When operating rolling stock, very high requirements are placed on the operability and continuity of energy supply from the traction battery. It is also necessary to ensure the full functionality of stationary elements around the railway track. All this is possible by a number of HIG insulation monitoring devices made by HAKEL company.

n the case of rolling stock, it is necessary to monitor any emerging insulation breakthrough on the body, which is then signalled to the vehicle control unit (VCU) well in advance before it may cause a short circuit in the power supply. HIG products for the DC side can be used here. At the same time, it is necessary to solve the traction container, which contains one inverter to drive one to two traction motors. AC / DC insulation monitoring devices are used to monitor the insulation in these cases.

Modern cars, not only railway transport, usually generate a voltage of 3 x 400 / 50 Hz V from the heating coupling distribution. In order to ensure that the network is actually separated from the vehicle body, insulation monitoring devices are used to alert the emerging insulation breakthrough in advance before the insulation resistance of the system falls below a dangerous limit.

IT systems can be found both in power supply traction converter stations and in security technology at rail crossings and signals. This means, it is necessary to solve each application individually. They can be found on both track and station security and communication systems. Voltage conditions on these power supply systems are different, we encounter low DC voltage networks for backup accumulators, but also with a 3 x 6 000 V distribution to supply non-traction consumption along a wide railway track. This means, it is necessary to solve each application individually. HAKEL company has developed a wide range of insulation monitoring devices for these purposes.


An integral part is the need to safely operate the railway traffic even in the winter months, when it is necessary to deal with the formation of icing and snow layer between the tongues of switch – rail switches in the track.
To prevent this, electric heaters of switches are installed to switches. Because the heating rods are installed directly in the track, a great mechanical stress and insulation degradation occurs here. Therefore, there is a risk of a conductive connection between the heating system and the rail and thus the formation of a dangerous contact voltage.