9
MBA200
·
Operating Instructions 8011417 V 2.2
·
© MBA Instruments GmbH Germany
Bin-level Indicator MBA200
4 First Start-up
4.1
Switching on
WARNUNG: Health risk / Explosion hazard
During operation, the unit head and the cable gland(s) must
be correctly closed and sealed. Otherwise the specified
type of protection and the specified explosion protection
(option) is not guaranteed.
4.2
Function test at first start-up
4.2.1
Check the operative function
After the first start-up, check the indicating function:
1. Allow the paddle to rotate freely: check the »empty«
indication.
2. Stop the paddle by hand: check the »full« indication.
4.2.2
Check for triggering by the bulk material
Procedure
While visually watching the bulk material level, fill and
empty the bulk materials container up to the MBA unit,
and check that the indicating function is correctly
triggered. This test should be made several times.
If the MBA unit does not correctly indicate the level
status:
Check the options for mechanical adaptation (see
below) and carry them out if necessary.
If the type of bulk material has been changed:
Do this test/adaptation again.
Possible ways of adapting the unit
●
Spring tension
(see figure):
– More sensitive setting (less tension), for light bulk
material: Bring the spring to closer position.
– Less sensitive setting (more tension), for heavy bulk
material: Bring the spring to a more distant position.
●
Paddle size:
– To make it more sensitive (for lighter bulk material):
Install a bigger paddle.
– To make it less sensitive: Install a smaller paddle.
●
Spring type:
If required, install a stronger or weaker
spring (3 different types available).
5 Maintenance
5.1
Recommended maintenance work
Clean the moving external parts:
Clean off deposits and
dirt on paddle and shaft, using a (soft) scraper and/or a
brush. Do not use force. Caution: Do not damage the
shaft sealing. Do not allow bristles to get between the
shaft and the shaft sealing.
Inspect the parts subject to wear
(highly recommended
in case of abrasive bulk material): Make a visual
inspection of the parts which protrude into the container
(shaft, paddle, etc.). Pay special attention to the
connecting parts (split-pins, etc.). Replace damaged or
dubious parts.
Clean the protective tube
(only if the unit is equipped
with an open protective tube): Clean the inside of the
protective tube to make sure that the shaft can always
freely rotate.
Clean the distance tube
(if existing
– if required for
explosion protection
page 7, § 3.3.4
): Remove dust
contamination from the distance tube.
5.2
Preventive function check
If the indicating function is seldom triggered during operation
(e.g. if the level indicator is used as a safety switch):
1. Inform the connected stations that a test will be carried
out.
2. Stop the paddle by hand / allow the paddle to rotate
freely, and check the correct status indication.
5.3
Safety information on opening
WARNUNG: Health risk / Explosion hazard
Before opening the unit head:
switch-off the power
supply and any connected signal voltage at an external
point. (Note: the level indication is thereby disabled.)
Only open the housing when you are absolutely sure
that there is no possible danger.
WARNUNG: High voltage inside the unit head (type 230)
In the type 230 unit head, there are always contacts with an
output of 230 and 115 V, even if the unit is powered with a
lower voltage (
page 9, § 3.4.6
).
Observe this information when operating the unit with
open unit head for service purposes. Take care. Give a
warning to other persons.
Severe dirtiness inside the unit head can affect the proper
functioning of the unit.
Protect the inside of the unit head from getting dirty.
5.4
Removing the unit head (repair note)
The unit head can easily be separated from the process
connection, without opening the process connection:
1. If the unit head is to be removed completely, disconnect
the electric cables first.
2. Loosen the fixing screw on the underside of the unit head
for approximately 3 mm (3
… 4 turns).
3. Carefully pull the unit head from the process connection
(along the direction of the shaft). This requires some
strength, due to adhesion and friction of the sealing: use
skilful power, but no brutal force; protect yourself against
tumbling and falling in the case that the unit head goes
suddenly free.
Re-assembly is made in reverse order.
