PCE Instruments UMI 840 User manual

UMI 840 Durchflussmessgerät | Ultrasonic Flow Meter
Bedienungsanleitung
User Manual
Letzte Änderung / last change: 6 September 2017
V 1.3
DE
EN

English
Contents
1Safety notes 21
2Specifications 22
2.1 Technical specifications 22
2.2 Delivery contents 23
2.3 Optional accessories 23
3System description 24
3.1 Device 24
3.2 Function keys 26
4Getting started 26
4.1 Internal battery 26
4.2 Power on 26
4.3 Menu windows 27
5Operation 28
5.1 Principle of measurement 28
5.2 Configuration of parameters 29
5.3 Sensors 31
5.4 Data logger 36
6Calibration 36
7Maintenance 36
7.1 Troubleshooting 36
8Warranty 39
9Disposal 39

21
English
Thank you for purchasing an ultrasonic flow meter from Dostmann electronic.
1 Safety notes
Please read this manual carefully and completely before you use the device for the first time. The
device may only be used by qualified personnel and repaired by Dostmann electronic personnel.
Damage or injuries caused by non-observance of the manual are excluded from our liability and not
covered by our warranty.
The device must only be used within the approved temperature range:
Environmental humidity max. <80 % RH
Environmental temperature 0 ... +70 °C
Do not expose the device to extreme temperatures, direct sunlight, extreme humidity,
condensation or moisture.
Never use the instrument when your hands are wet.
Before taking a measurement, the device should be stabilised to the ambient temperature
(important when carrying the device from cold to warm rooms and vice versa).
Avoid strong shocks.
Do not use the meter around corrosive or explosive gases.
The case should only be opened by qualified Dostmann electronic personnel.
Repairs and maintenance work may only be carried out by qualified Dostmann electronic
personnel.
Never place the front side of the device on a workbench or work surface to avoid damage
to the operating elements.
You must not make any technical changes to the device.
Keep the flow meter clean and dry.
The appliance should only be cleaned with a damp cloth. Use only pH-neutral cleaner, no
abrasives or solvents.
Non-observance of the safety notes can cause damage to the device and injuries to the
user.
We do not assume liability for printing errors or any other mistakes in this manual.
We expressly point to our general guarantee terms which can be found in our general terms of
business.
If you have any questions please contact Dostmann electronic. The contact details can be found at
the end of this manual.

22
English
2 Specifications
2.1 Technical specifications
Hand-held device
Model
UMI 840
Measurement range
-32 ... +32 m/s
Resolution
0.0001 m/s
Accuracy
for NPS ≥50 mm: ±1.5 % of reading
for NPS < 50 mm: ±3.5 % of reading
Repeatability
±1.0 % of reading
Media
All liquids with an impurity of <5 % and a flow of >0.03m³/h
Flow units
Cubic metre [m³]
Litre [l]
Gallon (USA) [gal]
Imperial Gallon (UK) [igl]
Million USA Gallons [mgl]
Cubic foot [cf]
Barrel (USA) [bal]
Imperial Barrel (UK) [ib]
Oil Barrel [ob]
The time can be per day [/d], per hour [/h], per minute [/m] and per
second [/s]
Data logger
1800 measuring data
Interface
USB (for online measurement and to read out internal memory)
Protection class
IP 52
Power supply
3 x rechargeable AA NiMH batteries / 2100 mAh (operating hours
12 h when fully charged)
100 …240 V AC 50/60 H
Dimensions
214 x 104 x 40 mm
Weight
450 g

23
English
Sensors
Type of
sensor
S1
M1
Order no.
sensor
UMI-S1
UMI-M1
Order no.
hand-held
device +
sensor
6050-0840
6050-0841
Sensor cable
length
5m
5m
Nominal
diameter
DN 15 … DN 100
20 … 108 mm
DN 50 …DN 700
57 … 720 mm
Liquid
temperature
-30 … 160 °C
-30 … 160 °C
Dimensions
45 x 30 x 30 mm
60 x 45 x 45 mm
Weight
75 g
260 g
2.2 Delivery contents
1 x ultrasonic flow meter
2 x sensor (depending on model)
2 x 5 m connection cable
2 x releasable cable tie
1 x mains adaptor
1 x contact gel
1 x measuring tape
1 x carrying case
1 x user manual
1 x factory calibration certificate
2.3 Optional accessories
UMI-M1 Sensor type M1 (loose)

24
English
3 System description
3.1 Device
Top view
Front view
Bottom view
1 Sensor connection (up)
2 Sensor connection (down)
3 Display
4 LED charging lamp
5 Membrane keypad
6 Charging socket
7 USB interface

25
English
Cable 5 m (2 x)
1 Plug orange
2 Plug blue
Mains adaptor

26
English
3.2 Function keys
The keypad consists of 18 keys. The keys from 0 to 9 and the decimal point are used to enter
numbers
Key
Name
Function
Up / + key
Press to select different window or enter numbers
Down / - key
Back key
Press to go one step back or move cursor left
ENTER key
Press to confirm or make a selection
MENU key
Press to enter menu mode or press followed by
two digits to enter a certain menu window
ON / OFF key
Press to switch ON / OFF
Reset key
Press to reset device to factory default settings
4 Getting started
4.1 Internal battery
The device can be powered either by the internal rechargeable battery (more than 12 hours with
continuous operation) or via the mains adaptor.
During charging, the LED glows red. It will turn green as soon as the battery is fully charged.
When the battery is fully charged, the voltage is approx. 4.25 V. The voltage is shown in window
M07. The battery is nearly flat when the voltage falls below 3 V. The device also indicates the
remaining battery life which is determined internally via the voltage. The indication of the remaining
battery life is just a rough guide value.
4.2 Power on
The device can be switched on via the ON key and switched off using the OFF key. After switching
on, the device runs a self-diagnostic programme. The hardware and the internal software are tested.
If an error is detected, this will be shown in the display.

27
English
After the start-up, the device will show window M01. This is the most common window und shows
the positive totaliser, the volume flow, the flow velocity, the signal strength, the signal quality and the
operating status, based on the values last set for the pipe.
4.3 Menu windows
M00 … M09
Window for volume flow, velocity, date, time, totaliser, battery voltage,
remaining battery life, etc.
M10 … M29
Window for pipe parameters, etc.
M30 … M38
Window for unit selection and totaliser
M40 … M49
Window for response time, zero setting, calibration and PIN protection,
etc.
M50 … M53
Window for data logger
M60 … M78
Window for date / time setup, display of software version and serial
number, alarm, etc.
M82
Window for total operating time
M90 … M94
Diagnostic window for better accuracy
M97 … M99
Commands for saving pipe parameters, diagnostic information and display
indications
M+0 --- M+8
Window for additional functions, including a scientific calculator, overviews
of operating hours, ON / OFF times, …
The device has approx. 100 menu windows. These windows are numbered from M00, M01, M02,
M03…, through to M99.
There are two ways to select these windows:
(1) Directly, using the MENU key and the two digits
(2) Via the Up / Down keys; each keystroke changes to the next higher or previous window,
whereas the window M00 is at the top, which means that the Down key will lead you to the
next higher window.
The device has three different types of windows:
(1) Window to enter numbers, e. g. M11 to enter the pipe diameter
(2) Window to select options, e. g. M14 to select the pipe material
(3) Windows to view data, without being able to make a selection, e. g. M+1 to show the
complete operating time of the device
About (1): When you are in a window for data entry, you can enter the data and confirm with ENTER.
For example, if you are in window M11, you can directly enter
for the outer diameter of the pipe.
About (2): In a selection window, first press the ENTER key and then make a selection using the Up
and Down keys or the number keys if a number needs to be selected. Finally, confirm your selection
with the ENTER key.
Example M 14 (material selection):
Stainless steel, for instance, is assigned no. 1. To select a different material, press ENTER to be
able to make your selection using the Up and Down keys. Confirm your selection with ENTER. You
can also enter the numbers directly via the numeric keypad.

28
English
5 Operation
5.1 Principle of measurement
The ultrasonic flow meter has been developed to measure the flow velocity of liquids in pipes. The
non-contact transducers / sensors are placed on the pipes and are thus not subject to any wear and
tear.
The UMI 840 works with two signal transducers (sensors) which serve as ultrasonic transmitters and
also as ultrasonic receivers. The sensors are installed on the outer wall of the pipe at a defined
distance, one below the other.
The sensors can be installed in Z shape (Z method). In this case, the ultrasound will pass through
the pipe once. If the sensors are installed in W shape (W method), the ultrasound will pass through
the pipe four times. When using the Z method, the sensors are placed opposite to each other. The
sound passes through the pipe or liquid diagonally. The selection of the right method depends on the
characteristics of the liquid.
1 Downstream transducer
2 Flow direction
3 Upstream transducer
4 Spacing
You can find more detailed information on how to place the sensors and how to select the right
method of measurement in chapter 5.3.Sensors.

29
English
5.2 Configuration of parameters
Menu
Function
M00
View three totalisers (positive, negative, net), signal strength, signal quality
and operating status
M01
View positive totaliser, volume flow, velocity, signal strength, signal quality and
operating status
M02
View negative totaliser, volume flow, velocity, signal strength, signal quality
and operating status
M03
View net totaliser, volume flow, velocity, signal strength, signal quality and
operating status
M04
View date and time, volume flow, signal strength, signal quality and operating
status
M05
View date and time, velocity, signal strength, signal quality and operating
status
M06
Waveform of the received signal
M07
View battery voltage and remaining battery life
M08
View each operating status, signal strength and signal quality in detail
M09
Display today’s volume flow, velocity, signal strength, signal quality and
operating status
M10
Enter outer perimeter of pipe
M11
Enter outer diameter of pipe, value between 0 and 6,000 mm can be selected
M12
Enter wall thickness of pipe
M13
Enter inner diameter of pipe
M14
Select standard pipe material (if pipe material is included here, no pipe sound
velocity is needed):
0. Carbon Steel, 1. Stainless Steel, 2. Cast Iron, 3. Ductile Iron, 4. Copper,
5. PVC, 6. Aluminium, 7. Asbestos, 8. Fiber Glass 9. Other
M15
Enter pipe sound velocity; only necessary if material does not belong to
standard materials
M16
Select liner material; if the pipe used does not have a liner, select „0. No Liner“
1. Tar Epoxy, 2. Rubber, 3. Mortar, 4. Polypropylen, 5. Polystyrol,
6. Polystyrene, 7. Polyester, 8. Polyethylene, 9. Ebonite, 10. Teflon, 11. Other
M17
Enter liner sound velocity; only necessary if material is not listed under M16
M18
Enter material thickness of liner
M19
Enter absolute thickness of inner wall
M20
Select standard liquid:
0. Water, 1. Sea Water, 2. Kerosene, 3. Gasoline, 4. Fuel Oil, 5.Crude Oil,
6. Propane, 7. Butane, 8. Other, 9. Diesel Oil, 10. Castor Oil,
11. Peanut Oil, 12. Gasoline ROZ 90, 13. Gasoline ROZ 93, 14. Alcohol, 15.
Water (125 °C)
M21
Enter fluid sound velocity; only necessary if liquid does not belong to standard
liquids
M22
Enter viscosity of liquid (only necessary if liquid does not belong to standard
liquids)
M23
Select sensors out of 16 types:
1. Plug-in Type A
2. Clamp-on TM-1
3. User Type
4. Standard-B
5. Plug Type B45
6. Standard-L
7. Clamp-On TS-2
8. Standard-M1

30
English
9. Plug-in Type C
10. Standard-HS
11. Standard-HM
12. Standard-S1
13. π-Pipe
14. Standard-L1
15. Clamp-On TL-1
16. Standard-M
M24
Select sensor installation:
0. V method, 1. Z method, 2. N method, 3. W method
M25
View distance between sensors; should be stuck to as exactly as possible
M26
Save parameters to internal memory (18 memory locations)
M27
Read out saved parameters
M28
Select whether or not device should hold last good value when signal is
insufficient; standard setting is YES
M29
Low limit signal strength (default 35)
M30
Select unit system: metric or English
M31
Select flow rate unit:
Cubic Meters [m³]
Liters [l]
USA Gallons [gal]
Imperial Gallons [igl]
USA M Gallons [mgl]
Cubic Feet [cf]
USA Barrels [bal]
Imperial Barrels [ib]
Oil Barrels [ob]
Time can be per day, per hour, per minute or per second, which means 36
different unit combinations are possible
M32
Select operating unit of totaliser (options as in M31)
M33
Multiplier totaliser (default 1)
M34
Enable / disable net totaliser
M35
Enable / disable positive totaliser
M36
Enable / disable negative totaliser
M37
1. Reset totaliser
2. Reset device to factory default settings by pressing Reset key, followed by
Back key. Be careful with this function and note down your personal
settings before using it
M38
Start or stop totaliser by means of ENTER key
M39
Select the language (English or French)
M40
Set damping which can be a value between 0 and 999 seconds; if “0“ is
selected, damping is disabled
M41
Set low cutoff value
M42
Set zero point; make sure no liquid passes through the pipe
M43
Delete zero point, reset to default zero point
M44
Set flow value manually (offset value); this value should normally be “0“
M45
Set scale factor; this value is set to the delivered sensors by Dostmann
electronic before shipping and should only be changed after a calibration by
Dostmann electronic
M46
View network IDN
M47
Lock device; parameters cannot be changed anymore
M48
Not in use
M49
Comm tester
M50
Enable or disable data logging function
M51
Set start time, interval and go on (run) time of the logger

31
English
M52
Select memory
0. To RS232
1. To Buffer
2. Buffer => RS232
The RS232 signal is transmitted via the USB interface.
M53
View saved data in internal memory; navigate through data using Reset, Back,
Up and Down keys; indication is updated automatically if logger has been
activated
M60
View date and time (calendar for 99 years); press ENTER to make changes;
press Reset to go to the next digit
M61
View software version and serial number (ESN)
M62
Setup USB interface:
Baud rate from 75 to 115200 bps
Parity None, Odd or Even
M67
Select frequency range for output between 0 and 9999, default setting is 1 to
1001 Hz
M68
Set volume flow for lowest frequency
M69
Set volume flow for highest frequency
M70
Set display backlight; select how many seconds backlight will glow without
keystroke
M72
Reset working timer; press ENTER and confirm by selecting YES
M73
Set low value for alarm #1; there are two alarms; alarm output can be set via
M77 and M78
M74
Set high value for alarm #1
M75
Set low value for alarm #2
M76
Set high value for alarm #2
M77
Set up acoustic signal
M82
Date totaliser (by day, month or year)
M85
Activate or deactivate Auto Power Off function (device powers off after 4
minutes of inactivity to save energy)
M90
View signal strength, signal quality, time ratio in the upper right corner
M91
View ratio between measured and calculated total transit time; if all pipe
parameters have been entered correctly and the sensors have been installed
correctly, the ratio should be around 100 % ±3 %; if not so, check all
parameters and sensor installation
M92
View estimated fluid sound velocity; if there is an apparent difference to the
actual fluid sound velocity, check all parameters and the sensor installation
M93
View total transit time and delta time (transit time difference)
M94
View Reynolds number and pipe factor the device uses
M+0
Read out 64 recorded data (Switch-on / switch-off date and time, time at which
flow was measured)
M+1
View total operating time of device
M+2
View date and time of last switch-off
M+3
View last volume flow before switch-off
M+4
View how often device was switched on
M+5
Scientific calculator (complicated to use)
M+6
Set flow velocity
M+7
Select protocol
M+8
Waveform of the received signal (identical with M06)
5.3 Sensors
Selection of sensor position

32
English
The first step before installation should be finding a suitable position to place the sensors. This is a
requirement for accurate measurement results. Some basic knowledge about the pipes / the
plumbing system is necessary.
The ideal location would be an infinitely long, straight pipe, whereas there must be no entrapped air
(air bubbles) in the liquid. The pipes can either run vertically or horizontally. To avoid inaccuracies
due to turbulence in the liquid, a straight flow-calming section before and behind the measuring point
should be considered. In general, the section in front of the measuring point should be at least 10 x
the pipe diameter and after the measuring point, it should be 5 x the pipe diameter.
The following chart shows examples of good positions:
Pipe routings and sensor position
Upstream
Downstream
Lup x ø
Ldn x ø
10D
5D
10D
5D
10D
5D
12D
5D
20D
5D
20D
5D
30D
5D

33
English
The following should be considered when looking for a good measuring position:
(1) Install the sensors on a preferably long, straight pipe which is completely filled with the liquid
and does not contain any air bubbles.
(2) Make sure that the liquid and thus the pipe is not too hot for the sensors. The temperature
should be as similar to the room temperature as possible.
(3) Consider fouling of the pipes. If possible, choose a clean or new pipe for measurement. You
can also clean the pipe. If this is not possible, consider the thickness of the fouling as part of
the liner.
(4) Some pipes have a synthetic liner. There can be a boundary layer between the outer pipe
and the liner. This boundary layer can divert or weaken the ultrasonic waves, which will
make a measurement very difficult. If possible, these types of pipes should be avoided. If this
is not possible, sensors can also be built into the pipe.
Sensor installation
The UMI 840 has piezoelectric sensors which can transmit and also receive ultrasonic waves. The
time the ultrasonic waves take to pass through the pipe walls and the liquid allows conclusions about
the flow velocity. As the transit time of the ultrasonic pulses is very short, the sensors should be
installed as precisely as possible to ensure highest system accuracy.
Take the following steps to install the sensors:
(1) Some pipes have a plastic liner. There can be a boundary layer between the outer diameter
of the pipe and the inner liner. This boundary layer can divert or weaken the ultrasonic
waves. In this case, an accurate measurement will be very difficult. If possible, these types of
pipes should be avoided.
(2) Find an ideal position in the piping system, i. e. a straight section with new and clean pipes,
if possible.
(3) It is very important that the pipes are clean. Grind or polish the locations where you would
like to place the sensors.
(4) If a pollution cannot be removed, its thickness should be considered as part of the liner of
the pipe.
(5) There must not be an air gap between the sensors and the surface of the pipe. Attach the
sensors using sufficient contact gel.
(6) Moreover, you should make sure there is no dust or sand between the pipe and the sensor.
To avoid air bubbles from causing measurement errors, place the sensors on the pipe
laterally.

34
English
Spacing between the sensors
The distance between the upstream and the downstream sensor can be seen in window M25. The
window states the inner distance between the two sensors which you should stick to as accurately as
possible. The information in M25, however, must only be considered a coarse adjustment. The fine
adjustment is carried out by arranging the spacing in a way that the time constant in M90 is exactly
100%.
To ensure accurate measurement values, the following data must be entered:
(1) Outer diameter of the pipe (M10)
(2) Material thickness of the pipe (M11)
(3) Material of the pipe (M14)
(4) Liner of the pipe (M16)
(5) Type of liquid (M20)
(6) Type of sensors connected (M23)
(7) Mounting method of sensors (M24)
(8) Check the spacing in window M25 and fix the sensors accordingly.
(9) !!! During installation, make sure that the value of the time constant in M90 is 100 %,
that the signal strength is >700 and that the signal quality is >60.
Selection of the measurement method
V method
The V method is the most commonly used method for everyday use. It is ideal for inner pipe
diameters of 20 to 300 mm. It is also called reflective method.
Top view of pipe
1 Upstream transducer
2 Spacing
3 Downstream transducer
4 Flow direction

35
English
Z method
The Z method is recommended for pipe diameters of 300 to 500 mm.
Top view of pipe
1 Upstream transducer
2 Spacing
3 Flow direction
4 Downstream transducer
W method
The W method is suitable for measurements of plastic pipes with diameters of 10 to 100 mm.
Top view of pipe
1 Upstream transducer
2 Spacing
3 Downstream transducer
4 Flow direction

36
English
5.4 Data logger
The internal memory of the device can save up to 1,800 values. (Each item selected in M50 is
considered a value). To set or start the logger, do the following:
(1) Via window M51, you can set the start time, the saving interval and the run time. This
means that measurements can be taken for a maximum of 24 hours.
(2) Window M52 is used to determine where data are saved. According to the standard
setting, the data are saved to the device. You can also transfer the data directly to the RS-
232 / USB interface without saving them to the internal memory.
(3) Via window M50, you can set the logger and select the values you would like to save.
You can view the saved data via window M53.
You can read out the saved data from the buffer via the RS-232 / USB interface and delete the
internal memory using the functions in window M52.
To transfer data to a computer, you will need the software SOFT-UMI.
6 Calibration
There is a (calibration) factor between the real flow velocity and the flow velocity displayed by the
device. This calibration factor can be determined by carrying out a calibration. However, you will
need flow calibration equipment to do so.
Please send the device to Dostmann electronic for calibration. Our contact details can be found at
the end of this manual.
7 Maintenance
7.1 Troubleshooting
Error messages after switching on
The device runs a self-diagnostic programme when switched on. This diagnostic programme is
supposed to find hardware errors. The following chart shows possible error messages.
Error message
Reason
Countermeasure
„ROM Testing Error”
„Segment Test Error”
Software problem
(1) Restart the device
(2) Contact Dostmann
electronic
„Stored Data Error“
The parameters entered by
the user are not integrated
Press the ENTER key. All
values are reset to default.
„Timer Slow Error”
„Timer Fast Error”
Problems with the timekeeper
(1) Restart the device
(2) Contact Dostmann
electronic
„Date Time Error”
Number error in the calendar
Initialise the calendar via
window M61
Repeated reboot
Hardware problem
Contact Dostmann electronic

37
English
Error codes and countermeasures
Error codes are indicated by a single letter in the lower right corner of the display. However, these
only occur in the menus M00, M01, M02, M03, M90 and M08. The following chart shows the error
codes and countermeasures.
Error
code
Message in window
M08
Reason
Countermeasure
R
System Normal
No error
- - -
I
Detect No Signal
(1) No signal
(2) Sensors installed
improperly
(3) Too much fouling
(4) Liner too thick
(5) Sensor cable not
Properly
connected
(1) Change
measuring
location
(2) Clean measuring
location
(3) Check the cables
J
Hardware Error
Hardwareproblem
Contact Dostmann
electronic
H
PoorSig Detected
(1) Schlechtes Signal
(2) Sensoren falsch
angebracht
(3) Zu viel Bewuchs,
zu starke
Verschmutzung
(4) Auskleidung vom
Rohr zu dick
(5) Sensorkabel nicht
korrekt
angeschlossen
(1) Change
measuring
location
(2) Clean measuring
location
(3) Check the cables
(4) Check the
contact gel
Q
Frequ OutputOver
Die
Ausgangsfrequenz
liegt außerhalb des
erlaubten Bereiches
Check the values in
the windows M67,
M68 and M69. Enter
higher values in
window M69.
F
System RAM Error
Date Time Error
CPU or IRQ Error
ROM Parity Error
(1) Vorübergehende
Probleme mit dem
RAM oder RTC
(2) Permanente
Probleme mit der
Hardware
(1) Restart the device
(2) Contact
Dostmann electronic
1
2
3
Adjusting Gain
Das Gerät stellt
gerade die
Signalverstärkung
(Gain) neu ein; die
Zahl gibt den
aktuellen
Arbeitsfortschritt an
- - -
K
Empty pipe
(1) Keine Flüssigkeit
in der Rohrleitung
(2) Einstellungsfehler
im Menü M29
(1) Choose a pipe
that contains
liquid
(2) Enter “0“ in
window M29.
Further errors and countermeasures
(1) When the device indicates 0.0000 even though there is a volume flow and an “R“ glows in

38
English
the display and the signal quality Q is ok, there must be a different error. In many cases, this
means that the zero point has been set incorrectly. Go to menu M432 and reset the zero
point.
(2) The displayed volume flow is obviously too low or too high:
a) Probably, the volume flow in window M44 has been entered manually. Set this value to
“0“.
b) Problems with the sensor installation
c) Possibly, the display was set to “0“ via M42 despite an existing volume flow. Repeat the
zero point setting and make sure that there is no flow in the pipe.
(3) The real battery life is shorter than the value stated in M07.
a) The battery has exceeded its life cycle.
b) The battery has not been charged completely or the charging procedure has been
interrupted too frequently. Charge the battery again. If the problem persists, contact
Dostmann electronic.
c) When the battery voltage is between 3.70 and 3.90 V, discrepancies between the
estimated and the actual transit time can occur.