Kobold NBA-2 User manual

Operating Instructions
for
Bypass Level Switch
Model: NBA-2/NBE-2

NBA-2/NBE-2
page 2 NBA-2/NBE-2 K05/1022
1. Contents
1.Contents ........................................................................................................ 2
2.Note .............................................................................................................. 3
3.Instrument Inspection .................................................................................... 3
4.Regulation Use ............................................................................................. 4
5.Operating Principle ........................................................................................ 4
6.Mechanical Connection ................................................................................. 5
7.Electrical Connection .................................................................................... 5
8.Operation ...................................................................................................... 6
9.Hysteresis ..................................................................................................... 6
10.Maintenance ................................................................................................. 6
11.Technical Information .................................................................................... 7
12.Order Codes ................................................................................................. 8
13.Dimensions ................................................................................................... 8
14.Disposal ...................................................................................................... 10
15.EU Declaration of Conformance ................................................................. 11
16.UK Declaration of Conformity ...................................................................... 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

NBA-2/NBE-2
NBA-2/NBE-2 K05/1022 page 3
2. Note
Please read these operating instructions before unpacking and putting 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.
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-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:
 Bypass Level Switch model: NBA-2/NBE-2

NBA-2/NBE-2
page 4 NBA-2/NBE-2 K05/1022
4. Regulation Use
Any use of the Bypass Level Switch, model: NBA-2/NBE-2, 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.
5. Operating Principle
The instrument comprises a metal housing with internally mounted magnetic level
switch and operates on the principle of communicating tubes.
As soon as the housing of the bypass level switch is filled about half way with
liquid, the float moves to the top and operates with the internal ring magnet a
changeover contact fitted in the measuring tube. Solenoid valves, signal lamps or
pumps are switched by the changeover contact by means of suitable electrical
auxiliaries (relay, contactor relay).
The following may have a negative impact on assured functioning:
 Considerable accumulation of dirt
 Large solid parts
 Crystallization
 Ferrite particles

NBA-2/NBE-2
NBA-2/NBE-2 K05/1022 page 5
6. Mechanical Connection
Use the process connection and suitable sealants to respectively bolt and seal
the NBA or NBE instrument to the tank to be monitored. The two process
connections are, as a rule, adequate for mechanically fastening the instrument.
Should there, however, be continuous shocks or pronounced vibrations, then it is
recommended additionally using rubber-absorbent pipe clamps to mechanically
fasten the bypass level switch. But no welding at all is to be done at the bypass
pipe.
7. Electrical Connection
Notice is to be taken of the safe electrical limiting data of the level
switch.
Connect the float switch fitted in the NBA/NBE instrument according to the
connection diagram below and link up to the electrical control system.
At all events it must be ensured when actuating loads such as contactors, relays
etc. that the electrical limiting values are not exceeded – and not even briefly due,
for instance, to voltage peaks. A contact protection relay is recommended to stop
any contact overloading.
14 1
0
12

NBA-2/NBE-2
page 6 NBA-2/NBE-2 K05/1022
8. Operation
Fill tank and switch on the electrical control system, if present. Given stop valves
between bypass process connection and tank, then slowly open the upper valve
(air balance) before the lower valve (liquid-side). Any venting and drain valves are
to be closed before filling starts. The liquid now entering the bypass pipe raises
the float until the level between tank and bypass pipe is evened out. The fact of
the liquid level in the tank already being above the operating point results in the
applied operating signal either being relayed or disconnected - depending on the
electrical connection wiring.
9. Hysteresis
Hysteresis refers to the difference between the cut-in and tripping points of the
contact. Adaptation undertaken at the factory of float magnet and contact strength
has produced a 7 mm float lift hysteresis.
10. Maintenance
Only when the liquid to be monitored has particles of dirt which might settle in the
bypass tank is the drain plug now and again to be undone to flush out any
deposits.
If incrustations or crystallization are present, then the tank must be emptied or
sealed off. This is to be followed by slowly removing the tank lid plus slider tube
and float from the bypass tank. The bypass tank can now be mechanically
cleaned.

NBA-2/NBE-2
NBA-2/NBE-2 K05/1022 page 7
11. Technical Information
Case material: aluminium (NBA)
stainless steel (NBE)
Seal: lid: NBR (NBA), PTFE (NBE)
drain screw: PTFE
Connections: G 3/8 female (NBA)
R ½ male (NBE)
Electrical connection box: aluminium 50x45x30 mm (NBA)
plastic Ø 80 mm (NBE)
Cable gland: M16x1,5
clamp range 5-9 mm
Measuring tube material: stainless steel 1.4571
Float material: stainless steel 1.4571
Medium temperature: -40...+90 °C (NBA)
-40...+150 °C (NBE)
Ambient temperature: -25...+80 °C
Max. pressure: 10 bar
Density of liquid: min. 0.65 kg/dm3
Contact components: 1 changeover contact
Contact material: Rhodium
Switching capacity: max. 60 VA
Switching voltage: max. 250 VAC
Inrush peak: max. 1 A
Hysteresis: approx. 7 mm

NBA-2/NBE-2
page 8 NBA-2/NBE-2 K05/1022
12. Order Codes
Case material Order number
aluminium NBA-200 R 10
stainless steel NBE-200 K 15
13. Dimensions
NBA-2

NBA-2/NBE-2
NBA-2/NBE-2 K05/1022 page 9
NBE-2

NBA-2/NBE-2
page 10 NBA-2/NBE-2 K05/1022
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