Problem Background:

In the south of Namibia are the well-known Aussenkehr wine farms, which are mostly owned by Cape Span South Africa. With large vineyard expansions annually, the client started struggling to withdraw enough water from the Orange River. During the peak summer months, 45 degrees Celsius can be seen as normal. High temperatures are ideal for producing good quality table grapes, but requires plenty of water at critical times. The client therefore had to look for a more reliable water solution as his pump station became very old. He was forced to build a new station, 5km from the offices on the river bank. This station had to be operational 24/7/365 and controllable from anywhere in the world.

Our Solution to the Problem:

BVI from Springbok was appointed as the consulting engineers and approached HmT to design and implement the control system. Our solution included the use of the latest automation technologies in SCADA, HMI and PLC with industrial wireless technology from Germany. A modular PLC controls the 4x 400kW VFDs via Modbus TCP/IP. There are 4x flow meters to monitor water flow and monthly usage. With large pumps like these, maximum demand control is crucial and was done with 3 phase power meters. With our sophisticated soft fill algorithms and pressure transducers we ensure there are no water hammering in the 5km pipeline to the reservoir. The entire system can be controlled in manual and then switched to automatic which allow for stop/start of pumps based on the reservoir level. Full motor and pump protections are built into the system as well as pump standby rotation.

With all the above mentioned features, this client now has the peace of mind that he gets the necessary local support from Cape Town to ensure his pumps are operational 24/7/365. He has now got control of his station anywhere in the world and in the event of quick fault finding, remote support is also available.