As well as the one or two alarms initially considered, Sasol thought of going further. Maintenance electrician Johan Oosthuizen suggested that motors, auxiliary equipment, panels, and alarms should have monitors, providing wider visibility of the plant. Having previously used its equipment in Sasol’ s Analysers department, Oosthuizen’ s colleagues directed him towards Omniflex, recognising the similar function required in remote monitoring all panels’ operating status, and to actively seek out any faults or failures.
After contacting Omniflex at the end of 2018, Oosthuizen outlined the parameters of the project.
“ As well as the alarms we wanted to look at voltage, current, analogue signals, and trip status of auxiliary systems. These are all important operating conditions of electrical panels,” explained Oosthuizen.
The proposed solution
Sasol was looking for something simple to implement with proven reliability at a manageable cost. Following previous work with Omniflex, it felt confident in its decision to work with the remote monitoring expert on this project.
While Sasol handled system design and human machine interface work in-house, Omniflex provided consultancy on network architecture, hardware and the equipment that would be required. Sasol wanted a hardware solution that enabled it to monitor the status of each substation reliably. The distances between substations and the control room involved
approximately 1 km of cabling. This could easily be covered by Omniflex’ s CONET protocol, which can bring field data back to a control room or supervisor’ s office in a cost-effective way, covering distances of up to 10 km.
Omniflex supplied its Maxiflex modular rack system – a process automation controller – which allows the user to choose their I / O and bring in the data. Approximately, 64 analogue inputs and 96 Digital Inputs are required for each network node. Maxiflex nodes can support 15 I / O modules which can accommodate up 960 points for monitoring. After it’ s plugged into the system, it automatically registers the presence of modules and processes their data into the Omniflex Data Interchange table for the Conet Network to access.
“ We’ d already proven the reliability of our Maxiflex systems in other departments at Sasol, so they knew they were getting trusted technology,” explained Ian Loudon, head of international sales and marketing at Omniflex.“ The scale of the project – with over 130 panels and thousands of data points – was ideal for our architecture. With CONET and Maxiflex, distance and volume were not a problem.”
Results
With a new system in operation, Sasol’ s plants no longer required manual inspections. Previously, 48 field controllers had to check everything every morning, whereas one person can observe remotely
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