratings. These valves are normally closed and available up to Kv-values
of 2.37 * 10-3. Normally open valves can also be supplied.
1.4. Product overview
Optional connector for fieldbus
Inlet connection
LED status indicator and push button
9-pin D-sub connector
Outlet connection
Optional connector for fieldbus
Inlet connection
LED status indicator and push button
9-pin D-sub connector
Outlet connection
Bronkhorst High-Tech B.V. cannot be held liable for any damage resulting from improper or unsafe
use, use for other than the intended purpose or use with other media and/or under other conditions
than specified on the purchase order.
See also section Sealing material compatibility.

______________________________________ Bronkhorst ® ______________________________________
________________________________________________________________________________________________
9.17.161 µ-FLOW & LIQUI-FLOW Instruction Manual L01, L13(I), L23(I), L13V12, L23V12
Page 9 of 50
Optional connector for fieldbus
Inlet connection
8DIN connector
LED status indicator and push button
Outlet connection
1.5. Calibration
The µ-FLOW and LIQUI-FLOW are factory calibrated. Periodical inspection, recalibration or verification of the accuracy
may be subject to individual requirements of the end user.
Bronkhorst certifies that the instrument meets the rated accuracy. Calibration has been performed using measurement
standards traceable to the Dutch Metrology Institute (VSL).
1.6. Maintenance
The µ-FLOW and LIQUI-FLOW needs no regular maintenance if operated properly, with clean media, compatible with
the wetted materials, avoiding pressure and thermal shocks and vibrations. Units may be purged with a clean, dry and
inert gas.
In case of severe contamination, cleaning the inside of the device may be required. After cleaning, recalibration of the
instrument is recommended.
1.7. Documentation
The µ-FLOW and LIQUI-FLOW come with all necessary documentation for basic operation and maintenance. Some parts
of this manual refer to other documents, most of which can be downloaded from the Bronkhorst website. Calibration
certificates, test certificates and material certificates are included in the scope of delivery or can be provided on request.
Type
Document name
Document no.;
IP40 enclosure
Document no.;
IP65 enclosure
Brochure
µ-FLOW and LIQUI-FLOW brochure
9.60.021 9.60.021
Manuals
Instruction manual µ-FLOW and LIQUI-FLOW (this document)
9.17.161 9.17.161
Quick Start Guide µ-FLOW and LIQUI-FLOW
n/a n/a
Hook-up diagram Analog/RS232
9.16.119 9.16.126
Depending on the ordering details, fittings and/or connectors on your instrument might differ from the
images above.
Inexpertly servicing instruments can lead to serious personal injury and/or damage to the instrument or
the system it is used in. Servicing must therefore be performed by trained and qualified personnel.
Contact your Bronkhorst representative for information about cleaning and calibration. Bronkhorst has
a trained staff available.
The documentation listed in the following table is available on the µ-FLOW and LIQUI-FLOW product
pages under www.bronkhorst.com/products

______________________________________ Bronkhorst ® ______________________________________
________________________________________________________________________________________________
9.17.161 µ-FLOW & LIQUI-FLOW Instruction Manual L01, L13(I), L23(I), L13V12, L23V12
Page 10 of 50
Technical
documentation
Hook-up diagram CANopen
9.16.217 9.16.216
Hook-up diagram DeviceNet™
9.16.122 9.16.129
Hook-up diagram EtherCAT®
9.16.124 9.16.253
Hook-up diagram EtherNet/IP
9.16.215 9.16.253
Hook-up diagram FLOW-BUS
9.16.120 9.16.127
Hook-up diagram Modbus ASCII / RTU
9.16.123 9.16.130
Hook-up diagram Modbus TCP
9.16.234 9.16.253
Hook-up diagram POWERLINK
9.16.236 9.16.253
Hook-up diagram PROFIBUS DP
9.16.121 9.16.128
Hook-up diagram PROFINET
9.16.147 9.16.253
Hook-up diagram custom bus & I/O configurations
9.16.118 9.16.125
Dimensional drawings model specific
Model specific Model specific
Type
Document name
Document no.
General documentation
EU Declaration of Conformaty
9.06.021
Communication interfaces
manuals
Manual CANopen interface
9.17.131
Manual DeviceNet™ interface
9.17.026
Manual EtherCAT® interface
9.17.063
Manual EtherNet/IP interface
9.17.132
Manual FLOW-BUS interface
9.17.024
Manual Modbus interface ASCII / RTU / TCP
9.17.035
Manual POWERLINK interface
9.17.142
Manual PROFIBUS DP interface
9.17.025
Manual PROFINET interface
9.17.095
Manual RS232 interface
9.17.027
The documentation listed in the following table is available on the µ-FLOW and LIQUI-FLOW product
pages under www.bronkhorst.com/products

______________________________________ Bronkhorst ® ______________________________________
________________________________________________________________________________________________
9.17.161 µ-FLOW & LIQUI-FLOW Instruction Manual L01, L13(I), L23(I), L13V12, L23V12
Page 11 of 50
2. Product specifications
Before installing the µ-FLOW and LIQUI-FLOW, check that the functional and technical properties of the product match
your requirements. If you have a question about the product or if you find the product does not meet the specifications
as ordered, do not hesitate to contact your Bronkhorst representative. See section Service for contact information.
The serial number label shows some essential technical specifications of the product as ordered (note that the image
does not necessarily reflect the actual specifications of your instrument):
•Serial number
•Type number
•Flow rate
•Medium
•Pressure
•Operating temperature
•Optional: valve type (N.C. - Normally Closed / N.O. - Normally Open)
The model key on contains more detailed information about the technical properties of the product as ordered.
Where applicable, follow the directions on any additional labels in order to ensure a safe working environment and to
comply with the regulations applicable to the product and its operating environment.
2.1. Pressure rating
2.2. Model key
The model key on the serial number label contains information about the technical properties of the instrument as ordered.
The specific properties can be retrieved with the diagrams below.
Avoid condensation on the sensor tube. Liquids entering the instrument with a lower temperature than
the dew point, may harm the instrument's functionality.
Bronkhorst®instruments are pressure tested to at least 1.5 times the specified operating
pressure and outboard leak tested to at least 2 * 10-9 mbar l/s Helium.
•The test pressure is specified on the device with a red label; if this label is missing or if the test
pressure is insufficient, the device must not be used and should be returned to the factory.
•Before installation, make sure that the pressure rating is within the limits of the normal process
conditions and that the tested pressure is in accordance with the safety factor of your application.
•Disassembling the device and/or replacing parts will invalidate the test pressure and leak test
specification.

______________________________________ Bronkhorst ® ______________________________________
________________________________________________________________________________________________
9.17.161 µ-FLOW & LIQUI-FLOW Instruction Manual L01, L13(I), L23(I), L13V12, L23V12
Page 12 of 50
NNA A A A N A
Code
D
Inlet Outlet
0 0
1 1
A
Code Controller mode
A
D
Controller enabled, analog setpoint
Controller enabled, digital setpoint
-- - -
N
2 2
Supply voltage
+ 15...24 Vdc
Adapters
None
1/8" OD compression type
1/4" OD compression type
LNNVNN
3 3 6 mm OD compression type
8 8 1/4" Face seal male
9 9 Other
A
Code Integrated comm. mode (pin 1/6)
A
B
RS232 – ProPar
RS485 – FLOW-BUS
CRS485 – Modbus RTU
DRS485 – Modbus ASCII
AAA
-
Range Par
1 V
1 V
3 A
Configurable input/output (pin 5)
0...10 Vdc output, controller
4...20 mA output, controller
Digital output, min/max alarm
0 I Digital output, high/low switch via remote parameter
9 B Digital pulse output, batch counter
8 C Digital input, controller mode valve purge
2 R Digital input, reset alarm
Type
A
B
C
C
F
I
I
* Default: Modbus RTU, optional Modbus ASCII
Supported options, see also pin 5 options table
1 R Digital input, reset counterI
5 S Digital output, enabled by setpoint (for shut-off) C
4 A Digital output, counter limit reachedC
Code Configuration
V12 Mass Flow Controller (MFC) NC
-Mass Flow Meter (MFM)
3 C Digital input, controller mode valve closeI
1 P 4...20 mA input, external pressure sensorH
0 0 0 Disabled, 0 Vdc (default)
0Controller disabled (meter only)
2 V 3.8...20.8 mA output, (TEIP11/Badger) controllerB
Code Sensor Code
20D 5...392 mg/h L01
50S 15...713 mg/h L01
60S 26...995 mg/h L01
A A 3 mm OD compression type
B B 1/8" Face seal male
C C 1/16" OD compression type
Code Analog output
A
B
0...5 Vdc
0...10 Vdc
F0...20 mA
dc sourcing
G4...20 mA
dc sourcing
Analog setpoint
0...5 Vdc
0...10 Vdc
0...20 mA dc sinking
4...20 mA dc sinking
V21 Mass Flow Controller (MFC) NO
MMetal (L01)
Code Sealing material
KKalrez/FFKM 6375
Code Field bus
ANone, I/O
BNone, I/O
Valve type
Normally Closed
Normally Opened
IEtherNet/IP I/O
KCANopen I/O
Normally Closed
Normally Closed
LCANopen I/O
MModbus I/O*
Normally Opened
Normally Closed
NModbus I/O* Normally Opened
DDeviceNet I/O Normally Closed
EDeviceNet I/O Normally Opened
CPowerlink I/O Normally Closed
JEtherNet/IP I/O Normally Opened
OPowerlink I/O
PPROFIBUS I/O
Normally Opened
Normally Closed
SFLOW-BUS I/O
UEtherCAT I/O
Normally Opened
Normally Opened
VPROFINET I/O
WPROFINET I/O
Normally Closed
Normally Opened
XModbus/TCP I/O Normally Closed
QPROFIBUS I/O Normally Opened
RFLOW-BUS I/O Normally Closed
YModbus-TCP I/O Normally Opened
TEtherCAT I/O Normally Closed
L01 µ-FLOW meter/controller, ≤2g/h
L13 LIQUI-FLOW meter/controller, ≤100g/h
L23 LIQUI-FLOW meter/controller, ≤1000g/h
Code Instrument type
70S 0.35...1.148 g/h L01
80S 0.56...2 g/h L01
10S 5...50 g/h Lx3
30S 50...500 g/h Lx3
70S 500...1000 g/h Lx3
ZOther
-

______________________________________ Bronkhorst ® ______________________________________
________________________________________________________________________________________________
9.17.161 µ-FLOW & LIQUI-FLOW Instruction Manual L01, L13(I), L23(I), L13V12, L23V12
Page 13 of 50
2.3. Sealing material compatibility
µ-FLOW and LIQUI-FLOW instruments are fitted from factory with internal seals compatible with the liquid type(s) as
specified at ordering time. Before using other media, always check their compatibility with the applied sealing materials.
Check the model key on the serial number label to see which sealing materials have been incorporated in your specific
instrument. When in doubt, do not hesitate to contact your Bronkhorst representative for more information.
2.4. Customised I/O options
Code
Decription
000
Disabled, M8/A2 is pulled down to 0Vdc (default selection)
A1V
0…10Vdc sourcing output, controller
Analog signal for pump or external valve steering (control signal only)
When the controller output is used for pump or external valve steering (mass flow meters only), make
sure to set parameter Valve maximum to 0.3 [A]. For mass flow controllers, the controller output is
limited to a value below 10Vdc, due to the maximum valve current restriction.
B1V
4…20mAsourcing output, controller
Analog signal for pump or external valve steering (control signal only).
When the controller output is used for pump or external valve steering (mass flow meters only), make
sure to set parameter Valve maximum to 0.3 [A]. For mass flow controllers, the controller output is
limited to a value below 20mA, due to the maximum valve current restriction.
B2V
3.8…20.8mA sourcing output, controller
Analog signal for Badger Meter valve with TEIP11 signal converter (control signal only).
C3A
Digital output, min/max alarm
During a min/max alarm, M8/A2 is pulled down to 0Vdc.
C4A
Digital output, counter alarm
During a counter alarm, M8/A2 is pulled down to 0Vdc.
C5S
Digital output, enabled by setpoint (for shut-off control)
M8/A2 is pulled down to 0Vdc at a controller setpoint, e.g. for shut-off valve activation.
For factory selected analog control:
If parameter Control mode is set for analog control by factory, the minimum setpoint at which the
device (shut-off valve) connected to M8/A2 is activated is 1.9%. This prevents possible noise on the
analog input activating the device accidentally.
For factory selected digital control:
If parameter Control mode is set for digital control by factory, the setpoint threshold for activating the
device connected to M8/A2 is any value > 0.
Note: If the instrument is forced into Valve Safe State, the digital output is not affected, so a (n/c)
shutoff valve connected to M8/A2 will not close when the (n/c) controller is in Valve Safe State’
Make sure to use 24Vdc power supply corresponding to the shut-off valve specifications.
C0I
Digital output, high/low switch via remote parameter (e.g. for shut-off valve control)
M8/A2 is pulled down to 0Vdc when writing value 1 to parameter IO switch status, this is undone by
writing value 0.
Adevice connected to M8/A2 (e.g. a shut-off valve) can be activated/de-activated by writing parameter
IO switch status.
Note: If the instrument is forced into Valve Safe State, the digital output is also affected, so a (n/c)
shutoff valve connected to M8/A2 will be closed when the (n/c) controller is in ‘Valve Safe State’.
Make sure to use 24Vdc power supply corresponding to the shut-off valve specifications.
D9E
Digital frequency output, measure
Measurement value is translated to a frequency within given frequency range.
•Always make sure that the used process gases or mixtures thereof are compatible with the sealing
materials the instrument is equipped with.
•Do not exceed the specified maximum operating pressure and temperature. Using the instrument
outside the specified operating limits might lead to serious damage and dangerous situations.

______________________________________ Bronkhorst ® ______________________________________
________________________________________________________________________________________________
9.17.161 µ-FLOW & LIQUI-FLOW Instruction Manual L01, L13(I), L23(I), L13V12, L23V12
Page 14 of 50
The default frequency range to represent 0…100% flow is 0…10000 Hz. Any other frequency range
must be specified on order.
F9B
Digital pulse output, batch counter
M8/A2 is pulled down to 0Vdc when a given batch size is reached (during a given pulse length).
By default, a pulse is given at each 1x the Counter unit batch value, with a pulse length of 1 second.
For instance, when Counter unit is set to 'ln', a pulse is given each time 1 ln has passed through the
instrument. An alternative pulse length must be specified on order.
Provide a pull-up resistor of 5…10kOhm to create 15…24Vdc at M8/A2 (according to the applicable
hook-up diagram).
I3C
Digital input, controller mode valve close
Valve closes when M8/A2 is connected to 0Vdc.
This option switches between the default Control mode and mode ‘Valve Close’ (value 3). When the
default Control mode is digital, the default value is 0 (bus/RS-232), when the default Control mode is
analog, the default value is 1 (Analog input).
I8C
Digital input, controller mode valve purge
Valve is fully opened when M8/A2 is connected to 0Vdc.
This option switches between the default Control mode and mode ‘Valve Fully Open’ (value 8). When
the default Control mode is digital, the default value is 0 (bus/RS-232), when the default Control mode
is analog, the default value is 1 (Analog input).
I1R
Digital input, reset counter
The counter resets when M8/A2 is connected to 0Vdc.
I2R
Digital input, reset alarm
The alarm resets when M8/A2 is connected to 0Vdc.

______________________________________ Bronkhorst ® ______________________________________
________________________________________________________________________________________________
9.17.161 µ-FLOW & LIQUI-FLOW Instruction Manual L01, L13(I), L23(I), L13V12, L23V12
Page 15 of 50
3. Installation
3.1. Mounting
For optimal performance, install the µ-FLOW and LIQUI-FLOW in a position free of vibration and away from heat
sources. The bottom of the instrument body is fitted with mounting holes; use these mounting holes to fixate the
instrument to a firm, rigid base or heavy, vibration free mass, such as a wall, a heavy rig or another stable construction.
Contact your local Bronkhorst representative for more information.
3.1.1. Orientation
Preferably, mount µ-FLOW and LIQUI-FLOW in an upright position.
3.1.2. Location in the fluid system
In liquid applications, the presence of gas bubbles in the liquid can cause measurement errors. If there is a risk of
expansion of dissolved gas in the metered liquid, the instrument should be mounted in a pipe segment where gas
bubbles cannot accumulate. The image below shows the preferable mounting locations.
•The best location is a horizontal pipe segment or a segment where the fluid direction is upward
•Gas might accumulate in a horizontal segment if it is followed by a downward segment. Do NOT
mount the instrument in a location like this
•Mounting in a downward pipe segment with an open end is strongly dissuaded, especially if the
pipe diameter is 1/2" or more. Gravity might cause the segment to drain; depending on the system
dimensions and the viscosity of the metered fluid, this effect might be stronger or weaker
•If the instrument is part of a closed fluid system, mounting the instrument in a downward pipe
segment is not preferable, but may be considered if other mounting locations are more
problematic.
3.1.3. Piping requirements
•Always use the mounting holes to fixate the instrument. Consult the dimensional drawing for the
exact locations and size of the mounting holes.
•Also make sure that the instrument is not suspended by the piping and take adequate measures to
isolate the instrument from vibrations in the piping.
•To minimize the risk of gas entrapment by cavitation, the preferred location to install a control
valve is downstream from the instrument, for a pump the preferred location is upstream.
•Avoid installation in close proximity of mechanical vibration and/or heat sources.
•Use the equipment in an environment with a stable ambient pressure and temperature.
•For reliable performance, make sure the fluid stream is uncontaminated. If necessary, use an inlet
filter to ensure a moisture, oil and particle free stream. Select a filter with a surface area and pore
size that minimize the pressure drop.
•If back flow could occur, the use of a check valve is also recommended.

______________________________________ Bronkhorst ® ______________________________________
________________________________________________________________________________________________
9.17.161 µ-FLOW & LIQUI-FLOW Instruction Manual L01, L13(I), L23(I), L13V12, L23V12
Page 16 of 50
3.1.4. Fluid connections
•Install the µ-FLOW and LIQUI-FLOW meter/controller in the process line, in accordance with the direction of the
FLOW arrow (see picture below) on the base of the instrument.
•For leak tight installation, follow the guidelines of the supplier of the fittings.
Bronkhorst® µ-FLOW and LIQUI-FLOW meters/controllers can be fitted with different fitting types (e.g. compression) or
special fitting types on request.
3.1.5. Mechanical isolation
3.2. Electrical connection
•Electrical connections must be made according to the applicable hook-up diagrams, using suitable cables with respect
to required supply current, voltage loss, cable and gland diameters and operating conditions.
•When using self-assembled cables, follow the guidelines provided by the connectors' manufacturer.
•For use in fieldbus systems, follow the instructions of the cable supplier for the specific fieldbus system.
•Make sure that the power supply is suitable for the power ratings as indicated on the serial number label (see model
key), and that double or reinforced insulation is used for the power supply.
•If a surge protection device is used, make sure its specifications match the power consumption of the application.
•Before powering up, make sure all required cabling is properly connected.
•Before each use, inspect cabling and connectors for damage.
µ-FLOW and LIQUI-FLOW instruments are powered with +15…+24 Vdc or +24 Vdc, depending on configuration or the
fieldbus system (if applicable).
•Check the fluid system for leaks before applying full operating pressure, especially when using
hazardous media (e.g. toxic or flammable).
•After using the µ-FLOW and LIQUI-FLOW for the first time with low temperature media, re-tighten
the fluid connectors in order to prevent leakage.
•Mechanical vibration may travel through piping or a mounting frame.
•Isolate instruments mechanically by mounting them on individual, rigid, stiff bases. Preferably,
mount multiple instruments parallel to each other, and use flexible piping if required.
To prevent damage as a result of reversed polarity, the use of a 2A fuse in the direct +Us line is
recommended.
Always isolate the electrical power before connecting or disconnecting equipment.
The device described in this document contains electronic components that are susceptible to
electrostatic discharge. In order to prevent damage, proper handling procedures must be followed
during installation, (dis)connecting and removing the electronics.
The device carries the CE-mark and is compliant with the concerning EMC requirements. However,
EMC requirements can only be met using appropriate cables and connector/gland assemblies.
Bronkhorst recommends the use of their standard cables. These cables have the right connectors and
loose ends (if any) are marked to help prevent wrong connection. When using other cables, cable wire
diameters must be sufficient to carry the supply current, and voltage loss must be kept as low as possible.
When in doubt, contact your Bronkhorst representative.

______________________________________ Bronkhorst ® ______________________________________
________________________________________________________________________________________________
9.17.161 µ-FLOW & LIQUI-FLOW Instruction Manual L01, L13(I), L23(I), L13V12, L23V12
Page 17 of 50
3.3. Fieldbus connection
If the instrument is provided with a dedicated fieldbus interface, it can be operated digitally in a fieldbus system, using
RS485 communication. In FLOW-BUS, Modbus, CANopen and DeviceNet™ systems, the fieldbus connector can also
be used to power the instrument. In other fieldbus systems, the instrument is always powered through the 9-pin D-sub
connector on the side or 8DIN power connector on top of the instrument.
The operation via analog interface, RS232 interface and an optional fieldbus can be performed at the same time. A
special parameter called “control mode” indicates which connection is controlling the instrument: analog or digital (via
fieldbus or RS232). Even when using more interfaces at the same time, the reading can be done simultaneously. When
changing a parameter value, the last value send by an interface will become valid.
3.3.1. FLOW-BUS
FLOW-BUS is a Bronkhorst® designed fieldbus, based on RS485 technology, for digital communication between
devices, offering the possibility of host-control by a Windows computer.
Characteristics:
•Baud rate 187,500 (default) or 400,000 Baud
•+15…24 Vdc supply voltage
•Easy installation and communication with other Bronkhorst®devices
•Automatic node search and bus optimisation (gap fixing)
•RS232 communication (ProPar) with Windows computer (local host)
•Connection of up to 120 instruments on a single bus
•Maximum bus cable length: 600 m
3.3.2. Modbus
Modbus is a 3-wire, RS485-based fieldbus communication system for parameter value exchange. In this system each
instrument/device is equipped with a micro-controller for its own dedicated task. The instrument behaves as a slave,
which means all communication (instructions and readout) is initiated by a master device on the Modbus system.
Characteristics:
•Baud rate selectable between 9,600 and 256,000 Baud (default: 19,200 Baud)
•+15…24 Vdc supply voltage
•Connection of up to 247 instruments on a single bus
•Supports RTU and ASCII protocols
When connecting the product to other devices, be sure that the integrity of the shielding is not affected;
always use shielded cabling for signals and communication and do not use unshielded wire
terminals.
Never power the instrument simultaneously from two different power sources (e.g. fieldbus and
Plug-in Power Supply). Doing so will damage the printed circuit board irreparably.
Always check the total power consumption of your instruments before connecting them to a fieldbus
system. Do not exceed the maximum power of the power supply unit.
If you need assistance with setting up a bus configuration, contact your Bronkhorst representative for
information.
Consult Instruction manual FLOW-BUS interface (document no. 9.17.024) for more information about
setting up a FLOW-BUS network.

______________________________________ Bronkhorst ® ______________________________________
________________________________________________________________________________________________
9.17.161 µ-FLOW & LIQUI-FLOW Instruction Manual L01, L13(I), L23(I), L13V12, L23V12
Page 18 of 50
3.3.3. Other fieldbuses
For other fieldbuses consult the concerning fieldbus manual.
Consult Instruction manual Modbus interface (document no. 9.17.035) for more information about
setting up a Modbus network.

______________________________________ Bronkhorst ® ______________________________________
________________________________________________________________________________________________
9.17.161 µ-FLOW & LIQUI-FLOW Instruction Manual L01, L13(I), L23(I), L13V12, L23V12
Page 19 of 50
4. Operation
After correct installation and taking all necessary safety precautions, the µ-FLOW and LIQUI-FLOW can be used to
measure and/or control flow.
4.1. Powering up
When powering up, the instrument needs a couple of seconds to start up the electronics and perform a self-test. After
successful initialization, the green LED will glow continuously to indicate that the instrument is ready to use.
4.2. First use
4.3. Preventing slug flow
4.4. Rapid gas decompression / explosive decompression
To maintain control of the fluid system and ensure a safe situation, it is recommended to turn on power
before applying fluid pressure and to switch off power only after the fluid system is depressurized
When applying pressure, avoid pressure shocks and bring the fluid system gradually up to the level of
the specified operating conditions; open the fluid supply gently.
For best performance, allow the device to warm up and stabilize for at least 30 minutes before starting
measurement and/or control. This may be done with or without media flow.
•Despite the fact that everything necessary has been done to ensure the cleanliness of the product
upon delivery, the presence of some remaining contaminants cannot be ruled out completely.
•In order to prevent undesired reactions, purging the instrument for a minimum of 30 minutes with a
dry, inert gas (like Nitrogen or Argon) is recommended before first use. In systems for use with
corrosive or reactive media, this is even absolutely necessary.
•During the manufacturing process, the instrument has been tested with water. Purging prior to first
use is also recommended to remove any remaining water droplets.
The very first time the instrument is used, adjusting the zero point is recommended. See Adjusting zero
point for background information and instructions.
Reliable measurement results can only be obtained if the fluid flows through the instrument in a single
state, for µ-FLOW and LIQUI-FLOW should it be liquid. The following measures can help prevent so
called 'slug flow' (two-phase flow):
Before starting measurement and control: remove (dissolved) gas from the system, by flushing the
instrument and all fluid lines with the process fluid at a high flow rate
During measurement and control:
•avoid external heating or cooling (can cause gas bubbles in liquid).
•avoid extreme pressure fluctuations (can cause cavitation in liquid).
For instruments used above 10 bar (g):
Bronkhorst recommends a maximum decompression rate of 70 bar/min, according to NACE TM0297.
Exceeding this rate can have negative influence on the lifetime of the sealing materials.

______________________________________ Bronkhorst ® ______________________________________
________________________________________________________________________________________________
9.17.161 µ-FLOW & LIQUI-FLOW Instruction Manual L01, L13(I), L23(I), L13V12, L23V12
Page 20 of 50
4.5. Mass flow measurement and control
When powering up, the instrument needs a couple of seconds to
start up the electronics. As soon as the start-up sequence has
finished (green LED glows continuously), the instrument is ready to
measure mass flows, however, optimal accuracy is only reached
after warming up (see Powering up and powering down).
After powering up, the control valve closes (normally open) or stays
closed (normally closed). The valve stays closed until the instrument
receives a setpoint from the active setpoint source. The internal PID
controller then immediately opens the control valve, until the
measured flow rate matches the setpoint. It maintains the resulting
flow rate until another setpoint is given.
4.6. After use
4.7. Powering down
4.8. Valve safe state
The µ-FLOW and LIQUI-FLOW can operate an external control valve, using the analog actuator output signal.
When a controlling instrument is not powered or cannot communicate with the fieldbus network (if applicable), all
electrical valves operated by the instrument (whether integrated or external) automatically return to their default state.
The default state is closed for 'normally closed' valves (n/c) and fully open for 'normally open' valves (n/o). Taking into
account the typical process conditions under which the instrument is used (such as the processed media and ambient
conditions; see also Intended use), the default state is generally considered safe.
Check the serial number label or the technical specifications to see which valve type is used on your instrument (if
applicable).
4.9. Temperature considerations
Although the µ-FLOW and LIQUI-FLOW have excellent temperature stability, the best accuracy is achieved when
temperature gradients within and across the instrument are prevented. Observe the following attention points:
•Keep the media temperature as close as possible to the ambient temperature, and above the dew point of the
ambient air.
•Do not allow the media temperature to drop more than 10 °C below the ambient temperature or take measures to
prevent condensation.
•Always keep the media temperature above the freezing point.
•To prevent simultaneous heating and cooling of different parts of the instrument, make sure the ambient
temperature is as stable and evenly distributed across the environment as possible.
•Prevent temperature shocks; heating or cooling should amount to no more than 1 °C per second.
•Depending on the properties of the process medium and the (expected) time until the next use, it
is advisable to flush the fluid system with a suitable (cleaning) fluid after use.
•If the equipment has been used to process corrosive, reactive or hazardous media (e.g. toxic or
flammable), cleaning the fluid system is even absolutely necessary before it is exposed to air.
•If the instrument is not used for an extended period, the fluid system should be dry after use and
after cleaning. If not, it should be purged with a dry, inert gas for a recommended minimum period
of 30 minutes.
•Prior to powering down the µ-FLOW and LIQUI-FLOW, the fluid system should be depressurized.
•When depressurizing, prevent sudden pressure changes, by shutting off the fluid supply gradually.