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

The AC 700F controller increases the scalability of the 

compact control system Freelance 800F towards very 

small applications with only a few I/Os and closes the 

gap between PLCs (programmable logic controllers) 

and complex process control systems. It is suitable 

for smallest applications with about 10 to 250 I/Os per 

controller and thus opens up additional application areas 

for the Freelance 800F control system, which is suitable 

for both small and also medium-sized projects with several thousand signals. Comfortable, advanced functions 

of control systems are now also available for very small 

applications – and all at a very reasonable price. The 

AC 700F controller offers a large number of advantages 

compared to a standard PLC with visualization from thirdparty vendors. The projects on the following pages show 

these advantages and the various application areas for 

the AC 700F controller. 

Thanks to the compact control system Freelance 800F and its 

AC 700F controller it is now possible for smaller automation 

solutions, which to date have been dominated by PLCs, to 

benefit from the advantages of process control systems, 

particularly in the process industry. There is a wide range of 

use in many industries including chemicals, petrochemicals, 

oil and gas, metals, cement production, glass production, etc.

The AC 700F controller can be integrated into existing Freelance

800F systems in the same way as the AC 800F controller. 

In contrast to PLCs, the AC 700F controller offers all of the 

advantages of the compact control system. Important for 

engineering and maintenance: A single engineering tool for 

all tasks: Control Builder F. 

DigiVis, the visualization tool, makes operation easy, structured

and intuitive. Pre-engineered components such as faceplates, 

module diagnostics, event lists, the alarm line, trend displays 

and automatically generated SFC (Sequential Function Chart) 

displays play a key role in this regard. The use of predefined, 

field proven libraries including faceplates significantly eases 

the transparency, readability and adaptability of the application

and substantially increases security. The advanced diagnostic 

options and improved alarm handling allows cost cutting in 

the operation and maintenance phase and asset availability 

can be enhanced. This substantially increases the economic 

efficiency of the entire plant. 

AlzChem GmbH in Trostberg, a subsidiary of Evonik Industries 

AG, produces specialty chemicals products with a wide range 

of uses. These chemicals are used, for example, in the production of crop protection products, pigments, dyes, pharmaceuticals and polymers. 

In the past, an inverted filter centrifuge in a system for extracting natural substances was PLC-controlled at AlzChem GmbH.

The program code for the PLC, a standard program from the 

manufacturer, was not transparent and needed specialists to 

make changes. The program was not intuitive and diagnostic 

analyses were only available to a very limited extent. In order 

to simplify programming and to optimize the process control, 

AlzChem thus decided to use the AC 700F controller. This replaced the PLC and was integrated into the existing Freelance 

800F system without any problems. 

This offers several advantages for AlzChem: The use of one 

single engineering tool to configure the entire system simplifies

engineering and saves a significant amount of time during 

commissioning. After transferring the program the system is 

easy to understand and maintenance is simpler.

During the operating and maintenance phase, the wide range 

of diagnostic options (sequence control-, hardware -, interlock 

diagnostics), the intuitive graphical user interface and mature 

alarm and report management allow costs to be cut. This 

reduces downtime of the application and cuts maintenance 

Project: System for extracting natural substances, 

AlzChem GmbH, Trostberg, Germany 

Industry: Chemicals

expenditures. All this improves the efficiency of the entire 

system and the slightly higher acquisition costs compared to 

a PLC amortize within a very short time.

Hartmut Rohner, Head of Electrical Systems, Instrumentation 

and Control at AlzChem, is particularly impressed by the simple

and clear handling of the AC 700F controller and the Freelance

800F system. “It is easy for anyone to learn how to operate 

the software and hardware. In contrast, it was practically impossible to understand the standard program supplied by the 

manufacturer together with the centrifuge.” Mr. Rohner also 

sees clear advantages over other systems when it comes to 

maintenance and faultfinding. Whereas with other manufacturers faultfinding is only possible using a handheld device in 

the field, Freelance 800F provides extensive analysis options 

right in the control room. “Now I look at the status and can 

see straight away where the error is. That is not possible that 

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 

more functionality, for example automatically generated diagnostic information and alarms as well as easy and fast online 

optimizations of applications.

In addition, simplified remote diagnostics in central control 

rooms is possible, as the control technology automatically 

generates system alarms and system diagnostics, which are 

available using PC technology. 

Osby Parca is very pleased: “The AC 700F Controller combines

the functionality of a control system with the price level of a 

PLC with a visualization solution. The uniform tool for configuring the controller and the operator station with automatically 

generated faceplates (operator windows) saves time for engineering and commissioning. Time can also be saved in ongoing

operation and for maintaining the application thanks to advanced

diagnostics opportunities and improved alarm handling. This 

cuts installation costs and significantly increases the plant’s 

economic efficiency.” 

Osby Parca is convinced of the opportunities offered by the 

Freelance 800F control system and in future it will fit even 

more boilers with AC 700F and AC 800F controllers. 

Project: Pneumatic conveyor system 

for aluminum oxide powder, Sasol, Brunsbüttel, Germany

Industry: Chemicals

At Sasol in Brünsbüttel the AC 700F controller has been installed to control a pneumatic conveyor system for aluminum 

oxide powder. This system was controlled using a PLC in the 

past. Sasol is a convinced, long-standing user of the compact 

control system Freelance 800Fand thus decided to use the 

AC 700F Controller when replacing the PLCs. Customer requirements were the transfer of the existing application into 

the new controller, the subsequent optimization of process 

control through the use of diagnostic features and short setup 

and installation times. 

In addition, the system was to be configured by one of the 

customer’s application engineers, who had never worked with 

the Freelance 800F system before. After a short training period

and with ABB’s support during the start-up phase, it was possible to successfully put the project in operation in the shortest

timeframe. The easy-to-learn and intuitive configuration of 

Freelance 800F was the crucial factor for Sasol when they 

chose the control system. 

Thanks to the compact footprint of the AC 700F controller, 

the old PLC control could be exchanged without having to 

modify the control cabinets - even the existing wiring in the 

control cabinet remained unchanged. This allowed considerable advantages to be gained in respect of operation and fault 

diagnostics but with minimal outlay. The main advantages of the

compact Freelance 800F system compared to a PLC solution 

are the simple configuration, operating the plant from the 

control room and the possibility of remote access for maintenance work. 

A touch screen operator station replaces the switches and 

lights at the control cabinet formerly used as operation elements. This makes it easier for plant operators to control the 

equipment locally and also allows all of the other systems 

connected to the process control system to be used. 

At Sasol, other outdated control cabinets are to be modernized

with the new AC 700F controller in the near future