Remote Monitoring keeps gas flowing.
Credits: Abacus Automation | July 2016
Abacus was approached by a natural gas supplier, to provide a solution that allowed them to monitor remote end customer sites. Prior to the implementation of this solution, the customer would rely on telephonic information to decide how to co-ordinate gas delivery. Issues ranged from no feedback after working hours, to incorrect feedback due to human error. according to Dhiren Naidoo from Abacus Automation, their solution needed to accommodate the following fundamental requirements.
Providing multiple users situated at different points in the country the ability to simultaneously query the system for information.
Ensure strict end-user segregation, preventing other end-users viewing data that does not concern them.
To secure reliable transfer of data from end-user sites to the supplier.
The Automation System.
The SIEMENS SIMATIC automation components were chosen as the framework of the solution. While certain SIEMENS PLC’s can present process data using a built-in webserver, the development of multiple webpages for a complex process can be cumbersome and is limited in some aspects. SIEMENS SCADA products become the more robust solution to this by providing a web-based interface in parallel to a regular SCADA interface. This aids in development, cutting down on time spent as well as duplicate configuration. The solution also leverages the tried and trusted Internet Information Services built in to Windows to provide a reliable software framework for the web interface.
Being HTML5-based, the generated web pages also scale well between smartphones and PC’s. "SIEMENS SCADA also provides easy segregation of information and security management by authenticating users when presenting the webpage equivalents. This solved most of the data presentation requirements for our customer, meaning each of their end users did not require specialized hardware or software, embracing the “Bring Your Own Device” paradigm with minimum effort on our part as system integrators" Naidoo added.
A Robust Solution.
The remaining challenge was to gather data at more than one end-user site and display this information on the SIEMENS SCADA. SIEMENS communication protocols proved robust enough to work over routed networks and were therefore chosen to maintain regular data transmission from end-user sites to the customer’s main site.
The initial proposal for the solution placed the responsibility for the physical data links on the customer’s I.T. provider. While this was the ideal arrangement, complications later arose that allowed Abacus to provide a connectivity solution as well.
After the proper security precautions were taken, data links were set up between the customer’s premises and the end-user’s sites using popular, lightweight routing hardware via ADSL with 3G failover. It also provided access to the webserver at the customer premises, for those with the appropriate credentials. For security reasons, in this implementation, no control is allowed via the web interface despite the solution being perfectly capable of providing this functionality.
Mr. Naidoo concludes by saying: "Although Abacus rose perfectly to the challenge of providing a connectivity solution for the customer, it is recommended that the data link is handled by a company that provides connectivity as a service. This is beneficial to both the systems integrator and customer in that their data link is guaranteed to a measured metric, be it up-time or bandwidth"