Fundamentals of electrics and high voltage technology

Protection measures in HV vehicles

In an IT system (IT: French Isolé Terre), the conductive housings of the equipment are grounded but the energy source is not. The high-voltage drive systems of electric and hybrid vehicles are designed in this way. For example,  the housings of the inverter and the electric motor are connected to each other via the chassis. This connection represents the equipotential bonding.

The essential features of such a system include the permanent monitoring of the insulation resistance and a low-resistance potential equalization resistance.

LEYBOLD offers all required components as plug-in elements, which are operated on a 24 V low voltage level for the harmless examination of such systems.

Voltages as well as the equipotential bonding resistance can be measured directly with Sensor-CASSY 2, the insulation resistance is determined and evaluated with a specially designed measuring device.