Meatest M921 User manual

M921 Electromagnetic flowmeter
User’s manual

Electromagnetic Flowmeter M921 MEATEST
2 Operation manual
Content
1Basic information..............................................................................................................................5
1.1 Basic features ..................................................................................................................................5
1.2 Warranty .........................................................................................................................................5
2Mechanical installation.....................................................................................................................6
2.1 Sensor location ................................................................................................................................6
2.2 Sensor grounding.............................................................................................................................9
3Preparing for start up......................................................................................................................10
3.1 Safety precautions.........................................................................................................................10
3.1.1 Safety symbols used on the equipment ................................................................................10
3.2 Inspecting contents of the package...............................................................................................10
3.3 Electronic unit description .............................................................................................................11
3.3.1 Front panel ............................................................................................................................11
3.3.2 Under the lid of the flowmeter case .....................................................................................12
3.4 Electrical connection......................................................................................................................13
3.4.1 Power supply .........................................................................................................................13
3.4.2 Fuse replacement ..................................................................................................................15
3.4.3 Electric connection between converter and sensor –Remote version.................................16
4Flowmeter configuration ................................................................................................................17
4.1 Main menu ....................................................................................................................................17
4.1.1 Overview ...............................................................................................................................17
4.1.2 Datalogger .............................................................................................................................17
4.1.3 Status.....................................................................................................................................17
4.1.4 Flow .......................................................................................................................................17
4.1.5 Volume ..................................................................................................................................17
4.2 Setup menu....................................................................................................................................18
4.2.1 General ..................................................................................................................................18
4.2.2 Measurements ......................................................................................................................19
4.2.3 Input/output interface ..........................................................................................................20
4.2.4 Calibration .............................................................................................................................21
4.3 Nominal values (standard factory setting) ....................................................................................22
4.3.1 General ..................................................................................................................................22
4.3.2 Measurements ......................................................................................................................22
4.3.3 Inputs / outputs.....................................................................................................................23
5Inputs and outputs configuration....................................................................................................24
5.1 General purpose inputs and outputs .............................................................................................24
5.1.1 Current output.......................................................................................................................24
5.1.2 Frequency output ..................................................................................................................25
5.1.3 Pulse output ..........................................................................................................................26
5.1.4 Status (relay) output..............................................................................................................28
5.1.5 PLC digital input.....................................................................................................................29
5.1.6 Limits .....................................................................................................................................29
5.1.7 Dosing....................................................................................................................................30
5.1.8 RS485 interface .....................................................................................................................31
5.1.9 USB/RSR232...........................................................................................................................31

MEATEST Electromagnetic flowmeter M921
Operation manual Version 10 3
5.2 Command syntax ...........................................................................................................................32
5.2.1 Syntax description .................................................................................................................33
5.2.2 Command list.........................................................................................................................33
Datalogger filling (percentage)...............................................................................................................48
DPC?.....................................................................................................................................................48
6Maintenance ...................................................................................................................................56
6.1 Recommendations for correct operation.......................................................................................56
6.2 Periodical maintenance .................................................................................................................56
6.3 What to do in case of failure .........................................................................................................56
6.4 Error messages ..............................................................................................................................57
7Application information ..................................................................................................................58
7.1 Specifications .................................................................................................................................58
7.2 Weight and dimensions .................................................................................................................59
7.2.1 Electronic unit........................................................................................................................59
7.2.2 Electronic unit –remote version ...........................................................................................60
7.2.3 Sensor ....................................................................................................................................62
7.3 Used materials...............................................................................................................................63
7.4 Used pluggable terminal block connectors....................................................................................63
7.5 Flowrate versus diameter ..............................................................................................................64
7.6 Type plate ......................................................................................................................................65
7.7 Terminology...................................................................................................................................67
7.8 Measuring principle .......................................................................................................................68
8Ordering information ......................................................................................................................69
8.1 Options ..........................................................................................................................................69
8.2 Extra ordered options ....................................................................................................................69
8.3 Example of order ...........................................................................................................................69

Electromagnetic Flowmeter M921 MEATEST
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Tables
Table 1: Power supply ranges and fuse ratings.............................................................................................15
Table 2 : Remote version connections ..........................................................................................................16
Table 3 : User access .....................................................................................................................................18
Table 4 : General settings..............................................................................................................................18
Table 5 : Settings for measurement ..............................................................................................................20
Table 6 : Input/output interface setup..........................................................................................................21
Table 7 : User calibration ..............................................................................................................................21
Table 8 : Nominal values - general ................................................................................................................22
Table 9 : Nominal values –measurements ...................................................................................................23
Table 10 : Nominal values - inputs/outputs ..................................................................................................23
Table 11 : Error mask ....................................................................................................................................29
Table 12 : USB/RS232 properties ..................................................................................................................32
Table 13 : RS232 error codes.........................................................................................................................32
Table 14 : State output error mask ...............................................................................................................41
Table 15 : Errors ............................................................................................................................................57
Table 16 : Dimensions and weights –DIN flanges.........................................................................................62
Table 17 : Used materials..............................................................................................................................63
Table 18 : Connector types............................................................................................................................63
Table 19 : Applicable flowrates for various diameters..................................................................................64
Table 20 : Options .........................................................................................................................................69

MEATEST Electromagnetic flowmeter M921
Operation manual 5
1Basic information
1.1 Basic features
The inductive flow meter M921 is designed to measure, indicate and record the instantaneous and total flow
of the conductive media flowing through the sensor. The flow meter M921 records both forward and reverse
flows. As there are no moving parts in the flow profile the M921 can be used to measure extremely dirty
liquids containing solids. The only limitation is that the flowmeter can be used solely with conductive liquids.
Range of applications. The inductive flow meter M921 is for use in the Chemical Industry, Paper Industry,
Water and Wastewater Treatment Industry and most other process industries.
Features. The inductive flowmeter M921 is a highly accurate and stable device. The construction of the
M921 flowmeter uses components with long-term, time and temperature stability. Configuration data is
backed up and can be recovered after a power failure. The back-up structure enables data recovery even if a
partial loss of data occurs as a result of (e.g. high level electrostatic discharge or a noisy power supply).
Internal CPU provides all functions usually built in electronic flow meters, incl. low flow rate correction,
frequency response setting, bandwidth of sensitivity setting at low flow rates, etc.
Outputs. Flowmeter M921 is equipped with 6 standard isolated outputs: 4 to 20mA either active or passive,
frequency output, impulse output, status output (with relay), RS485 and USB/RS232 output. User can
configure these outputs.
Inputs. Flowmeter M921 has one programmable digital input (PLC).
Power supply. Basic power supply version is 85 to 264 V AC. 12, 24 and 48 DC power supply versions are
also available as an option.
1.2 Warranty
Within the manufacturers general supply conditions, all material and manufacturing faults are covered by
warranty. Upon warranty claim, Meatest will test the item and decide whether to repair it or replace with a
new one. Place of the warranty obligation is Czech Republic. Further claims on compensation, especially for
loss of production or resultant of damages, are strictly excluded.
Any defects caused by improper use are absolutely not included in the warranty. Excluded from warranty are
also expendable items (as i.e. accumulators, batteries, pushbuttons after attained life time, ribbons, etc.)
In case of a warranty claim the user is asked to give detailed description of the defect and also of the
application for which user use the product. This information is important in order to avoid time and cost
extensive tests and for the eventual achievement of warranty claims from our suppliers and sub-suppliers.
For the item or instrument, returned after the expired warranty time, repair or replacement on warranty can
only be accepted, if manufacturer has been informed in time that a warranty case has occurred.
Warranty period for all types of electromagnetic flowmeter is 24 months.
The flowmeter should only be used
according to the instructions described in
this operating manual.

Electromagnetic Flowmeter M921 MEATEST
6 Operation manual
2Mechanical installation
2.1 Sensor location
Observe the following instructions to avoid measurement errors due to air bubbles or partially filled pipe.
Flowmeter should be installed in such way, that all electronic controls (such as display, keyboard,
input/output connectors) are easily accessible. Please observe and allocate enough room for opening
flowmeter hinged lid.
Horizontal (standard) mounting
The sensor tube must always remain full. The best way to achieve this is to locate the sensor in a low section
of pipe, see the following picture. It is recommended to install the sensor in a section of straight pipe with at
least 5 times the pipe diameter before sensor and 3 times after sensor.
5 DN
3 DN
5 DN
3 DN

MEATEST Electromagnetic flowmeter M921
Operation manual 7
Pipe reducers
If the pipe diameter is not the same as the diameter of sensor, then pipe reducers can be used. So as not to
lose accuracy of the measurement, the slope of reducers should not exceed 8.
Vertical mounting
When the sensor is mounted on a vertical section of pipe, the flow direction must be upwards. In the case of
a downward flow direction, air bubbles could collect in the sensor resulting in unstable and inaccurate
measurement.
Pumps
Never install the sensor on the suction side of a pump or on a section of pipe where a vacuum is possible.
8

Electromagnetic Flowmeter M921 MEATEST
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Valves
Suitable location of a shutoff valve is downstream of a sensor.
Removal during maintenance
If the application requires removal of the sensor for periodic maintenance, it is recommended to install a
bypass section as the following drawing.
Position of electrodes
The axis of measuring electrodes must be approximately horizontal (see picture).
YES NO

MEATEST Electromagnetic flowmeter M921
Operation manual 9
Vibration
To avoid mechanical damage protect both electronic unit and sensor against mechanical vibrations. When
strong vibrations are possible, both the input and output pipe must be mechanically fixed or the remote
version with a separate electronic unit should be used.
Overheating
To avoid overheating, the electronic unit should be protected against direct sunlight especially in areas with
a warm climate with ambient temperatures over 30 °C. If necessary a sunshade has to be mounted over the
electronic unit or a remote version with a separate electronic unit should be used.
2.2 Sensor grounding
Proper grounding is critical for correct flow meter operation. The sensor is equipped with screw connection
for a grounding wire. This screw has to be connected to both pipeline flanges. Use Copper wire to connect
between the flange and the grounding screw on the sensor.
If the pipeline is made of an electrically nonconductive material, or if the pipe is lined with a similar material,
special grounding rings must be installed between flanges.
Sensor grounding without grounding rings Sensor grounding with grounding rings
Caution!
Do not switch the flow meter on if it’s not properly grounded.
Follow instructions in chapter 3 :Preparing for start up for proper electrical installation
before switching flow meter on.

Electromagnetic Flowmeter M921 MEATEST
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3Preparing for start up
3.1 Safety precautions
The instrument has been designed according to EN 61010-1:2011. Safety is ensured by the design and by the
use of specific component types. Manufacturer is not liable for the damage caused by not following
instructions present in this manual or modification of the construction or replacement of parts with non-
original ones.
3.1.1 Safety symbols used on the equipment
Warning, reference to the documentation
Lucy286
3.2 Inspecting contents of the package
Basic package includes the following items:
Flanged sensor
Electronic Transmitter (integral or remote)
Spare fuse
Operating manual.
Calibration certificate
Software FlowAssistant
USB A-B cable
The flowmeter is delivered ready for use after connecting to the power supply. Please check that it has been
correctly installed according to chapter Mechanical before turning power on. Only a power supply with the
appropriate voltage and frequency must be used, see ordering information in chapter “Power supply”.
Caution!
Only a competent person may connect the flowmeter to the mains power supply.
To prevent accidents, connect main power only after all other wiring has been
completed.
Use only specified voltage and frequency for user flow meter version.
Take national applicable laws and rules into account.