Kobold NBK-03 User manual

Operating Instructions
for
Bypass Level Indicator
Model: NBK-03/-06/-07/
-10/-31/-32/-33

NBK
page 2 NBK K06/0623
1. Contents
1.Contents ........................................................................................................ 2
2.Note .............................................................................................................. 3
3.Instrument Inspection .................................................................................... 4
4.Regulation Use ............................................................................................. 5
4.1.Bypass Measuring Tube System ......................................................... 5
5.Electrical connection ..................................................................................... 6
6.Operating Principle ........................................................................................ 6
7.Mechanical Connection ................................................................................. 7
8.Commissioning.............................................................................................. 8
9.Trouble Shooting ........................................................................................... 9
10.Maintenance ................................................................................................. 9
11.Technical Information .................................................................................. 10
12.Order Codes ............................................................................................... 10
13.Dimensions ................................................................................................. 10
14.Disposal ...................................................................................................... 11
15.EC Declaration of Conformance ................................................................. 12
Manufactured and sold by:
Kobold Messring GmbH
Nordring 22-24
D-65719 Hofheim
Tel.: [phone]
Fax: [phone]
E-Mail: [email protected]
Internet: www.kobold.com

NBK
NBK K06/0623 page 3
2. Note
Please read these operating instructions before unpacking and setting the unit
into operation. Follow the instructions precisely as described herein.
The instruction manuals on our website www.kobold.com are always for currently
manufactured version of our products. Due to technical changes, the instruction
manuals available online may not always correspond to the product version you
have purchased. If you need an instruction manual that corresponds to the
purchased product version, you can request it from us free of charge by email
([email protected]) in PDF format, specifying the relevant invoice number and
serial number. If you wish, the operating instructions can also be sent to you by
post in paper form against an applicable postage fee.
Operating instructions, data sheet, approvals and further information via the QR
code on the device or via www.kobold.com
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 measuring unit should be used only when the
machines fulfil the EC-guidelines.
Classification according to Pressure Equipment Directive 2014/68/EU
NBK-03 to NBK-33
Cate
g
or
y
assi
g
nment for dan
g
erous media
(
from dia
g
ram 1
)
Density
[k
g
/dm³]
PN
[bar]
Category ML
[mm]
Category ML
[mm]
Category ML
[mm]
Category ML
[mm]
Category ML
[mm]
NBK-03
1,0
16
← Art.4, Para. 3←
≤317
← Cat. I →
945
← Cat. II →
4711
← Cat. III →
24795 - / -
0,9/0,8/0,7/
0,6/0,54 ≤207 835 4600 24685 - / -
NBK-06
1,0
40
192 1698 9732
← Cat. IV →
∞
0,9/0,8/0,7 82 1588 9622 ∞
NBK-07
1,0
63
------- 128 1060 6504 ∞
0,9/0,8/0,7 ------- 18 950 6394 ∞
NBK-10
1,0
100
------- 140 577 4084 ∞
0,9/0,8 ------- 30 467 3974 ∞
NBK-31
1,0
160
≤2090 5600
0,9 ≤2020 5600
0,8 ≤1900 5400
NBK-32
1,0
250
≤1180 5600
0,9 ≤1110 5600
0,8 ≤985 5400
NBK-33
1,0
320
≤1040 5600
0,9 ≤970 5500
0,8 ≤830 5400
ATTENTION! If the calculated bypass length is exactly within the range limit, then the stricter test method must be used

NBK
page 4 NBK K06/0623
Classification according to Pressure Equipment Directive 2014/68/EU
NBK-03 to NBK-33
Cate
g
o
r
y
assi
g
nment for not dan
g
erous media
(
from dia
g
ram 2
)
Density
[k
g
/dm³]
PN
[bar]
Category ML
[mm]
Kategorie ML
[mm]
Category ML
[mm]
Category ML
[mm]
Category ML
[mm]
NBK-03
1,0
16
← Art.4, Para. 3←
≤945
← Cat. I →
4711
← Cat. II →
24795
← Cat. III →
75007 - / -
0,9/0,8/0,7/
0,6/0,54 ≤835 4600 24685 74897 - / -
NBK-06
1,0
40
≤192 1698 9732 29816 - / -
0,9/0,8/0,7 ≤82 1588 9622 29706 - / -
NBK-07
1,0
63
≤128 1060 6504 20112
← Cat. IV →
∞
0,9/0,8/0,7 ≤18 950 6394 20002 ∞
NBK-10
1,0
100
≤140 577 4084 12849 ∞
0,9/0,8 ≤30 467 3974 12739 ∞
NBK-31
1,0
160
≤2090 5600 - / -
0,9 ≤2020 5600 - / -
0,8 ≤1900 5400 - / -
NBK-32
1,0
250
≤1180 4410 5600
0,9 ≤1110 4340 5600
0,8 ≤985 4220 5400
NBK-33
1,0
320
≤1040 4090 5600
0,9 ≤970 4010 5500
0,8 ≤830 3870 5400
ATTENTION! If the calculated bypass length is exactly within the range limit, then the stricter test method must be used
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:
 Bypass Level Indicator model: NBK

NBK
NBK K06/0623 page 5
4. Regulation Use
Any use of the Bypass level Indicator, model: NBK, which exceeds the
manufacturer’s specification may invalidate its warranty. Therefore, any resulting
damage is not the responsibility of the manufacturer. The user assumes all risk
for such usage.
The NBK Bypass Level Indicator is used for continuous measurement, indication,
and monitoring of liquids in tanks, vessels, reservoirs, basins etc. The indication
occurs via a magnetically coupled roller indicator.
4.1. Bypass Measuring Tube System
The bypass tube is attached at the side of the vessel with a connecting flange or
a threaded pipe. The installation position is always vertical. The NBK should only
be used for liquids with the medium density specified on the nameplate.
Otherwise, the indication will deviate (float too high or submerged).
Vessel inner pressure and medium temperature should not exceed the specified
maximum values, as this can lead to the destruction and malfunction of the
bypass system. It is imperative that the materials used are compatible with the
liquid being measured.
Proper operation is also impaired by:
 High degree of soiling
 Suspended solids
 Crystallisation
 Ferrite particles

NBK
page 6 NBK K06/0623
5. Electrical connection
Optional electrical add-on parts (transmitter and limit contacts)
There is a separate operating manual for the assembly and commissioning of the
optional electrical add-on parts: MM, NMT/NBK-T, NBK-R
These operating instructions document the following electrical add-on parts:
Transmitter:
Reed contact resistor chain model W
Reed contact resistor chain with transmitter model M
Magnetostrictive sensor with transmitter model T
Reed contact resistor chain with transmitter model AE/AC
Reed contact resistor chain with transmitter HART model HE/HC
Reed contact resistor chain with transmitter FF model F
Limit Contacts:
Reed switch limit contact model NBK-R
Limit contact high temperature model NBK-RT200/RT400
Reed switch limit contact model NBK-RV200NO/RV200NC
Reed switch limit contact NAMUR model NBK-RV200NO/RV200NC
6. Operating Principle
Kobold Bypass Level Indicators are used for continuous measurement, display
and monitoring of liquid levels. The bypass tube is attached onto the side wall of
the vessel. According to the law of communicating tubes the level in the bypass
tube equals the level in the vessel. A float with embedded circular magnets in the
bypass tube follows the liquid level and transfers it in a non-contacting manner to
a display fitted outside the tube or to a monitoring device. The following indication
and monitoring devices are available:
Magnetic roller indicator
As the float passes by, the red/white* rollers/balls are rotated in succession by
180° around their own axes. The rollers change from white to red as the level
rises and from red to white as the level falls. The advantage of ball displays is the
higher protection category, good visibility of 180 ° and higher vibration resistance
with filled version. The level in a tank or a mixer is continuously displayed as a
red column, even when the power supply fails.
* ceramic rollers in orange/beige

NBK
NBK K06/0623 page 7
7. Mechanical Connection
Remove bottom flange from bypass
tube, and insert the cylindrical float in
the NBK bypass tube with the
designation "TOP" at the top. Re-
position the gasket and close the
bottom flange again; firmly tighten with
screws.
Mount the bypass tube to the vessel to
be monitored via the process
connection and seal with an
appropriate device. Normally it is
sufficient to fix the complete NBK with
both process connections. However,
should the NBK be subjected to
constant shock or strong vibrations it
is recommended that the instrument is
secured with rubber-damped tube
clips. No welding is allowed on the
bypass tube.
Mount and tighten the magnetic roller
indicator - if not already mounted - on
the bypass tube with the two provided
ribbon clamps.

NBK
page 8 NBK K06/0623
8. Commissioning
Because of the setting behaviour of seals, all screw connections must be
retightened.
Fill vessel and switch on electrical controller, if available. If there are gate valves
between bypass process connection and tank, first slowly open the upper valve
(pressure relief) and then the lower valve (liquid side). If vent and drain valves
have been installed, close them before filling.
The liquid that now enters the bypass tube raises the float until the level between
tank and bypass tube is balanced. The roller indicator indicates the liquid level.
For media with high operating temperatures, the surface of the level
indicator also heats up. The operator must take appropriate measures to
prevent accidental contact with such surfaces (protective cage). If this is
not structurally possible under certain conditions, appropriate protective
clothing must be worn in the area of the level indicator.

NBK
NBK K06/0623 page 9
9. Trouble Shooting
Error: The tank is full but there is no indication
 Check that both flanges (process connection), top and bottom, are open to the
vessel, and that the bypass tube fills with liquid.
 Check that there is a float in the system.
 When the float is installed, check whether it is being blocked by foreign objects
or dirt deposits.
Error: The tank is full but the indication is too low.
 Check that the density of the liquid is the same as the density given on the
nameplate.
 Check that the float has been correctly installed with the marking "TOP" at the
top.
 Check if dirt deposits in the bypass tube are blocking the float.
10. Maintenance
The drain plug should be opened occasionally, to wash out any deposits in case
the liquid to be measured contains dirt particles, which could settle in the bypass
tube.
If crust formation or crystallisation has taken place, the tank must be emptied or
shut off; the lower cover flange must then be removed. The float should then be
removed carefully out of the bypass. The bypass tube can now be mechanically
cleaned.
The inspection window for the roller indication is made of high-quality plexiglass
(glass for high-temperature display). It should be cleaned with a suitable cleaning
agent.
The indicator requires no further maintenance.

NBK
page 10 NBK K06/0623
11. Technical Information
Operating instructions, data sheet, approvals and further information via the QR
code on the device or via www.kobold.com
12. Order Codes
Operating instructions, data sheet, approvals and further information via the QR
code on the device or via www.kobold.com
13. Dimensions
Operating instructions, data sheet, approvals and further information via the QR
code on the device or via www.kobold.com

NBK
NBK K06/0623 page 11
14. Disposal
Note!
 Avoid environmental damage caused by media-contaminated parts
 Dispose of the device and packaging in an environmentally friendly
manner
 Comply with applicable national and international disposal regulations and
environmental regulations.
Batteries
Batteries containing pollutants are marked with a sign consisting of a crossed-out
garbage can and the chemical symbol (Cd, Hg, Li or Pb) of the heavy metal that
is decisive for the classification as containing pollutants:
Cd1 Hg2 Pb3 Li4
1. „Cd" stands for cadmium
2. „Hg" stands for mercury
3. „Pb" stands for lead
4. „Li" stands for lithium
Electrical and electronic equipment

NBK
page 12 NBK K06/0623
15. EC Declaration of Conformance
We, KOBOLD Messring GmbH, Hofheim-Ts, Germany, declare that the Bypass
Level Indicators fulfil the following standards:
Model Pressure
sta
g
e
Category
as per PED
EC type
examination test
NB
K
-03 PN 16 III PEDB000004D
NB
K
-06 PN 40 III PEDB000004D
NB
K
-07 PN 63 III PEDB000004D
NB
K
-10 PN 100 IV PEDB000004D
NB
K
-31 PN 160 IV PED-B-171
NB
K
-32 PN 250 IV PED-B-171
NB
K
-33 PN 320 IV PED-B-171
and are in conformity with the standards noted below:
EN IEC 63000:2018 Technical documentation for the assessment of electrical
and electronic products with respect to the restriction of hazardous substances
Also, the following EC guidelines are fulfilled:
2011/65/EU RoHS (category 9)
2015/863/EU Delegated Directive (RoHS III)
2014/68/EU PED
 Category III (IV) Diagram 1, vessel, group 1 dangerous
fluids
 Module D, marking CE0575
 Notified body: DNV AS
 Certificate No. PEDD000000R
Hofheim, 21 Feb. 2023
H. Volz M. Wenzel
General Manager Proxy Holder