TP4 –

High voltage wire harness

Extension of the standard to include high voltage applications

Contact

Helmut Wichmann

Coroplast Fritz Müller GmbH & Co. KG

Mr. Wichmann is Director Global Product Management & Marketing Wires & Cables

DESIGN RULES FOR HIGH VOLTAGE WIRE HARNESSES

Extension of the standard to include high voltage applications

In the first edition, DIN 72036 was limited to the use of low-voltage wiring harnesses with unshielded cables. However, a large number of applications are served in a vehicle, which in turn require specific components and cables.

One of these applications is electric driving and the high-voltage systems developed for this purpose, which currently use up to 800V on-board voltage. The various core components such as the battery, motors and power electronics are connected with special high-voltage wire harnesses. These are easily recognizable in orange.

 

Initial situation and motivation

Developments in the field of electric driving and the associated need to massively increase the voltage level in the vehicle are leading to a veritable boom in new high-voltage components and manufacturing processes. Due to the enormous speed at which this development is taking place, manufacturing aspects that allow simple and automated production are often not given sufficient consideration.

At present, OEMs and assemblers in particular have to deal with a whole bundle of possible technologies and, unlike in the low-voltage sector, they cannot rely on decades of experience in the development and construction of wire harnesses. In particular, the much larger cross-sections and the use of shielded cables pose new challenges for production.

It is therefore a good time to promote the emerging consolidation of technologies in wire harness production towards full automation with the expansion of DIN 72036 to include high-voltage wire harnesses.

 

Current focus of work

  • In the first step, all low-voltage design guidelines are reviewed and evaluated for their direct applicability to high voltage. There are four different assessments.
  • The design rule is applicable without restriction and without amendment.
  • The design rule is applicable with few changes.
  • The design rule is transferable with comprehensive revision.
  • The design rule is not relevant for high voltage.

This assessment results in a worklist that is to be completed by the next update of the standard. The design rules that require few to no changes are the easiest to implement. Here, either only the application level is added or a few changes are made to the content. Ideally, the design rule can remain valid for LV despite these few changes.

In the event of major changes, a new design rule is derived and drawn up. This requires intensive coordination within the TP as well as with other TPs, as the applicability of new design rules to low voltage and high frequency wiring harnesses must be clarified.

 

Outlook

With the structured recording of common components and manufacturing processes of a HV wire harness and their systematic linking, gaps in the standard can be uncovered that can be closed in a targeted manner with new design rules. The aim here is to record as comprehensively as possible all aspects that are necessary for the fully automated production of HV wire harnesses.