The Necessity of Salt Spray Test in EV HV Connectors

Salt spray testing is an important part of any high voltage electrical connection systems. Whether it is for harness accessories, such as connectors, terminals, clips, or electric vehicle harness assemblies, the DV test (Design Verification Test) cannot bypass the salt spray test.
 

What is Salt Spray Test?

Salt spray testing is a procedure that simulates the corrosive effect of sea water on HV connectors. The test lasts for a period ranging from 48 hours to 96 hours and is performed under controlled conditions in special chambers. The objective of this test is to determine whether or not an HV connector can withstand prolonged exposure to salt sprays without any significant degradation in performance or structural integrity.
The test itself involves spraying salt solution at high velocity onto an EV HV connector while monitoring its performance over time using various parameters such as voltage drop, insulation resistance (IR), leakage current density etc., which are recorded at regular intervals during its duration.
How to Do Salt Spray Test: It mainly uses salt spray tester to create artificially simulated salt spray environmental conditions to assess the corrosion resistance of connectors or metal materials.
Salt Spray Test Equipment: There are two types of salt spray test equipment, one is a spray type tester, which is the most widely used corrosion testing equipment, and the other is a centrifugal salt spray tester.
Salt Spray Test Method: Salt spray test is mainly divided into the following four types.

The Importance of Salt Spray Test in High Voltage Connectors

Environmental factors such as salt spray and humidity in coastal areas will affect the use of electric vehicle connectors. Ensuring the uninterrupted connection and transmission of high voltage currents and signals in this environment is quite a challenge. When working in an environment containing moisture and salt, the metal structure of the automotive connector and the surface treatment layer of the contact may cause galvanic corrosion, which will affect the physical use and electrical performance of the board-to-board connector.
This requires high-voltage connectors with physical characteristics such as high sealing and durability to withstand the harshest environmental conditions.
The purpose of salt spray test
◆It is to verify the corrosion resistance of high voltage connectors. Electrical connectors are exposed to extreme conditions such as temperature, humidity and corrosive chemicals. Salt spray test is one such test which can help you evaluate the performance of your connectors under severe operating conditions after prolonged exposure to harsh environments such as marine environment, or outdoor applications where corrosion may be an issue.
◆It can also help you identify problems early on in production that would otherwise cause delays later on.
 

HV Connectors with Improved Resistance to Salt Spray

Connectors with improved resistance to salt spray are critical for the safety of EV HV connectors. The longer the connector can be subjected to salt spray test, the more reliable it is.
To test a connector's resistance against corrosion caused by salt spray, you need:
1. Prepare a saline solution with 5% sodium chloride and 95% water
2. Spray in a closed thermostat after atomization
3. Placing the EV connectors in the box for 96 hours
4.Observe the change of the tested sample to test its corrosion resistance

EV HV connectors play an important role in the development of electric vehicles, so it's important that they are able to withstand harsh conditions. Salt spray testing is one of the many ways we can verify the corrosion resistance of our high voltage connectors before they leave our factory.