Background Information The European tunnel system connecting Great Britain and continental Europe was one of the great engineering miracles of the late 20th century. The tunnel was opened in mid-1994 and is the result of many years of cooperation between the British and French partners and the international group of engineering companies and suppliers.

AuCom Electronics is one of the few companies that has been selected to provide control systems during the construction process and after the completion of the tunnel project.

The problem The European Tunnel consists of two railway tunnels, each of which is 50 kilometers long, plus a maintenance tunnel that runs through two railway tunnels. The system uses the pump to drain water from the tunnel. Since more than 200 trains pass through the tunnel in each direction every day, it is extremely high that the pumping system can provide continuous smooth operation and long-term reliability.

In the early stages of developing the tunnel plan, engineers identified factors that could affect the pumping system. These factors include voltage interference, card pumping, and liquid hammer action when the pump is stopped.

Solution engineers identified a high-quality solution to control all pumping processes during the excavation process. During the international tendering process, AuCom finally bid successfully and won the supply contract for the electronic soft starter; these facilities will be used to control several 700-volt, 310-kilowatt drainage submersible pumps in tunnel excavation.

Due to the following three main reasons, AuCom was selected as a supplier in this project:

experience. AuCom has many years of experience in the field of electronic soft start and has an industry-recognized reputation for reliability and engineering quality in the pumping industry.
Product Series. AuCom offers multi-type, multi-purpose solutions. AuCom's low-voltage solutions can be used for supply voltages up to 1000 V, 50 Hz or 60 Hz and are suitable for use with motors from 1 hp to 2000 hp.
service. AuCom offers absolute first-rate customer service. The company has offices throughout the world and provides full on-site support during tunnel construction.
The benefits of soft start provide important operational advantages in the tunnel environment.

Reduced current level

Electronic soft start reduces the current level during starting. The closed-loop electronic soft starter ensures that the motor is started with the minimum possible starting current required for the particular application, thereby reducing voltage disturbances for weak or limited power supplies.

Card pump

Soft starters prevent equipment damage when the pump stalls or pumps. AuCom's electronic soft starters ensure that the device is safely shut down so that stall pumps and motors are not affected by damaging electrical or mechanical stress due to full voltage.

Liquid hammer

When suddenly stopping the pump, the equipment may be damaged by water hammer or liquid hammer. The AuCom soft starter provides a soft parking facility that reduces the voltage applied to the motor, enabling gentle pump and liquid speed reductions, further reducing equipment damage.

Protective function

The AuCom soft starter provides an auxiliary protection function, making it an obvious choice for the user:

- Reverse rotation protection
- Motor overheat protection
- Overcurrent protection
- Phase loss protection
- Low current protection

AuCom's Other Pumping Unit Solutions Hong Kong Swire Properties Downtown Complex: The AuCom Soft Start and Soft Stop eliminates damage to the piping system caused by liquid hammer action.
Canterbury, New Zealand: Soft start ensures that large irrigation systems can operate successfully in remote areas where power supply is limited.
Mt Buller Ski Field, Victoria, Australia: Soft start minimizes snow generator pump set-up requirements.
These are just some examples of the use of AuCom soft starter devices in many pumping applications. If you need to provide a design solution for motor control, please contact us.