ABBCompact control system replaces PLCs Comfortable, more efficient integration of package units using AC 700F

simply in other systems.” This makes fault finding and maintenance substantially easie

Project: Converter for platinum extraction, 

Northam Platinum, Johannesburg, South Africa

Industry: Metal production

Northam Platinum Ltd. is based in Johannesburg, South Africa,

and mines and produces precious metals. Convertors are 

used to extract platinum from ore. These convertors are driven

using electrical motors. Until now, a PLC controlled the motors’

direct motor starters. This operating mode was not reliable 

and efficient enough for Northam, as the motors thus operate 

constantly at full output. That reduces the lifespan of the components and causes higher repair and maintenance costs to 

increase. 

When the application was modernized and converted to frequency converters to increase energy efficiency, the outdated 

PLCs were to be replaced. Customer requirements were a 

more compact controller, an improved presentation of alarms 

and results and an excellent cost/benefits ratio. 

Northam opted for the new AC 700F controller when replacing 

PLCs for the converters. Northam has been using the Freelance

800F system to control its smelting furnaces and other applications for many years and is convinced by the systems performance. 

One AC 700F controller now regulates one variable-speed 

drive. The motor output can be adjusted at any time to the 

current operating requirements of the application, as frequency

converters can be simply driven by the controller. The adjustment allows up to 50% of energy savings and processes can 

be better controlled. The increase in efficiency resulting from 

the intelligent speed control can be used in two ways: to increase productivity or to keep production stable while simultaneously reducing energy consumption. 

Integration of the AC 700F controller into the existing Freelance

800F system and the easy engineering with just one engineering tool, “Control Builder F” simplify commissioning and maintaining of the entire application. The configuration is particularly

simple as the visualization is also created with Control Builder 

F. Separate tools for programming the PLCs and to create 

operator images are no longer needed. Technicians now only 

need to handle a uniform engineering tool system wide. Production data and information such as signal descriptions, 

current and historical data, reports and detailed status information can be recorded over several years in the information 

management tool PGIM 800F.

As a result of its positive experience, Northam will modernize 

additional converters and other small plants using the AC 700F

controller in the near future. 

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Osby Parca produces high-performance boilers for hot water 

and steam. The product range spans from electric boilers with 

36 kW through to oil boilers with 16 MW. Osby Parca offers a 

wide variety of solutions: for solid fuels, steam, gas, oil, electricity and heat recycling, flue gas cleaning and biomass systems. These boilers are delivered to both small customers and 

key accounts - from sole proprietors for pipe installations to 

industrial customers and distance heating plants.

In order to control the fully-automated solid fuel boiler Osby 

PB2, Osby Parca has been using ABB’s compact Freelance 

800F control system for several years. This boiler, with output 

of 350 to 3000 kW is used to burn dry wood fuels such as 

pellets and briquettes. The control adjusts the combustion to 

the current load to ensure that there is a constant inlet temperature. Sensors and actuators regulate the draught in the 

firing plant, the movement of the grate and the fuel supply. 

Adjusting the draught in the firing plant controls the amount 

of air for the combustion process. This allows continuous 

control across the entire range of outputs. The combination 

of the boiler and the control system allowed Osby Parca to 

win several projects and it has equipped various power plants 

in Sweden. 

The Osby P500 model is a solid-fuel boiler for burning dry 

wooden fuels such as pellets, briquettes, peat and wood 

chips. The product range comprises four boilers with output 

of 100 - 1000 kW. In the past, Osby Parca used a PLC to 

control these boilers, as process control technology with 

comprehensive features was too expensive for the smaller 

models. In the majority of cases, the boilers were independent 

sub-sections of a total plant and as a result they were controlled as a “standalone solution”. That is why many users often

decided to use the lowest-priced hardware/software solution 

when selecting the automation systems to be used.

This clearly shows the advantages offered by the great scalability of the Freelance 800F system together with the new 

AC 700F controller. Osby Parca can now use the wide-ranging

advantages offered by Freelance 800F at a price similar to 

PLC + SCADA systems when controlling the smaller boilers. 

Compared to PLC + SCADA, a process control system offers