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MBA888
Level switch
for bulk materials
Installation, operation
MBA Instruments GmbH
Friedrich-List-Str. 5
D-25451 Quickborn
Germany
Telephone +49 (0) 4106 123 8888 – 0
Fax +49 ( 0) 4106 123 888 – 9
[email protected]
www.mba-instruments.de
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Operating instructions MBA888
Operating instructions MBA888
09/2015
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MBA Instruments GmbH
Safety information - for use in areas at risk of explosion (Ex Zones) 1.
A level indicator of type MBA888 is only suitable for use in potentially explosive areas if the individual device specification
permits this.
Check device on the basis of the type plate for approval (ATEX).
An approved device bears the identification:
II 1/2 D Ex ta/tb IIIC T100°C Da/Db
A suitable safety fuse with min. 1500A switch-off delay must be connected upstream.
Observe the specifications of the approvals. The EC type examination certificate is an integral part of the operating
instructions.
Install equipotential bonding lead.
Prevent sparks forming due to striking metal parts.
Perform installation in accordance with the standard EN 60079-14
Observe zone separation (see section 3)
Only lay electrical installations in a suitable terminal enclosure.
The enclosure must not be opened.
With process temperatures in excess of 60°C it is necessary to implement suitable measures, to ensure that the enclosure
temperature does not exceed a temperature of 60°C at the cable connection point at this process temperature.
Responsibility of the user 2.
Only use the device in the manner described in these operating instructions. The manufacturer accepts no responsibility
and provides no warranty cover in case of any other uses.
In addition to these operating instructions, also observe all local laws, technical rules and internal company instructions
that apply at the place of use of the device.
Observe the specifications regarding voltage and temperature on the type plate.
Use 3.
The MBA888 is used as a level switch for all types of bulk materials. The device is only intended for fixed installation in
industrial plants (large tools). The device is designed for zone 21. Furthermore, the shaft end and blade can be fed into zone
20, if a partition wall is installed over the process connection and the requisite leak-tightness is established with the
installation. The leak-tightness of the process connection in terms of the zone separation has not been tested within the
framework of EC type testing and must be ensured by the user.
Conformity: 4.
Explosion protection, general requirements: ...................... EN 60079-0 :2012
Device dust explosion protection through enclosure "t" .... EN 60079-31:2014 + A11:2013
EMC .... ................................................................................. EN 61000-6-4: Sept. 2011 (industrial area)
.................................................................... ........................ EN 61000-6-2: March 2006 (industrial area)
Vibration: .................................... ........................................ IEC 60068-2-6, IEC 60068-2-27
Low voltage: .................................................................... .... EN 61010-1: 2011
Protection level Da for
dust Ex Zone 20, 21 or 22
max. 80°C
Protection level Db for
dust Ex Zone 21 or 22
max. 60°C
Zone separation
Process connection seal:
Klingersil C-4400
60 x 49 x 2 mm
Undercut per DIN 509-E
Process connection G 1 ½"
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Operating instructions MBA888
Operating instructions MBA888
09/2015
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MBA Instruments GmbH
Function and switching behaviour 5.
A motor turns a shaft, which has a blade fastened to its end. If the blade meets with the bulk material, the torque increases
until the shaft stops. The shaft then changes rotational direction. If the shaft is blocked in both rotational directions then
this switches signal
"Quick Switch" device version:
With this version, the MBA888 only checks for a blocking of the shaft rotation in one direction. Very rapid switching as a full
indicator is therefore possible:
Assembly 6.
The MBA888 is bolted with the process connection in a fitting sleeve. The assembly position must be selected such that the blade
on the shaft end is covered by bulk material at the switching point. Light or fluid bulk material must cover the blade somewhat
more than heavy bulk material. The measurement is independent of the installation position of the MBA888.
For use in accordance with II 1/2 D zone separation must be observed (see section 3)
2. Shaft
stops
3. Shaft
rotates to the right
4. Shaft stops
Signal switches
1. Shaft
rotates to the left
+3s
+3s
2. Shaft
stops
3. Shaft stops
Signal switches
1. Shaft
rotates to the left
+1s
light bulk material
moderately heavy bulk material
heavy bulk material
Examples
Washing powder,
Barley,
Plastic granulate
Siliceous sand,
Gravel
Container cover
4 assembly surfaces for
width across flats 65mm
Tightening torque: 300Nmm
Container wall
Screw-in sleeve: G1 ½" per ISO 228/1
Equipotential bonding:
for earthing screw
with eyelet, d=4mm
Process connection G 1 ½"
Process connection seal:
Klingersil C-4400
60 x 49 x 2 mm
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Operating instructions MBA888
Operating instructions MBA888
09/2015
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MBA Instruments GmbH
Installation of MBA888 24V DC 7.
The MBA888 is supplied with a prefabricated cable. The strands on the cable ends are numbered 1 to 4 and must be
laid in a suitable terminal compartment. The housing is integrated in the equipotential bonding.
The cable must be permanently installed!
Terminal compartment with cable infeed for Ø7 - 12mm
Strand
1 24 V DC ±10% operating voltage
2 0 V
3 Signal: 24V full / 0V empty, max. current: 1.2A
4 Ready for operation: 24V operation / 0V fault
Output signal
Strand 1 – 3 Behaviour Cause
+24V DC Shaft rotates Container is empty
0V Shaft does not rotate Container is full
Operation monitoring
Strand 1 – 4 Operating status Measures
+24V DC Function is OK none
0V Function error Function test required
Installation of MBA888 115 - 230V AC 8.
The MBA888 is supplied with a prefabricated cable. The strands on the cable ends are numbered 1 to 5 and must be
laid in a suitable terminal compartment. The housing is integrated in the equipotential bonding.
The cable must be permanently installed!
Terminal compartment with cable infeed for Ø7 - 12mm
Strand
1
115V - 230V AC operating voltage
2
N
3
Relay for main contact
4
Relay for switch contact 1
5
Relay for switch contact 2
The relay switches as a changeover. The contacts are potential-free.
Output signal
Strand 3 – 4 Strand 3 – 5 Behaviour Cause
Closed Open Shaft rotates Container is empty
Open Closed Shaft does not rotate Container is full
Safety-oriented switching as a full indicator
If the MBA888 detects a malfunction or the operating voltage fails then its relay drops out and the status "Container is
full" is indicated.
Maintenance 9.
The MBA888 is maintenance-free. However, the function should be checked regularly and at least 1x yearly.
24V DC version
115 - 230 V AC version
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Operating instructions MBA888
Operating instructions MBA888
09/2015
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MBA Instruments GmbH
Operating data 10.
MBA888 – 24V DC version MBA888 – 115V - 230V AC version
Operating voltage: 24V DC 115V - 230V AC
Power consumption: max. 750mA + current at the signal
output
8W
Signal: 24/0 V DC max. 1.2A Potential-free changeover
Operation monitoring: 24/0 V DC max. 1.2A see "safety-oriented switching"
Connection cable: LAB Ölflex Classic 400P 4x0.5mm
2
Standard length: 2m (other lengths on
request)
LAB Ölflex Classic 400P 5x0.5mm
2
Standard length: 2m (other lengths on
request)
Process temperature in the container (Ti): -20 to +80°C
Ambient temperature (Ta): -20 to +60°C
Ambient pressure: 0.8 to +1.1bar
Enclosure protection type: IP65 – watertight and dust-tight
Shaft Ø12mm, stainless steel 1.4301
Immersion depths: 120mm or 180mm or 250mm
Blade: Stainless steel, welded to the shaft
Seals: VITON and PTFE gasket
Motor shaft additionally sealed (VITON)
Enclosure: Aluminium or stainless steel
Switch time
Standard Quick
Switch
if shaft is blocked: 6s 1s
if shaft is clear: 3s 3s
Ex identification
II 1/2 D Ex ta/tb IIIC T100°C Da/Db
Type examination certificate
ZELM 15 ATEX 0547 X
Type plate (example) 11.
Serial number:
Please always quote
with inquiries
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Operating instructions MBA888
Operating instructions MBA888
09/2015
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MBA Instruments GmbH
Dimensions 12.
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