Kobold NUS-4x04, NUS-4x06, NUS-4x08, NUS-4x15, NUS-4x25 Instruction Manual

Instruction Manual

for

Ultrasonic Level Meter

Model: NUS-4...

NUS-4

Seite 2 NUS-4 K05/0216

1. Contents

1. Contents ........................................................................................................ 2

2. Note .............................................................................................................. 4

3. Instrument Inspection .................................................................................... 4

4. Regulation Use .............................................................................................. 4

5. Operating Principle ........................................................................................ 5

6. Mechanical connection .................................................................................. 5

6.1 Block distance ...................................................................................... 5

6.2 Installation (Liquid Level Measurement) .............................................. 6

6.3 Installation (Open Channel Flow Measurement) .................................. 7

6.4 Mechanical connection ........................................................................ 8

7. Electrical Connection .................................................................................... 8

8. Programming ................................................................................................ 9

8.1 BASIC CONCEPTS AND ELEMENTS OF THE ULTRASONIC

MEASUREMENT ................................................................................. 9

8.2 Programming without Display Module .................................................. 9

8.3 Programming with the Display Module NUS-400P ............................ 11

8.3.1 Display Module NUS-400P ........................................................ 12

8.3.2 Programming steps with the Display Module NUS-400P ........... 13

8.3.3 GET LEVEL Function ................................................................ 14

8.3.4 INDICATIONS OF THE NUS-400P AND LED STATUS ............ 14

8.3.5 QUICKSET ................................................................................ 15

8.3.6 Full Parameter Access ............................................................... 17

9. Parameters – Description and Programming .............................................. 18

9.1 Measurement Configuration ............................................................... 18

9.2 Current Output ................................................................................... 21

9.3 Relay Output ...................................................................................... 22

9.4 Measurement Optimisation ................................................................ 23

9.5 Volume Measurement ........................................................................ 26

9.6 Volume Flow Measuring .................................................................... 27

9.7 32- Point Linearisation ....................................................................... 31

9.8 Informational Parameters (Read Out Parameters) ............................ 32

9.9 Additional Parameters of Flow Metering in Open Channels ............... 33

9.10 Test Parameters ................................................................................ 33

9.11 Simulation .......................................................................................... 33

9.12 Access Lock ....................................................................................... 34

10.Error Codes ................................................................................................. 34

11.Parameter Table ......................................................................................... 35

12.Sound Velocities in Different Gases ............................................................ 36

13.Technical Data ............................................................................................ 37

14.Order Codes ............................................................................................... 38

15.Dimensions ................................................................................................. 39

16.EU Declaration of Conformance .................................................................. 40

NUS-4

NUS-4 K05/0216 Seite 3

Manufactured and marketed by:

Kobold Messring GmbH

Nordring 22-24

D-65719 Hofheim

Tel.: [phone]

Fax: [phone]

Internet: http: //www.kobold.com

e-mail: [e-mail]

NUS-4

Seite 4 NUS-4 K05/0216

2. Note

Please read these operating instructions before unpacking and putting the unit into
operation. Follow the instructions precisely as described herein. The devices are
only to be used, maintained and serviced by persons familiar with these operating
instructions and in accordance with local regulations applying to Health & Safety
and prevention of accidents.

When used in machines, the NUS should be used only when the machines fulfil the
EC-machine guidelines.

3. Instrument Inspection

Instruments are inspected before shipping and sent out in perfect condition. Should
damage to a device be visible, we recommend a thorough inspection of the
delivery packaging. In case of damage, please inform your parcel service /
forwarding agent immediately, since they are responsible for damages during
transit.

Scope of delivery:

The standard delivery includes:

 Ultrasonic level meter model: NUS-4
 Instruction Manual

4. Regulation Use

Model NUS-4 is a compact user friendly ultrasonic level meter comprising of an
ultrasonic sensor and an integrated evaluating electronics. It was specifically
developed for level and volume measurement in open and closed vessels or for
flow measurement in open channels.

Level measurement technology based on the non-contacting ultrasonic principle is
especially suited for applications where, for any reason, no physical contact can be
established to the surface of the material to be measured.

Such reasons may include corrosive attack by the process medium against the
measuring device material (acids), possible contamination (sewage) or particles of
the process medium adhering to the measuring device (adhesive materials).

NUS-4

NUS-4 K05/0216 Seite 5

5. Operating Principle

The sensor emits an ultrasonic pulse train and receives the echoes reflected. The
intelligent electronic device processes the received signal by selecting the echo
reflected by the surface and calculates from the time of flight the distance between
the sensor and the surface. A Norm signal output is available for remote transfer
whereas a relay contact is available for monitoring purpose.
A narrow beam angle ensures a reliable measurement in narrow silos with uneven
side walls as well as in process tanks with various protruding objects. Furthermore,
as a result of the narrow beam angle - the emitted ultrasonic signals have an
outstanding focusing - deep penetration through gases, vapour and foam is
ensured.

6. Mechanical connection

6.1 Block distance

Due to signal characteristics of the sensor, there is an area directly below the
sensor, where no pulses can be received (Dead Zone).
The so called Block distance (minimum measuring distance) is very important for
error free functioning of the level meter. It determines the minimal distance
between the sensor and maximum level. This distance can be extended by
programming in order to avoid disturbing effects of possible disturbing echoes
coming from fixed objects (Close-end Blocking).

 Mount the sensor high enough that even with maximum filling of the container,

the block distance is not violated. Violation of the block distance may lead to
device-malfunction.

Model Block distance

NUS-4x04

0,20 m

NUS-4x06

0,25 m

NUS-4x08

0,35 m

NUS-4x10

0,35 m

NUS-4x15

0,45 m

NUS-4x25

0,60 m

NUS-4

Seite 6 NUS-4 K05/0216

6.2 Installation (Liquid Level Measurement)

 Never mount two ultrasonic level-measuring devices in one container,

because the two devices can interfere with each other's functioning.

POSITION

The optimal position of the NUS-4 is on
the radius
r = (0.3 … 0.5) R of the (cylindrical) tank
/ silo.
(Take also sonic cone on page 39 into
consideration.)

SENSOR
ALIGNMENT

The sensor face has
to be parallel to the
surface of the liquid
within  2-3.

TEMPERATURE

Make sure that the
transmitter will be
protected against
overheating by direct
sunshine.

Sunshade

OBSTACLES

Make sure that no in­flow path or objects
(e.g. cooling pipes,
ladders, bracing
members,
thermometers, etc.) or
no tank wall of the
ragged surface
protrude into the
sensing cone of the
ultrasonic beam.
One fix object in the
tank / silo that disturb
the measurement can
be blocked out by the
optional programming
unit.

FOAM

Foaming of the liquid surface may render ultrasonic level
metering impossible. If possible, a location should be found,
where foaming is the least (device should be located as far
as possible from liquid inflow) or a stilling pipe or well should
be used.

WIND

An intensive air (gas) movement in the vicinity of the
ultrasonic cone is to be avoided. A strong draft of wind may
"blow away" the ultrasound.
Devices with lower measuring frequency (40, 20 kHz) are
recommended.

FUMES / VAPOURS

For closed tanks containing chemicals or other liquids, which
creates fume/gases above the liquid surface especially for
outdoor tanks exposed to the sun, a strong reduction of the
nominal measuring range of the ultrasonic device is to be
considered during device selection.
Devices with lower measuring frequency (40, 20 kHz) are
recommended in these cases units.

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NUS-4 K05/0216 Seite 7

STAND-OFF PIPE

The structure of the stand off pipe should be rigid; the inner rim where the ultrasonic beam leaves the
pipe should be rounded.

L

Ø D

r

L

D

min

r

Ø D

L

L

D

min

NUS-

4x04

NUS-

4x06

NUS­4x08

NUS-

4x10

NUS-

4x15

NUS­4x25*

150 50 60 60 90 80 130 ­200 50 60 75 200 80 140 ­250 65 65 90 350 85 150 ­300 80 75 105 500 90 160 ­350 95 85 120

L

Ø D

L

D

min

NUS-4x10 NUS-4x15

90 80 130
200 80 140
350 85 150
500 90 160

*NUS-4x25
mut not be mounted on a pipe socket, since the sensor surface should protrude into the vessel

6.3 Installation (Open Channel Flow Measurement)

 For ultimate accuracy, install the sensor as close as possible above the

expected maximum water level (see minimum measuring range).

 Install the device in a place defined by the characteristics of the metering

channel along the longitudinal axis of the flume or weir.

 In some cases foam may develop on the surface. Make sure that the surface,

opposite to the sensor remains free of foam for proper sound reflection.

 From the point of view of measurement accuracy the length of the channel

sections preceding and following the measuring flume and their method of
joining to the measuring channel section are of critical importance.

 Despite of the most careful installation, the accuracy of flow metering will be

lower than that of specified for the distance measurement. It will be determined
by the features of the flume or weir applied.

NUS-4

Seite 8 NUS-4 K05/0216

6.4 Mechanical connection

 Screw the unit in to its place. Use open wrench for

tightening; max torque is 20Nm

 After tightening the enclosure can be rotated to the proper

position. (Safety bolt prevents rotation more than 350°)

7. Electrical Connection

 Ensure that the power supply is turned off at the source.
 The unit may be damaged by electrostatic discharge (EDS) via its terminal, thus

apply the precautions commonly used to avoid electrostatic discharge e.g. by
touching a properly grounded point before removing the cover of the enclosure.

 With removal of the cover of the housing and taking out the display module (if

any), the screw terminals can be accessed. Suggested cable core cross section:

0.5 ... 1.5 mm2. Arrange grounding by the inner or outer grounding screw first.

 Switch on the unit and make necessary programming.
 The actual loop current can be measured with an accuracy of 0.5% by

connecting an voltmeter (in the range of 200 mV) to the points indicated on the
drawing

 After programming ensure proper sealing and closing of the cover.

2

1

NUS-4

NUS-4 K05/0216 Seite 9

8. Programming

8.1 BASIC CONCEPTS AND ELEMENTS OF THE ULTRASONIC
MEASUREMENT

Programmed

measurement

range of the
application

P06
Far end blocking

DIST= distance (measured)

Close end blocking (programmed value

LEV= level calculated; H - DIST)
VOL= volume (calculated from DIST LEV)



Max measuring distance of the application (H)

Max measuring distance of the device

DEFAULT value of P04

X

M

Max measurement range of the device

Min measuring distance

(dead band)

DEFAULT value of P05

programmed value of P04

X

m

8.2 Programming without Display Module

Programming is only possible if the Transmitter is in Level Measuring Mode and
receives valid echo i.e. “VALID” LED is lit!
The following can be programmed without display module

 Assignment of the 4 mA to a required e.g.

min. level / max. distance

 Assignment of the 20 mA to a required e.g.

max. level / min. distance

 Error indication by the current output (Hold,

3.6 mA or 22 mA)

 Damping (10, 30 or 60 sec)
 Reset to the factory default

Note:
Current output can also be assigned in inverted mode:
4 mA = 100 % (Full), 20 mA = 0 % (Empty)

NUS-4

Seite 10 NUS-4 K05/0216

Procedure of programming: press button in the relevant sequence and check the

state of the LED-s. Symbols for the states of the LED-s:

= LED is off, = LED is blinking, = LED is on, = LEDs are blinking

alternatively = Dont care

Minimum level, (0%, empty tank) assignment to 4 mA

Place the sensor at a distance to an object corresponding to the maximum
distance/ the minimum level.

Action Led state following the action

B

B

Use level in tank or a fix target e.g.

the wall

1) Check for a valid ECHO

= Valid ECHO, transmitter

programmable

2) Press NEXT button
steadily

= NUS-4 in programming mode

3) Press UP button
steadily

= 4 mA assigned to the distance

(see picture)

4) Release buttons = Programming completed

Maximum Level, (100 %, full tank) assignment to 20 mA)

Place the sensor at a distance to an object corresponding to the minimum
distance/ the maximum level.

Action Led state following the action

B

B

Use level in tank or a fix target e.g.

the wall

1) Check for a valid ECHO

= Valid ECHO, transmitter

programmable

2) Press NEXT button
steadily

= NUS-4 in programming mode

3) Press DOWN button
steadily

= 20 mA as signed to the distance

(see picture)

4) Release buttons = Programming completed

“Error state” indication by the analogue signal (Check for a valid echo as

above)
As a result of this setting the value of the analogue output will be 3.8 mA; 22 mA or
according last value (hold) until the error is ceased.

Action Led state following the action

1) Press button steadily = NUS-4 in programming mode

2) Press any of the DOWN ,
ENTER

E

, NEXT buttons

steadily

– hold last value

= – 3.6 mA

– 22 mA

3) Release buttons = Programming completed

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NUS-4 K05/0216 Seite 11

Damping time setting (Check for a valid echo as above)

Action Led state following the action

1) Press ENTER E button

steadily

= NUS-4 in programming mode

2) Press any of the NEXT
, UP , DOWN

buttons steadily

– 10 sec

= – 30 sec

– 60 sec

3) Release buttons = Programming completed

RESET: Returning to the default (Check for a valid echo as above)

Action Led state following the action

1) Press NEXT button
steadily

= NUS-4 in programming mode

2) Press ENTER E button
steadily

= Default loaded

Indication of mistakes (by LEDs) made during programming

Action Led state following the action Possible correction

Attempted programming = blinking twice = no Echo Find a valid Echo

Attempted programming = blinking three times = no access

possible

With NUS-400P only See 8.3 (P99)

Attempted programming

= blinking four times = NUS-4 not in

Level Measurement Mode

With NUS-400P only See 8.3 (P01)

8.3 Programming with the Display Module NUS-400P

All features of the unit can be set, such as measurement configuration and
optimisation, 32-point linearisation, dimensions for 11 tanks with different shape
and for 21 different open channels (flume, weir, etc).

Devices with the type number NUS-xxxx xx xxP are already equipped with the
display module.

The NUS-4 is also fully operational without display module. The module is only
needed for programming and/or displaying measurement values.

The unit will measure during programming in accordance with the previous
parameters. The new, modified parameters will only be effective after returning to
the Measurement Mode

If the transmitter is left in Programming Mode by mistake, it will automatically return
to Measurement Mode after 30 minutes and will operate with the parameters
entered during the last completed programming.

NUS-4

Seite 12 NUS-4 K05/0216

The NUS-4 will be delivered with the following Factory Default:

 Current output, display and bargraph: LEVEL
 Current output and bargraph proportional to the level
 4 mA: assigned to the minimum level 0 %
 20 mA: assigned to the maximum level 100 %
 Error indication by the current output: hold last value
 Damping: 60 sec

The display module supports two separately accessible programming modes
representing 2-layers of programming complexity, depending on user choice.

PLUG-IN DISPLAY MODULE

QUICKSET

FULL

PARAMETER

ACCESS

8.3.1 Display Module NUS-400P

Symbols used on the LCD

 DIST – Distance

(measuring) mode



LEV – Level (measuring)

mode



VOL – Volume

(measuring) mode



FLOW – Open channel

(flow metering) mode



PROG - Programming

mode (device under
programming)



RELAY – ‘C2’ circuit of

the relay is closed

 T1 - TOT1 volume flow

totaliser (resetable
aggregate)

 T2 - TOT2 volume flow

totaliser (aggregate)



FAIL - Measurement /

device error

  - Level changing

direction
Bargraph assigned to the current
output or echo strength

Symbols used on the frame

 M – Metric system



US – US calculation

system

LEDs lit

 VALID – presence of

valid echo