Selection and Design of High-voltage Wire Harnesses Covering

Blog | news | Feb 03,2023

High-voltage wire harness coverings include corrugated pipes, self-rolling pipes (sleeves), wear-resistant tapes, heat-insulating sleeves, etc. To correctly select the high-voltage wire harness covering, it is also necessary to clarify the ambient temperature and high-voltage wire harness requirements. It is also the basic input of selection requirements.

High voltage wiring harness covering selection input

Ambient temperature

Due to the complex environment of the vehicle, the temperature requirements of different parts are also different. In the actual layout process of the HV, the wires will be routed in different parts of the vehicle, and different wiring harness designs should be carried out for different temperature requirements.

Make sure the HV wiring harness is working properly in this environment. The Working temperature, within this temperature range, the product can work for a long time and maintain the normal characteristics of the product.

Storage temperature, within this temperature range, the product can still be used normally after being installed on the vehicle after a period of reasonable storage.

HV Harness Requirements

Appearance color: The appearance of the HV harness is usually orange.

Wire surface coating: Since the wire harness is usually fixed along the body sheet metal, in order to better protect wire harness, bellows, plastic wear-resistant pipes, etc. are usually used to protect the wire harness.

When the wiring harness passes through the engine environment or other high-temperature environments, it will use heat insulation sleeves and other protection.

Design of wire slot support for high voltage wire harness

We need to do a good job in the selection and design of the wiring harness covering according to the actual environment of the vehicle wiring harness.

Harness protection (wire duct, etc.)

When the wire harness is inevitably exposed to the outside of the vehicle during the wiring harness layout process, it is more common to route the wires under the chassis.

Stone impact resistance requirements for wire slots: In many cases, wire slots are used under the chassis of vehicles to protect wire harnesses from being damaged by stones, so it is necessary to specify stone impact resistance tests for wire slots.

High-voltage wire harness coverage selection design

The selection of the cover should meet the basic requirements of the ambient temperature and wiring harness design.


In general, the HV wire harness needs to be protected by a coating, and a corrugated tube can be used if there is no special requirement.
Bellows selection, the color should be orange.

Corrugated pipe diameter = wire outer diameter/0.92 (when multi-strand wires are used, the outer diameter of the wire is the diameter of the outer common tangent circle)

In addition to the commonly used circular bellows, there are also elliptical bellows, which are usually suitable for multi-line common bellows. the


Sleeves can effectively prevent the wear of the wire harness. Compared with the bellows, the wear resistance of the sleeve is higher and the outer diameter is smaller, but the cost will increase.

The color of the sleeve should be orange. There are open self-rolling and closed-end. The open self-rolling type is more convenient to install. When selecting the open self-rolling type, it should be noted that the overlapping rate of the curling should reach 30% (range), and the specific overlapping rate of the curling should be determined with the corresponding supplier.

Wear-resistant tape

Compared with bellows and Sleeves, the wear-resistant tape is easy to use, and the added wire harness size is the smallest, which hardly affects the wire harness size, and the cost is lower. However, it is rarely used in general, and it can be used in situations where the environment requirements are not high, such as in the line slot and inside the device.

Heat insulation sleeve

Excessive temperature will affect the normal operation of the high-voltage wire harness. To avoid this situation, when the wire harness is located in a high-temperature area, such as near the three-way catalytic converter as shown in the figure, you can use a heat-insulating sleeve to insulate the heat, or at the same time。

When the exhaust pipe is routed in parallel when the gap between the high-voltage wiring harness and the heat source is less than 100mm, heat insulation protection must be done. Common heat sources: exhaust pipe, EGR exhaust gas recirculation valve, oxygen sensor, three-way catalytic converter, etc.

Sponge tape

For areas with large vibration amplitude and low vibration frequency, sponge tape can be used. In addition to shock absorption, sponge tape can also reduce noise, but its wear resistance is relatively poor.

High-voltage wire harnesses are used in a wide variety of applications, from aircraft and automobiles to military vehicles and spacecraft. The harnesses are designed to protect the wires from damage and to prevent electrical shorts.

The selection of the right wire harness covering is critical to the performance of the system. The cover must be able to withstand the forces exerted by the wires, as well as the temperatures and chemicals to which it will be exposed. If you have any questions about the high-voltage wire harness, you can contact us, and our professional team will answer you

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