Haverfordwest
central view
Votec, is a system integrator
and panel builder based in
Essex with over 40 years’
experience in controls
for water treatment and
Industrial effluent plant.
Votec’s latest project:
Votec designed, built and
commissioned the controls
for a new effluent treatment
facility for First Milk and
Cheese at the Haverford West
Creamery in Wales. The plant,
designed and built by C.A.P
Technology , Cheshire, treats
2,000 M3 of effluent each
day, ensuring that the outfall
meets stringent consent limits
suitable for discharge.
Votec based the control
system on the Allen-Bradley
CompactLogix PLC range
taking advantage of their
Integrated Architecture. A
single CompactLogix processor
controls the whole treatment
plant via an ethernet network
which is linked to local panels
at strategic points around
the site. This ensured that
site wiring was kept to a
minimum, an important
consideration given the size
of the plant, and enabled fully
comprehensive control and
monitoring facilities from the
main PLC in the control room.
Each of the local panels
carries Allen-Bradley point
I/O to collect local sensor
signals, the drive controls for
adjacent plant and an HMI to
provide operator control and
information.
Some of the panels contain
variable speed drives,
needed for a number of
pumps and blowers, with
sizes up to 160kW. These
drives are individually linked
and controlled from the
main PLC via the network.
All the VSDs are fitted with
Safe Torque Off, giving safe
stopping under emergency
stop conditions without the
use of expensive and spaceconsuming heavy contactors.
There are over 70
pneumatically operated valves
installed across the plant.
Valve islands are located in
cabinets at key positions
around the plant and are
directly linked to the network.
Bus addressing of the valves
reduces panel wiring and
helps to eliminate the errors
associated with hardwire
Haverfordwest
Air Blower & MBR
Manifold
MBR
Screenshot
connections. To simplify the
site installation, each valve
is brought out to a push-in
connector.
The system also includes a
remote monitoring facility
which has enabled CAP
Technology to optimise the
treatment process during
the initial period of operation
without frequent trips to site.
Votec has engineered
many effluent and water
treatment control systems,
based on a range of PLCs
including Siemens, Schneider,
Mitsubishi and Omron. We can
provide the optimum solution
to clients with the minimum of
hassle because we understand
these plants and have all the
in-house expertise to build
and program the systems.
Votec Ltd
16 Pembroke Business Centre
Gardiners Lane South
Basildon
Essex
SS14 3HY
Tel: 01268 521547
Email: [email protected]
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PECM Issue 18