The Buffalo Pound Water Treatment Plant, constructed in 1950, provides safe, high quality drinking water to the cities of Regina, Moose Jaw and several smaller surrounding communities. The plant has undergone three major capacity and process improvements since its original construction and is presently among the most advanced water treatment facilities on the continent. The plant was one of the pioneers in the use of the GAC (granular activated carbon) filtration process for the removal of algae-produced taste and odor. The City of Regina used an average of 74.1 million liters of treated water each day in 2002.
The control systems used
to monitor and manage the filtration and delivery processes reflected the
incremental upgrades that occurred over the years. These systems were a
combination if PLCs, distributed control systems (DCS), and custom
electronics. As demand increased and reliability became paramount in
plant operation a decision was made to migrate to an integrated control
system. The requirements focused on three phases of operation,
commissioning, control, and maintenance. As this was a fully
operational facility the commissioning of the new hardware would need to be
fast and reliable in order to reduce downtime during transition. The
control of the system was required to interface with new and existing field
devices and control systems. A variety of input and output types were
required. The broad I/O offering found on ControlLogix met the requirements.
Maintenance at the facility was limited to periodic preventative measures.
This approach was not sufficient for a mainstream water facility so the
upgrade requirement focused on improving diagnostic, predictive and
preventative maintenance capabilities. A decision was made to
integrate a HART protocol device network into the PLC architecture allow
full access to device level data. This data was typically accessed
using a hand-held HART communicator resulting in long acquisition times.
The incorporation of Spectrum Controls Analog+HART I/O and CONNECTS communication gateway software allowed full access to HART-enabled field instrument data over the ControlLogix backplane. When combined with an device asset management software tool, system data could be monitored real-time allowing for more accurate predictive maintenance activity, real-time diagnostic capability, scheduling and substantially reduced downtime.
The result is an integrated control system with high performance data acquisition and diagnostic capability. The addition of HART I/O into the system has allowed full access to instrument level data which may be used to make better operation and maintenance decisions.
References:
Neil Anderson, Rockwell Automation - Area Manager
G.T (Grant) Gingara, Associated Engineering - Consulting Engineer
Westburne Electric, Curtis Tessmer - Authorized Allen-Bradley Distributor,
Saskatoon, Saskatchewan
Referenced Product:
1756sc-IF8H, 1756sc-OF8H - Analog+HART I/O Modules -
Datasheet
CONNECTS
- AssetWare to ControlLogix Communications Gateway Software -
Datasheet