OFFICINE OROBICHE S.p.A.
2/7
24010 Ponteranica (Bergamo) ITALY - via Serena, 10 - Tel. 0039/035/4530211 - Fax 0039/035/570546 - www.officineorobiche.it-e-mail:info@officineorobiche.it
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JULY ’14
Information subject to change without prior notice
IST/158-I
3. OPERATING PRINCIPLE
To the paddle(1), which is soaked in the fluid, through a rod, a
small piston (2) made from magnetic stainless steel is
connected; this small piston is housed in a pit (3) made from
non-magnetic material.
On the pit (3) a tripping device, which is drawn schematically
beside, is mounted. It is composed of a magnet (4) and a
miniature switch (5) that are connected to one another by
means of levers.
In low flow-rate conditions (fig.“A”), the magnet (4) is at rest,
whereas in high flow-rate conditions (fig.“B”), the magnet (4)
is attracted by the small piston (2) that causes the miniature
switch (5) to operate.
The difference between high and low flow-rate is called
”tripping differential”.
The arrow indicates the direction fo the flow.
4. INSTALLATION
4.1 INSTALLATION ON THE SYSTEM
Before installation, check the line connections for compatibility with the instrument connections.
The flow switch shall be installed in a perfectly upright position and the piping shall be straightaway for at least 5D
upstream and 3D downstream.
The flow switch body has an arrow indicating the direction
taken by the flow; comply with such indication at the assembling
stage.
Remove the adhesive tape that locks the paddle and the plastic
strip inserted in the tube, so that the stem becomes free to move.
Ensure that the entire paddle is inside the piping and that, at rest
(no fluid), it does not touch the bottom of the piping.
It is strictly prohibited to load the instrument with external loads
and it is the user’s duty to protect it from strain; do not use it as
resting point.
To avoid effects of galvanic corrosion, any use of materials
featuring a different electrochemical potential is prohibited. The
user shall adopt all those technical devices that can prevent this
event from occurring.
The system shall be equipped with the specified technical
device, to make up for overpressure going beyond the
maximum envisaged point.
For installation on piping exposed to strong vibration,
please contact the Customer service department.
4.2 WIRING
The flow switch has a terminal board inside the case for NC - C - NO connections (see
figure on the right).
Make sure that the cover of the housing is closed properly before powering up.
The user shall provide suitable ground connections that are such as to protect the staff and
any other equipment possibly present.
The NC-NO condition referred to herein is with null fluid.
NO =NORMALLY OPEN
C = COMMON
NC =NORMALLY CLOSED
