References EtherCat

Control of simulation control rooms in nuclear power plants, in communication with a simulation computer:
Acquisition and control of up to 35,000! Operating and display devices within 30 ms at the Krümmel nuclear power plant.
Another 10 control rooms in nuclear power plants in Japan and Switzerland in LON technology.

Simulation control rooms are 1: 1 replicas of the original control rooms of large power plants. Control desks with a length of up to 50 m, fully equipped with switching elements, signal lamps, monitors and instruments. However, these command and signaling devices are not controlled from the real area of ​​a nuclear power plant, but by a simulation computer. These are used to bring training programs to the simulation control room and to train and educate the operating staff, who can find the same working conditions and requirements as they can in reality when operating and monitoring the system. This is an important contribution to the safe operation of nuclear power plants.


In the project Krümmel was demanded, the number of 35000! Waiting devices with a sampling frequency of 32 Hz to capture. Specifically, this means that the delay time between input of a switching command and its feedback in each operating situation had to be below the human reaction and perception speed of 100ms. Another aggravating requirement was that the old 19 "card system should be easily replaced while retaining all the wiring and termination technology. Pin-compatible I / O components had to be developed to match the old system. The reason was no longer available spare parts of the original equipment manufacturer, a German electrical company.


The company UNITRO-Fleischmann was awarded the contract due to the good experiences of customers with their systems. Since 1998, more than ten full-scope simulation switchboards in Germany and abroad have been equipped with control electronics from UNITRO-Fleischmann.

These systems, which are primarily delivered to Japan, are implemented in LON bus technology. This allowed a sampling rate of 16 Hz to be achieved with approximately 20,000 control devices to be controlled. The requirement of 32 Hz at 35,000! Waiting devices could only be realized with an extremely fast bus system. For example, UNITRO-Fleischmann used real-time EtherCAT technology at 100Mbit / s for such a large and sensitive project for the first time.

The existing plug-in cards have now been replaced by the new plug-in cards developed in real-time EtherCat technology. The heart of these cards is a new ARM 7 processor with integrated SPI interface for communication with the SPI interfaces on the slaves on the backplane. The digital inputs received an input suppressor circuit for increased immunity to interference, while the outputs were designed for short-circuit protection. Mechanically, the cards on the input side had to be pin-compatible to the existing direct plug-in connection, while the bus-side connections had to be adapted to the new 19 "bus board. The new 19 "3U backpanel contains a BGA / ASIC EtherCAT slave controller for physical conversion of the Ethernet interface to an internal bus. 16 ESCs with integrated SPI are again located on the board for communication with the respective I/O plug-in cards.

System components are: EC mainboard 1/16 19 "rack, EC 16/16 plug-in card 16 dig I/O, EC 8/0 ana plug-in card 8 analogue inputs, EC 0/8 ana plug-in card 8 analogue outputs.

Overall, the cards were housed in 136 pieces of 19 "4U racks. Each rack also contains a 4U power supply and, in addition to the 16 3U card slots, a 1U jumper space for the connection cables. This design was dictated by the existing system, so that in the new installation only the racks had to be replaced, attached the system front connector and the back of the Ethernet bus had to be looped through 2 RJ 45 sockets to the master. The entire conversion of the plant could thus be carried out in a single week.