TP4 -

TP4 - High-voltage wiring harnesses

With sub-project 4 (TP4), the SILS specifically expanded its standardization work into the area of high-voltage (HV) wiring harnesses. While the first version of the standard (V1) concentrated on unshielded low-voltage cables, the focus now shifted to applications that are of central importance in modern electric vehicles - especially in high-voltage technology. Today, these systems work with on-board voltages of up to 800 volts and connect components such as batteries, power electronics and electric motors via specialized cable sets.

High-voltage wiring harnesses differ fundamentally from the LV range in several respects:

They are predominantly designed as point-to-point connections, are often shielded, have larger conductor cross-sections and require specific connection, testing and protection technologies. The safety level is also higher - thermal, electrical and mechanical loads must be consistently taken into account in the design.

At the beginning of its work in phase 2, TP4 first reviewed all existing design guidelines from the LV sector and checked their applicability to HV applications. The first specific HV guidelines have already been incorporated into standard version 2 - an important step towards being able to systematically map the high-voltage sector in a standardized manner.

With a view to standard version 3 (V3), the focus is now on the systematic development of our own GRs for high-voltage components and wiring harnesses. A comprehensive catalog of topics is already available and is being developed step by step. The content ranges from guidelines for cable design and shielding to distribution concepts and component-specific requirements for connectors and insulating materials.

Another development goal is to transfer the degree of standard conformity (DDA) to the HV area. The evaluation logic must be adapted for this - as many parameters from the LV area, such as the number of branches or block loadings, do not play a role in HV wiring harnesses. Instead, the new DDA logic takes into account the specific conditions of point-to-point connections and thus creates an objective evaluation basis for HV designs.

Another innovation component in TP4 is an accompanying R&D project on the laser marking of HV cables. In cooperation with a leading manufacturer (Domino Laser), different cable types were laser-marked in order to test the suitability of different jacket materials. The aim is to define the requirements for standardizable, automatable post-printing processes - without compromising confidential know-how. In addition to the standard, the results will also be incorporated into an accompanying white paper that will provide industry-wide guidance.

TP4 provides DIN 72036 with a viable extension into the high-voltage sector. The results of this sub-project lay the foundation for ensuring that high-performance electrical connections can also be designed in a standard-compliant, testable and automated production process in the future.

TP4 combines automation potential and technological progress - and makes the standard connectable for the electric driving of tomorrow.