Modern Mining October 2020

COVER STORY

of a mobile substation the equipment is mounted in the substation at the Hamar Controls factory and most of the engineering and testing can be executed off-site in South Africa. “All the expensive resources can there- fore be applied here in South Africa and then just ship the entire tested facility to the mine site for connection and hot commissioning,” he says. With modern switchgear, there is a lot of setup work to do. On starters, variable speed drives and networks all pre-set work, program- ming and network testing can be done off-site if the mine opts for a mobile substation. If a control system is incorporated into the sub-

brick and mortar counterparts. Most mines in South Africa, says Joubert, still prefer the traditional brick and mortar solutions. However, it’s important to note that building an electric substation out of brick and mortar, he says, is probably the same cost as opting for the mobile substation, yet mobile solutions offer several benefits. The customer, says Joubert, can have the equip- ment built into the substation remotely, get it tested and commissioned and then shipped to site. “This is more beneficial for fast-tracked, time-sensitive proj- ects, because you can build the plant on the mine site in parallel with the electrical substation which is built off-site. When the site is ready for the substa- tion, you can just transport it to the mine and connect the cabling,” he says. The other advantage, adds Joubert, is that when working in remote places, especially mines in Africa, valuable site resources such as engineering and testing are often limited and expensive. With the use

station the complete system can be tested together with switchgear and controls before releasing the equipment to site. “On many of our projects in the past we have completed the control, network, starter and VSD setups at our factory in South Africa. These are expensive functions,” notes Joubert. To provide context, he adds, a VSD specialist easily charges between R2 000 and R2 500 an hour. “If you have to send a specialist to Guinea to do the setup, for example, you will have to pay them for up to two weeks, factoring in the travel difficul- ties, inductions and possible delays, while the actual work may take only a day or two. Here in South Africa we can have the specialist at our factory for a day or two, compared with several weeks into Africa. As most people involved with mining projects have experienced, the exact time of when commissioning will take place is not fixed and it is often difficult to book specialist resources at short notice. Except for

Hamar Controls’ newly-built mobile electric substation destined for Mozambique.

Key takeaways  With mines seeking to cut their costs at every opportunity, Hamar Controls’ mobile electric substations and control cabins offer a practical solution for remote mining proj- ects, pilot plants, fast-tracked projects and plants that may need relocation from time to time  The company offers two types of mobile substations, standard containerised and custom-built electrical enclosures  The standard containerised substations, come in 3 m, 6 m and 12 m sizes  Additionally, Hamar Controls supplies skid- mounted solutions for applications where substations or electromechanical plants need to be moved to new locations from time to time

Control cabin for a ship loader designed and manufactured by Hamar Controls.

12  MODERN MINING  October 2020