Continuous level measuring system
NB 4000
Technical information / Instruction manual
page G
Notes for use in Hazardous Locations
ATEX Zone classification
* in case of conductive dust, additional
requirements for installation are
necessary.
Silo wall
inside silo
(process)
outside silo
(ambient)
Zone 22
(Category 3)
Zone 21
(Category 2)
Zone 20
(Category 1)
General notes
Marking
Devices with Ex-approval are marked on the type plate.
Process pressure
The device construction allows process over-pressure up to +0.2bar (2.9psi).This pressure
is allowed for test purposes. The definition of the Ex approvals are only valid for a silo-over-
pressure between -0.2..+0.1 bar (-2.9..+1.45psi).
Outside of these pressure the approvals are not valid.
Process and ambient
temperature
The permitted temperature range is marked on the type plate.
Category
useable in zone
1 D
20, 21, 22
2 D
21, 22
3 D*
22
Permitted zones (categories) for mounting in partition wall
Maximum Surface Temperature
The maximum surface temperature refer to the warmest area outside on the unit which can occur in failure case (according to Ex definition).
Static discharge of the material surface
It must be ensured that no static discharge can occur when the grounded metal sensor weight or rope /tape touches the surface of
the bulk material. If this can not be ensured, the safe use of the unit is NOT guaranteed. The responsibility for this rests with the user.
In case of inclarity an assessment from a notified body is necessary.
From the manufacturer side a version with a plastic sensor weight and additional plastic rope insulation part is available on request.
This keeps a 500mm (19.7") distance from the material surface to the grounded rope/tape.
Max.
ambient
temperature
Max.
process
temperature
Max.
surface
temperature
60°C (140°F)
80°C (176°F)
130°C (266°F)
Nivobob
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NB 4000
gi010413
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