MBA MBA100 User manual

MBA100
Diaphragm Switch
User Manual
EN

MBA100 User Manual, 2022-02, number 8011706, page 2/4 MBA Instruments GmbH
1. Safety instructions
Use in potentially explosive atmospheres
The type MBA100 level indicator can only be used in potentially explosive
atmospheres if the individual equipment specification permits this.
•Check device by means of type plate and accompanying papers with
regard to approvals (ATEX / CSA).
•Observe the stipulations of the approvals.
•Install with equipotential bonding.
•Avoid sparking through striking of metal parts.
•Carry out the installation per standard EN 61241-14
•Observe the stipulations of the EC type test certificate.
In the event of any doubts regarding the suitability of the
device for a particular application: Contact the manufacturer!
Electrical connection
WARNING: Open contacts inside the device
The electrical contacts inside the device are not protected
against accidental contact. Switch off any signal voltage that may be
connected externally before opening the head of the device.
•Have the device installed and commissioned only by specialists
•The connection diagram is located inside the cover.
•Only use connecting cable that is suitable for the cable inlets.
•The device head and the cable inlets must be closed during operation.
Responsibility of the operator
•Only use the device in such a way as described in these operating
instructions. The manufacturer accepts no responsibility and provides no
warranty for any other use.
•All local laws, technical regulations and company-internal operating
instructions that apply in the locale where the device is used, are to be
observed in addition to these operating instructions.
•Do not remove, insert or alter any components in or on the device insofar
as this is not described and specified in official information from the
manufacturer.
•In potentially explosive areas: Observe European standard EN 61241-14
before installation or operation.
•Observe the specifications regarding voltage and temperature on the type
plate.
2. Functional principle
Membrane switches are employed as limit switches for all types of bulk
solids. The device is only to be used for fixed installation in industrial
systems (large-scale tools). Primarily these would be employed as simple
detectors on conveyor belts, transfer stations, downpipes and anywhere
that a measurement device cannot project into the container.
The product rising in the container presses against the membrane and with
the help of a transfer mechanism a microswitch is actuated. The MBA100
works in a purely mechanical manner and requires no auxiliary power.
3. Dimensions
Hole circle: 189 mm
Bolt holes: 6
Hole diameter: 7 mm
Membrane diameter: 175 mm
For special flange sizes see additional drawing.
4. Installation
The MBA100 is installed on a silo mounting flange. In doing so the
membrane should be connected as flush as possible with the inner wall of
the silo. The flange surfaces of the MBA100 and the container flange are
sealed with the accompanying flat gasket. The fastening of the flange is
implemented with 6 bolts with a diameter of 6mm. When mounting onto a
coupling adaptor care must be taken to ensure that the pressing force of the
bulk solids on the membrane is sufficient to guarantee the MBA100
switching reliably. The maximum length of an adaptor depends on the
properties of the bulk solids. It is essential that no cavities occur in the
adaptor when filling. The membrane requires a pressing force of approx. 6
g/cm2to switch.
Gasket
"Full" sensor
"Empty" sensor
Mounting flange
Membrane surface
Avoid cavities forming
in the adaptor!
125mm
15mm

MBA100 User Manual, 2022-02, number 8011706, page 3/4 MBA Instruments GmbH
5. Electrical connection
The MBA 100 is a purely mechanical switch. Operation occurs without
any kind of electrical power supply. A changeover relay is actuated
via the membrane and this can switch an electrical signal.
The max. switching power of the relay is
- outside explosive zones: 250 V 16 A
- inside explosive zone: 250V V 10 A
Electrical contacts with unloaded membrane:
A cable with a round cross section and a diameter of 6 to 12 mm
must be used for the electrical connection.
After the connection of the electrics:
1. Tighten up cable fitting: 2.7 Nm
2. Place cover on and tighten cover screws: 3.5 Nm
6. Adjusting the switching point (e.g. after a repair)
The switching point of the MBA100 is already ideally set when delivered
and does not have to be readjusted. The adjustment of the switching point
should be first carried out when the MBA100 no longer switches in a
satisfactory manner e.g. if a new switch is installed during a repair.
The switching point can be readjusted with an adjusting screw in the head
of the device. The switching process must be observed at all times when
turning the adjusting screw. An appropriate measurement instrument
(continuity tester) can be connected to the "P" and "I" terminals to assist
with this. Calibration is carried out thus:
1. Load the membrane with approx. 1.5 kg
2. Turn the adjusting screw counter-clockwise until the (P-II) contacts
open.
3. Turn the adjusting screw clockwise until the (P-II) contacts close.
4. Turn the adjusting screw approx. half a turn further in the clockwise
direction.
7. Technical data
Bulk solids
Free-flowing bulk solids
Sensitivity
On: 950 g (6 g/cm2)
Off: (switching hysteresis): 350 g (2 g/cm2)
Option for heavy bulk solids:
On: 4600 g (30g/cm3)
Off: (switching hysteresis): 2800 g (16 g/cm2)
Temperature range (observe type plate)
MBA110: -20 ... 100°C
MBA120: -20 ... 200°C
MBA130: -20 ... 300°C
Housing
Die cast aluminium, 230D alloy (EN AC-44300) with higher
chemical resistance, IP 65 protection.
Dimensions (diameter / height)
203 mm / 120 mm
Membrane and flange
Stainless steel
Membrane diameter
174 mm
Flange size, hole circle
189 mm, 6 drilled holes 7 mm
(Special flange sizes see additional drawing)
Switch
Potential-free changeover, 250 V 16 A
Cable fitting
M20x1.5 second fastening optional
Weight
2 kg
Adjusting screw for
calibrating switching
point
II
I
P
II
I
P

MBA100
Document Information
Title: Operating instructions MBA 100
Issued: 2022-02
Product described
Product name: MBA100
Hardware: All versions
Manufacturer
MBA Instruments GmbH
Friedrich-List-Str. 7
25451 Quickborn
Telefon: [phone]
Telefax: +49 4106/123 88-89
E-Mail: [e-mail]
Information for warranty
Product properties and technical data listed do not constitute
any form of warranty definition.
© MBA Instruments GmbH. All rights reserved.
Subject to change