When designing electronic or mechanical enclosures, ensuring protection against dust and water ingress is crucial. This is where IP (Ingress Protection) standards come into play. IP ratings classify the degree of sealing effectiveness of enclosures against dust, debris, and moisture. Your test specifications (test pressure, volume, leak rate) will dictate the specific IP rating (ie. IP44, IP67, IP69, etc) and test method used to test to that rating.
One of the most commonly used IP ratings is IP67, which certifies that a component is dust-tight and can withstand temporary immersion in water.
Common industries and applications that rely on IP67 testing include consumer goods (cellphones, watches, cameras, etc), vehicle ECUs, auto sensors and cameras, hard drives, medical devices, and many more.
In this post, we'll walk through how to properly leak test closed components to meet IPXX standards, with a focus on practical methods for achieving compliance with IP67.
Closed Component Leak Testing Method
The method most used to leak test products to IP67 (and IPXX) standards is the closed component method, also referred to as the “dosing method”, or “dump testing”. Closed component testing can be used for nearly anything without test port, which can be pressurized (if a part is too flexible, pressurization will interfere with accurate test results).
The test process
Closed component testing requires a leak test computer and a test chamber. The test specimen is placed in a measuring chamber (bell). This chamber is then closed and the test can begin.
This measuring chamber is not directly pressurized with positive or negative pressure but is dosed via a previously evacuated or filled pre-volume. The volume between the test specimen and the measuring chamber is known, so that a defined pressure ratio is expected.
Any leakage in the test specimen changes this ratio and thus leads to a change in pressure, which is recorded and evaluated by means of a pressure sensor (this sensor could be a pressure sensor transducer or a pressure difference sensor). IP67 testing generally uses a pressure difference sensor, while the standard pressure sensor transducer may be used for very small leak rates.
The principle of the dosing method can also be integrated into other measuring methods to perform a volume determination, a component interrogation or an exact gas quantity determination.
The Importance of Proper Fixturing
The closed component leak test method requires both the leak test machine and custom fixturing. This includes the test chamber, seals and connectors, etc. To ensure accurate, fast pressure testing, the test chamber must be designed to fit around the specific part being tested as close as possible to minimize the empty space around the part—thus allowing the chamber to pressurize quickly and leaks to be clearly identified during the test. Every part is slightly different, so the test chamber needs to be designed to the specifications of each part for the most accurate, repeatable leak test results.
Rely on innomatec’s Expertise and Full Solutions
The best way to ensure an accurate, repeatable IP67 (IPXX) test is to source a full solution, including the leak test computer, custom chamber and fixturing. innomatec is equipped with the technology and expertise to deliver a full solution built specifically with your need and optimized for the absolute best possible performance. This means you can begin testing right away and have the utmost trust in your results!
Use the NEW LTC-503 for Fast, Economical Closed Component Testing
Have questions about closed component leak testing or meeting IP67 (IPXX) standards? Contact the experts at innomatec! We’re here to help.