|
NG-Data The Engiby's Data
Acquisition Concept |
Italic items are
available on request or need common agreement.
|
Concept |
The task of the NG-Data
concept is to collect data in a number of external sites and to send them to a
common Server. The data packages are self-described and spontaneously sent from
the sites to the server. The server is able to distribute and append the data
packages in various database tables (one per Value or Value array). New sites
as well as new data-points can be installed and will be dynamically added to
the server's database.
|
Data acquisition |
The data acquisition on
site can be realized in various ways:
Ø Local analogue inputs
Ø Any local PCD values
Ø Remote I/O modules
Ø Collection of values from external devices via a specific driver (on
request)
The data acquisition
feature includes a specific coding of the data including a unique
identification of the value, a timestamp, a status (Normal / Warning / Alarm)
and optionally calibration parameters. The acquisition is not limited to data
records for trend storage. The values can also be monitored with upper and
lower limits and an alarming feature can be activated. Also all relevant events
(Stop-Start of the PCD, Network problems, successful data delivery) are
generated and transmitted to the server.
The following buffers are
handled :
Ø Trend data
Ø
Alarming information
Ø Messages
Ø Process
values (on request)
Ø Frost data.
Reading of all values in one shot (on request)
Ø Event
information
|
Data package transmission |
The transmission of the
data package from the acquisition site to the Server is launched from the site
itself according to many possible condition like:
Ø
Specified time in the
day (or the night)
Ø Specified buffer
level
Ø
Any programmable signal
in the PCD
Ø
External command via
Web browser, Phone call, SMS command.
The recommended
transmission media is Ethernet or Intranet.
With some restrictions it can also be:
Ø Local manual reading
Ø
Direct serial
connection. Point-to-point or over S-Bus
Ø
Analogue/ISDN/GSM
Modems
Ø
SMS (alarm and small
number of data)
|
Server |
The Server is a Windows PC
running the Database Handler. The Database Handler is in charge of collecting
the packages and storing the various data in a database like:
Ø Access Database
Ø
Excel table (with some
restrictions)
Ø
Windows QL Server
(on request)
Ø Other SQL
or Supervisor Database(on request)
These data can be treated
by numerous customized applications like:
(Just as idea. Not included in the NG-Data package)
Ø MS-Office applications: Access,
EXCEL, Word.
Ø
Reported with Cristal
Reports
Ø
Published on a Web
site.
Ø
Imported into SCADA
system.
|
Alarming |
NG-Data alarms can be sent
over various output channels. The alarm type, defined by the originator is used
to select the output channel (SMS or E-Mail) and define the destination of the
message (phone number or E-Mail address).
Connection to SAGA
The SAGA solution is
a alarm management and engagement assistance software. The SAGA software
is designed to inform persons or groups of persons, in compliance with their
duty schedule and predefined scenarios.
The NG-Data package
includes a function to trigger Scenario in the SAGA software. A scenario can
launch several message amongst:
Ø
SMS
Ø
Pager
Ø
E-Mail
Ø
Fax
Ø
Phone call with voice
message
Optionally, messages can be
fully defined in the PCD and directly routed by the SAGA acting as 'Application
Service Provider'.
See the TECHWAN site for
more details.
|
Conclusion |
A reliable data acquisition
can be a difficult task to realized using basic SAIA-PCD functionality. Many
critical aspects must be identified, carefully analyzed and correctly solved.
Ø Time stamping
Ø Queuing and buffering
Ø Modem, ISDN or GSM communication
Ø Data transport reliability
Ø Data reception
Ø Site identification
Ø Data identification
Ø Data conversion
Ø Error reporting
Ø and so on, and so on…
With the NG-Data package,
all this points are part of the basic concept and integrated in an efficient
way.
|
Picture samples |
|
|
|
The Database
Handler is a Server program running under Windows and receiving the data
packages. An overview of the current activities is always available. The
'View DB' button offer a quick view of the recently stored data. |
|
|
The
Event table keep a track of all events occurring during the life of the
database. |
|
|
Each
data point is stored in a table including one or several values in a defined
format with timestamps and status (Normal, Warning, Alarm). |
|
|
The Site
program running in the PCD is configured to monitor the buffers and call the
Server according to several conditions like: Alarm detected, buffer full or
predefined time reached. |
|
|
Example
of full configuration of trend data to record and High/Low Warning levels and
High/Low Alarm levels. |
|
|
Back to Engiby main page Engiby / 06.06.2005 |
