WORLD OF INDUSTRIES 02/2018

Powering Africa using IO-Link
As an enabler of high-performance Industry 4.0
concepts IO-Link has become indispensable in tool
machine engineering and in production facilities. But
hydro power plants as well can be wired quickly and
efficiently using IO-Link. At the Mount Coffee dam in
Liberia an intelligent IO-Link installation connects
dozens of sensors and actuators over long distances.
In December 2016, after more than 20 years of interruption the
first turbine was started up, and now all four turbines are feeding
22 megawatts each into the power grid. The origins of the Mount
Coffee dam, which lies 30 kilometers northeast of the Liberian
capital Monrovia, go far back: the former dam was finished in
1966, but was almost totally destroyed during the Liberian civil
„Getting a hydroelectric power plant online
quicker using intelligent cabling technology“
Author: Wolfgang Zosel,
Journalist, Reutlingen, Germany
war from 1989 to 2003. When in June 2014 the Liberia Electricity
Corporation (LEC) contracted an international consortium of
companies to rebuild the dam, extensive parts of the plant had
literally turned to grass.
Together with other companies, like Balluff, the Austrian firm
Andritz Hydro was contracted to rebuild the power plant on the
Saint Paul River. Andritz Hydro is one of the largest companies
in the market for hydraulic power generation. The responsibilities
included the complete hydraulic steel structures consisting
of all the electronics, drive technology and control systems. The
company refurbished both the ten radial gates on the dam and the
four intake gates for the turbines. The radial gates are used to control
the water level on the upstream face of the reservoir and are
driven by cable winches. The intake gates bring the water to the
turbines and block the inflow (shut-off valve) when a fault occurs
such as a break in a pressure line. The drive is hydraulic.
This includes electric and hydraulic drive units as well
as various supporting systems. Balluff assisted in the
development of integrated wiring systems.
AUTOMATION