# Normative References
This chapter is incomplete - still being written/defined.
When practical, this standard attempts to harmonize with existing global standards. Some of those standards are only available from proprietary sources that require them to be purchased. This conflicts with the goal of this standard to provide free access to information. To resolve this conflict, this standard attempts to provide enough information for developers to create conforming products without requiring reference to proprietary standards. Nevertheless, in cases where this standard is not sufficiently clear, it may be useful to reference such a proprietary standard to which this standard is harmonized. The developers welcome feedback to further clarify this standard and minimize any dependencies on proprietary standards.
# Harmonized Standards
ISO/DIS 21780 - Road vehicles — Supply voltage of 48 V — Electrical requirements and tests.