Nivobob
®
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NB 3000
gi130109
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Continuous level measuring system
NB 3000
Technical information / Instruction manual
page G
Introduction
The Nivobob
®
NB 3000 is an electromechanic level
measuring
instrument for continuous measuring of level or volumes in silos,
hoppers or tanks.
Applications
•
Powder, granulate, small or coarse bulk goods
•
Interface measurement (solids in water)
Applicable for industries such as
• Chemistry
• Food
• Cement
• Mining
• Plastics
• others
Features
Process
•
Suitable for most types of bulk goods
• Independent of bulk material properties, such as:
Dielectricity and conductivity of the bulk good
Dusty atmosphere in the silo
Changing humidity inside the product
Products that tend to stick
•
No mechanical load on the silo roof, the sensor weight
just touches the surface of the material
•
Very accurate measurement
Service
•
Simple installation and commissioning
•
Measurement principle easy to understand
• Rope, tape and (optional) motor with increased service life
• Low maintenance
Approvals
•
Approval for use in Hazardous Locations
ATEX II 1/2 D (zone 20/21) and FM Class. II, III Div.1 Gr. E-G
Mechanic
• Measurement range upto 40m (133ft)
• 1 1/2" process connection possible
•
Different sensor weights, suitable for every application
•
Internal tape cleaner for difficult materials
• Window in lid and external start button (optional)
•
Robust cast housing, ingress protection IP66
Electronic
•
Micro processor controlled measurement
• Remote Box for external programming, display of level and
diagnose, start of measurement of up to 10 Nivobob units
• Comprehensive Diagnose possibilities
•
Output 0/4-20mA / Modbus / Profibus DP / counting pulses
• Programmable relais (can be used as level limit switch outputs)
• Measurement start with external signal or integrated timer
Function
The Nivobob
®
NB 3000 is mounted on the top of the silo. A sensor
weight is driven down into the silo. It is mounted at the end of a rope
or tape which is wound on a motor driven roller. Upon contact with
bulk material, the motor changes the winding direction and the sensor
weight is driven back to the upper stop position.
During downwards movement of the sensor weight the distance is
electronically measured by the rotations of the internal rope / tape
roller. The microcontroller converts the measured distance into an
output signal, which is a volumetric signal based on the silo geometry.
The output signal is updated, when the sensor weight touches the bulk
material.
Diagnostics
Comprehensive diagnostics possibilities are present:
• Measurement control is done by comparing the moved distance
between up and downward movement and checking for discrepancy.
In case of discrepancy, the sensor weight is pulled to the upper stop
position to ensure, that the sensor weight is not inside the silo.
• Service interval after a certain amount of measurements and running
time.
• Internal control of motor, motor driver electronic and smooth
movement of rope / tape rollers.
Diagnostics is in accordance with NAMUR recommendation NE107.
