City
of Philadelphia
Data & Design
Systems has developed various packages involving embedded systems,
and Windows interfaces, including a PLC interface for the City
of Philadelphia's water department. The system was designed to
replace a Wonderware Factory Link application.
The
system monitors and controls the flow of waste water. Consisting of
a Windows NT 4 server utilizing raid level 5 running on SQL Server
7.0, a data collection computer with a digi-board which interfaces
with 16 modems is used to call the PLCs located at approximately 260
sites throughout the city of Philadelphia. The computer calls
the sites, triggering the sites to call in alarms in real time.
A Data Concentrator server was written in VC++ and calls the Modicon
PLCs using a bank of 16 modems. This multithreaded application uses
a Modbus protocol, collects all the information and stores it in the
SQL server database. The information is then used for trending,
reporting and alarms.
The
HMI interface is written in VC++, and replaces an older Factory Link
application. Visual C++, Visual Basic and Crystal Reports were
used, with Access and SQL Server as the databases. Sockets
were used to develop the real time portion of the system, which
transmits the information to the client computers. Prototypes were
developed to demonstrate how to upgrade the present system using
Microsoft Net technologies as well as a Pocket PC interface.
Examples:
MMI
Reports
Data
Collection System
