Power Plant Electrical Technologies (PPE), an ABB channel partner in South Africa, decided to use ABB’s new REX640 protection and control relay to develop a custom solution for Sappi’s Ngodwana pulp and paper mill. This solution will replace ageing relay panels with modern equipment, which offers additional functionality.
Sappi also wanted to upgrade the grid-tie protection system in accordance with South Africa’s public electricity utility Eskom’s grid compliance requirements. Since PPE enjoys a long-standing working relationship with Sappi and understood its client’s needs well, PPE was able to quickly diagnose the company’s problems. PPE’s knowledge and understanding of ABB’s power products enabled it to recommend the best solution to Sappi.
In order to meet Sappi’s requirements for a fully configurable and flexible protection relay, PPE together with support from the local ABB Distribution Automation (DA) team, proposed ABB’s new REX640 protection and control relay. The REX640 offers features, which ensure that the Sappi’s objective of having a highly reliable protection system for critical capital plant is met. The relay also meets the requirements set by Eskom, which was also one of Sappi’s objectives.
“The original installation included a number of individual protection and control devices with extensive wiring between them. Also, additional auxiliary relays were employed to realize the related control and interlocking logics. The upgrade to REX640 offered the possibility to combine all the distributed functionalities under one “roof”, substantially reducing wiring and need of external auxiliary relays, as well as simplifying connections towards the primary devices. The local human-machine interface of REX640 collects and visualizes all important system information to one location easily accessible by the operators,” says ABB DA Business Development Manager, Laurent Sowazi.
The product’s HMI includes an advanced 7-inch color touch screen with graphic display. This enables increased situational awareness and maximum usability. The HMI also includes ready-made application-based pages that minimize the need for graphical engineering, saving both time and effort. The LHMI pages can also be customized, if necessary, for optimum freedom.
PPE provided the full integration from development to engineering, installation and commissioning, with some software and application support from ABB.
Sappi, in turn, has heaped praise on the solution installed by PPE. “REX640 enabled us to offer an innovative and simplified hardware solution, which fully met Sappi’s requirements, especially the need for high-level reliability regarding the protection of critical capital plant and compliance with Eskom’s grid code,” says Cobus Van Zyl, Head of Maintenance for SAPPI.
According to Mitch McAllister, PPE’s managing director, Sappi is now considering upgrading all its transformer protection schemes with this state-of-the-art solution.
ABB’s REX640 is highly versatile and fully configurable protection relay. It can be used in any application requiring control and protection over embedded generators and complex power reticulation systems. The fully modular design allows unequalled customisation and modification flexibility, together with easy adaptation to changing protection requirements throughout the relay’s life cycle.
The REX640 protection and control relay can cover the full range of utility and industrial applications and manage multiple applications simultaneously, with the same device, guaranteeing flexible, versatile and cost-efficient protection solutions. This is asset management at its best.
About PPE
Power Plant Electrical Technologies is an Integrated Electrical Engineering Organisation, focused on supplying high technology systems and solutions to Mining operations, utilities and industry. Its management team are hands on and still practice their engineering skills in a consultative and advisory role to customers. In so doing, the company’s management remains in touch with core business matters and customers’ needs.
The company was founded in 1998 and has its head office in Nelspruit, Mpumalanga, South Africa, with a number of satellite and site offices throughout sub-Saharan Africa. Although PPE provides general electrical and instrumentation engineering and installation services, the company also offers a number of specialty services which are not commonly available. www.ppetech.co.za
About Sappi Ngodwana
Sappi Ngodwana is an integrated pulp and paper mill producing well over 2000 tonnes of pulp and paper products per day. The mill has 117 MW of imbedded electrical generation and is self-sufficient for its electricity demand. www.sappi.com/ngodwana-mill
