P-NET in General

P-NET is used in thousands of installations all over the world. Choose from the list below to see descriptions of some typical applications:

Concrete Industry

Haarup Maskinfabrik A/S in Denmark manufacturers machinery, equipment and complete plants for the concrete industry.
Concrete is mixed using read in recipes, consisting of sand, cement, water and different additives.
Haarup Maskinfabrik A/S designs the automated plants and as well as well as assembling and final installation.
The plants are not programmed individually, but the very often complex, pipe and machine diagram is loaded into a general purpose concrete program.
The ingredients are automatically weighed out from a number of silos, e.g. to a hoist, which is filled from a weighing belt.
When the hoist is filled, it is transported to the top of the mixer.
The hoist is unloaded and water is added at the same time.

P-NET is used for the control and supervision of the many conveyor belts, mixers, valves, pumps, load cells and flowmeters incorporated within the plants.
A number of communication units are connected to the P-NET. These units are distributed throughout the entire plant, and are used for ordering.
A P-NET controller controls the entire plant, as well as automatic data transfer of administrative data for PC’s.
The motor starters are installed in a centralised panel.
Load cells are connected to weight transmitters. All control modules, including weight and flowmeter transmitters, have built-in P-NET interfaces.
The concrete is internally handled by means of conveyors, to a tiling machine. The tiles are automatically palletised.
More than 80 complete plants have been produced using P-NET. Haarup Maskinfabrik A/S delivers most of their plants throughout Europe. The first plant was installed in 1984.

Scope of P-NET installation

100 Digital Input/Output 
2 Analog Input (Pt100, 4-20mA) 
1 Controller with data screen 
2 Magnetic inductive flowmeters 
8 Communication units
10 Weight transmitters 
800 meters of P-NET cable 

More than 80 systems installed with following specification: 
50 – 300 Digital Input/Output 
0 – 12 Analog Input (Pt100, 4-20mA) 
1 – 4 Controllers with data screen 
1 – 8 Magnetic inductive flowmeters 
1 – 30 Communication units 
3 – 20 Weight transmitters 
100 – 1000 meters of P-NET cable

Textile Production Plant

Yarn breakage is monitored on all bobbins. Production efficiency is also recorded. All data collection is performed by means of P-NET.
The factory utilises P-NET compatible equipment for the control and supervision of the large number of machines and systems.
The yarns are used to make clothing, upholstery fabrics, original seat covers for cars, and for other technical applications.
Different texturising methods are used, such as air-texturising and friction texturising.
The textured yarn is heat treated in autoclaves.

Each autoclave has its own controller, which operates on its own local P-NET, and all the autoclaves are interconnected within a larger P-NET.
A waste heat recovery system is installed in the basement. This system is also controlled via P-NET.
A number of PC’s collect data from the P-NETs throughout the entire factory.
These data are send to an IBM administrative system via an IBM Token-Ring, which can then be processed and displayed on any PC on the network.
The factory has its own department for designing, installing and programming the automatic systems.
The first P-NET was installed in 1988 and every year, the plant has been extended.

Scope of P-NET installation

4000 Digital Input/Output
200 Analog Input (Pt100, 4-20mA) 
30 Controllers with 68000 CPU 
4000 meters of P-NET cable

Animal Feeding & Climatic Control

This P-NET application was recorded at a pig farm near Hobro in Jutland, Denmark.
Skiold Datamix A/S, in Denmark, manufacturers and installs advanced, fully automatic pig-feeding plants, called MultiFeeder.
Skiold Datamix designs the plants and associated automation, as well as assembling and installing the systems.
The plants are not programmed individually, but a “pipe-diagram” is loaded into a general purpose feeding program.
A number of weighing and mixing tanks, feeding tanks, raw material silos and storage tanks can be controlled by the system.
The composition and amount of feed for the individual pig sties is adjusted automatically using information about the size and type of pigs.
Only 3 people are needed to run the entire farm.
Mixing is performed automatically. The feed for the pigs is distributed via pumps, flowmeters and valves.

The MultiFeeder is provided with a newly developed pipe mouse system, which separates water and feed within the pipes. Therefore the pipes are always left full of water.
P-NET is used for controlling and supervising the many valves, pumps, weigh scales and flowmeters within the plants.
More than 130 complete plants have been installed, and approximately 150 plants are expected to be ordered each year.
Datamix delivers most of the plants within Europe.
The system utilises a built in sow management system, for up to 1000 sows.
With certain valves, a sensor informs the computer that feed is needed.
The system also provides automatic data transfer of administrative data for PC’s.
The size of each plant varies, depending on the size of the farm.
The first plant was installed in 1990.

Scope of P-NET installation

400 Feeding valves
4000 pigs
20 Silos for raw material
1 Controller with 68000 CPU
1 Hand held dataterminal
4 mixers
3 Magnetic inductive flowmeters
4 Weight transmitters for loadcells
1400 meters of feeding pipes

More than 130 “MultiFeeder” installed with following specification:
50 – 1000 Feeding valves
1 – 40 Silos for raw material
1 Controller with 68000 CPU
1 Hand held dataterminal
1 – 4 PC, operator terminal
1 – 8 Mixers
1 – 8 Magnetic inductive flowmeters
1 – 8 Weight transmitters for loadcells

Fuel Management

British Rail has built a new commuter train servicing depot at Aylesbury in the U.K. This project is a Fuel Monitoring and Inventory Management System and is the first of a number of sites currently being planned by British Rail.
The system meters fuel oil (diesel) to power the trains, lubrication oil for the vehicle engines, and glycol for engine coolant, as antifreeze. 
The fuelling of a train is monitored and recorded. The operator is prompted for a train identity, before fuelling can commence.

The installation is scattered over a wide area and has 21 sub-networks and a primary network. 24 controllers are used for monitoring, controlling and as operator interfaces. 
Tank levels are measured for a stock management system. Temperature measurements are included, to compensate for expansion. 

Numerous turbine flow meters are connected to P-NET interface modules. Within these modules, linearising and temperature compensation of flow signals are performed. 
The automation system was designed and configured by FMA (Flow Measurement and Automation) Ltd., in Berkshire, England. 
The plant is equipped with a colour graphics system, also connected via P-NET. This graphic control system is used for supervisory control, tank management and report generation.

Scope of P-NET installation

45 Digital Input/Output
16 Analog Input (Pt100, 4-20mA) 
24 Controllers with 68000 CPU 
24 Intelligent flowmeters 
21 Sub networks, 1 primary 
1 Colour graphic system 
1500 meters of P-NET cable

Fiscal Metering on Oil Distribution Truck

The Ultrakust Electronic Company in Germany, produces data acquisition and control equipment for oil trucks.
The modular systems on oil trucks provide a number of benefits to the truck operator. The system includes control of pumps and valves, and logs all the measured values.
The pump is activated via a small control panel. The entire system is based on P-NET. More than 500 systems have been installed on trucks in Germany, and more than 120 systems are expected to be installed each month.

Various mineral oil products are delivered to both petrol stations and smaller garages, as well as private individuals.
The delivery quantity is continuously measured by means of a calibrated mechanical flowmeter. The actual temperature continuously compensates the measured volume. The system is approved by the German authorities, PTB.
Having all the measured values available in an on board computer, the data can be used to print invoices immediately.
A machine readable giro deposit slip is also printed out. All the data are logged, which can then be used by administrative systems.

Scope of P-NET installation

More than 500 systems installed with following specification: 

2 Controller with keyboard/display. 
1 Printer for invoices/delivery. 
1 Temperature sensor. 
1 Mechanical flowmeter. 
1 – 24 Digital Input/Output. 
Automatic logbook. 
Interface to other equipment.

Fully Automated Ferry in Holland

This ship runs between the island of Texel and Den Helder in Holland. 
The ship is called “M/S SCHULPENGAT”, and it is owned by TESO, Texel Eigen Stroomboot Onderneming. The ferry was build in 1990 at Verolme Shipyard Heusden. The automation system is designed and programmed by IPH in Denmark. The automation is performed by means of P-NET modules. 

Having a length of 110.4 m, a width of 18.7 m, and a designed draft of 3.8 m, the ferry has a capacity of 1320 passengers and 245 cars.  The actual crossing only takes 20 minutes. 

The entire system is grouped into 19 sub-systems, each dealing with their own specific functions on the ferry.  Two redundant graphical PC supervision systems, each having its own PC network, are connected to the P-NET. The IPH system includes a number of subordinate data acquisition and control systems, based on the IPH Marine Automation System, MAS. These systems are interconnected via two double redundant local P-NET networks.

The ship uses a diesel electrical principle, with six diesel generators sets for the propellers. Each of the six engines are controlled, and incorporates an engine safety system.
The 4 electric propellers operate using 3000 volt, 720 Amp. 

The generator connection system and circuit breakers are controlled in two separate switchboard rooms. 
The ferry and equipment is classed by Lloyds Register of Shipping. 

More than 50 complete ship systems are installed world wide by IPH.

Scope of P-NET installation

1020 Digital Input/Output
480 Analog Input (Pt100, 4-20mA) 
23 Controllers with 68000 CPU. 
2 Redundant P-NET networks. 
19 Sub-systems. 
2 PC graphic systems, 
14 PC’s 
700 meters of P-NET cable.

Cheese Production Plant Control System

MD Food at Rødkærsbro in Denmark is a dairy, which produces cheese. The dairy is among the largest cheese plants in the world. The cheese products are Feta and Mozarella. The dairy is spread over 9,600m2 and has 140 employees. Each day, approximately 800,000 litres of whole milk are received and processed for skim milk, cream and cheese milk. 

The entire automation of the dairy has been carried out by means of control and supervision systems using P-NET. The automation system has been designed and programmed by SattControl A/S, in Silkeborg, Denmark. 

The dairy is split up into a milk reception section, a milk processing section and a cheese processing section. Each section works as independent unit, and are linked together by means of P-NET.  The storage tanks in the milk reception section hold 300,000 litres each. The milk processing room is equipped with 15 controllers, which are used for monitoring, controlling and as an operator interface. 
The operators can select different recipes and various treating lines for pasteurising and homogenising the milk.

50 magnetic inductive flowmeters are installed at the dairy. All the flowmeters are equipped with a P-NET interface. 
The system is very decentralised, and the controllers and I/0 modules are located near the sensors, valves and other control equipment. 
The motor starters are grouped into a few, but very large panels. 

The first P-NET section was installed in 1989, and nearly every year since then, the plant has been extended. 

The P-NET cable is installed with the power and signal cables. The signals for motor starters and feedback signal are then connected directly to P-NET interface modules. 

The plant has been extended to include a data acquisition system and a service/maintenance system, which are also connected via P-NET. Production runs continuously, 24 hours a day.

Scope of P-NET installation

2300 Digital Input/Output
130 Analog Input (Pt100, 4-20mA) 
40 Controllers with 68000 CPU. 
50 Magnetic inductive flowmeters. 
27 Weight transmitters for loadcells. 
10.000 meters of P-NET cable.

Milk Truck Data Collection System

The Ultrakust Electronic Company in Germany, manufactures P-NET systems for milk trucks. Each day, milk is collected from several farmers. The system measures the volume, average temperature and pH value of the milk. It also provides automatic control of pumps, valves and other equipment on the truck. All the measured values are logged. 
In addition, very small amounts, approx. 20 litres, are collected. The supplier number is automatically read in via a magnetic reader, and is stored with the collection data.

The entire system is based on P-NET. Currently, more than 1000 milk truck systems from Ultrakust are installed worldwide. 
A system typically contains 3 or 4 P-NET slave devices, connected to the system master, which contains the main software. The amount collected is measured by means of a magnetic inductive flowmeter having a P-NET interface. The entire system is approved by the German authorities, PTB. 

An automatic sampler device continuously takes samples from the collected milk, for later lab tests. The samples are taken by a peristaltic pump, having a stepper motor, which is controlled by P-NET. A barcode on each sample bottle, ensures that the correct association of samples and data can be made later, at the lab. 

When the milk is unloaded at the dairy, the driver removes the data cassette, and all the collected data are transferred to the dairy computer system. For the sample bottles, another solid state memory is delivered holding the sampler data for the lab.

Scope of P-NET installation

More than 1000 systems installed with following specification:

1 Controller with keyboard/display. 
1 – 2 Printer for tickets, lab results. 
1 – 2 Temperature sensor. 
1 – 2 pH sensor. 
1 – 2 Magnetic inductive flowmeter. 
1 – 24 Digital Input/Output. 
1 Magnetic reader Interface to other equipment.

Factory Environmental Control

The Ultrakust Electronic Company, is located in Bavaria in Germany, and has more than 200 employees. Ultrakust has recently build a new 8,000 m2 factory building. The entire automatic control of the building automation is realised by means of P-NET modules. The system consists of about 2500 data points, for the control of lights, sunshades, heating valves, air condition and hot water. Personnel entry control is performed by means of window observation, motion detection in rooms and electronic door locks. 

The design and installation of the entire automation system has been performed by Ultrakust.
Local panels are found in every room. More than 250 slave units are connected to the network. 
The heating system is also controlled via P-NET, and compensates in accordance with meteorological conditions. 
The system is implemented using 7 local P-NETs, formed as 7 independent cells in “outer” rings. These “outer” rings are connected to another P-NET ring, an “inner” ring, which is used for communication between the cells. 
One ring deals with the mechanical production area.

Another ring deals with the electronic production area. A graphic control system based on P-NET is connected to the “inner” ring. 
Each ring is an independent cell, and slave modules are connected to their local cell. 
The ventilation systems are found in the basement, and the control of these systems are allied to the heating systems. 

The system is also connected directly to a PC and a Novell-Network. A database is connected to the PC network and information is down loaded to the controlling units, e.g. air exchange and temperature settings. This information can be retrieved from anywhere on the network. 

The P-NET interface modules for controlling the ventilation systems are installed in a number of panels. 

Slave modules produced by different vendors operate on the same network. Energy production and distribution is controlled and optimised using the P-NET control system.  To optimise energy costs, the current load is monitored and the maximum power is controlled. 

The P-NET control system has saved on installation costs, reduced operating expenses and made it possible to include all the technical installations in one network.

Scope of P-NET installation

2500 Digital Input/Output
108 Analog Input (Pt100, 4-20mA) 
6 Controllers with 68000 CPU. 
2 Magnetic inductive flowmeters. 
15 Converter RS232 – P-NET 
1 Colour graphic system 
2000 meters of P-NET cable

Test Line at Bosch-Siemens Machine Factory 

osch-Siemens at Dillingen in Germany is the biggest and most modern dish washing machine factory in Europe. The factory has more than 2500 employees.
Approximately 6,500 machines are produced each day. The machines are marketed as several different makes. Each machine passes a severe quality control test. A total of 8 test lines each with 35 testing stands is used. 3 of these testing lines are now controlled by P-NET equipment.
The machines change position every 40 seconds throughout the testing line, and are then removed at the starting point.
The mounting and testing of the machines is performed in a continuous flow.
Each machine is connected to water, drain, power and test equipment.
The test is a combination of a visual inspection and an automatic function and performance test.
The design and installation of the entire automatic testing system was performed by Ultrakust.

Each testing stand has its own measuring station, which performs the testing, measuring and data logging. The identity of each machine is read by means of a barcode reader, and stored with the test results.
The P-NET module which performs the testing is equipped with a graphic data screen. The test results can be seen on the screen as function of time.
Errors during testing are diagnosed and displayed.
P-NET controllers are used as gateways, and for managing the P-NET interconnections.
The P-NET communication is performed via infrared transceivers.
PC’s collect data for test reports and for quality management.
The assembly and the internal handling of the machines is computer controlled, and the trucks, which deliver the raw materials, are routed via a radio link.

Scope of P-NET installation

97 Measuring sections 
169 Digital Input/Output
390 Analog Input (Pt100, 4-20mA)
97 P-NET modules with CRTs 
4 PC’s with P-NET interface 
19 Bar code readers
21 Infrared P-NET tranceivers
800 meters of P-NET cable

The Intelligent Building

In this project P-NET has been utilised in areas such as control, regulation and supervision of all the installed electrical, mechanical and climatic control equipment. Furthermore, P-NET is an integrated part of the Company’s PC network, such that telephone, fax, and other electrical equipment, combined with fire and security alarm processes, to become a consolidated automated building solution. In addition, a number of PC software utilities provide the ability for any building control to be accessible from any of the work stations on the network.

Scope of P-NET installation

2500 Digital Input/Output
108 Analog Input (Pt100, 4-20mA) 
6 Controllers with 68000 CPU. 
2 Magnetic inductive flowmeters. 
15 Converter RS232 – P-NET 
1 Colour graphic system 
2000 meters of P-NET cable