Sentinel 3520 — A Reliable, Repeatable System for Leak Testing Large Parts

When you’re struggling to balance accuracy, cycle time and Gage R&R for a complex leak test, the Sentinel 3520 is up to the challenge. It is a pressure decay and mass flow instrument particularly suited to large parts such as EV batteries, variable volume parts, and parts requiring temperature and other compensation— all while delivering speed, accuracy, and repeatability. This instrument offers advanced configurability using CTS partner company Sciemetric’s digital signature analysis software.

Performing in the Most Challenging Leak test Situations 

Many manufacturers struggle with leak test station accuracy, cycle time, and Gage R&R, particularly when faced with complex leak test requirements like large volume leak test, variable volumes, multi-cavity parts, low leak rates, and pressure stability. It is a top choice for EV battery testing.

These test scenarios require a precise balance of pressure control, flow range and fill rate to get an accurate reading and meet cycle time requirements, which the Sentinel 3520 delivers. 

  • Testing large parts, up to 1000L
  • Testing variable volume parts with multiple cavities
  • Uniquely compensating for temperature, atmospheric and barometric fluctuations affecting test
  • Achieving balanced accuracy, cycle time, and Gage R&R 
CTS Sentinel 3250 with sigPOD controller


Six reasons to use the CTS Sentinel 3520 for large part leak testing

Infographic: Six reasons to use the CTS Sentinel 3520 for large part leak testing

Advanced Leak Test Data and More Accurate Defect Detection Using PSV™ Software

The Sentinel 3520 is controlled by a sigPOD running Sciemetric’s PSV™ (process signature verification) software which measures thousands of datapoints during each test for more accurate pass/fail decisions. The sigPOD also allows you to access visualized control charts, histograms and other SPC tools right at the station. 

There are various options to export, store, and report on your data. The CTS QualityWorX Datahub allows you to consolidate data by part number, including process signatures from up to 5 test stations. It includes a license to Sciemetric Studio software, a manufacturing analytics software that lets you visualize and analyze test data. For a broader solution that collects data from more stations, take a look at QualityWorX and Sciemetric Studio.

Webinar: Sentinel 3520 Leak and Flow Test

The Sentinel 3520 is ideal for challenging leak test scenarios, such as large volume leak test, variable volumes, multi-cavity parts, low leak rates, and pressure stability. Learn more about its capabilities in this presentation

Leak and Flow Test Instrument: Test Types

Depending on your test needs, the Sentinel 3520 can be configured to meet your requirements for pressure range, flow meter range and flow configuration. The Sentinel 3520 supports the following test types:
  • Pressure/Vacuum Decay: Leak Standard
  • Pressure/Vacuum Decay: ΔP
  • Pressure/Vacuum Decay: ΔP/ΔT
  • Occlusion: Pressure or Vacuum
  • Ramp to Proof: Pressure (Burst Test)
  • Pressure Verify
  • Customizable Pressure / Flow Sequencing
  • Mass Flow (Flow Models)
  • Test Volume Verification (Flow Models)


  • Pressure measurement and control resolution down to ±0.000,01 psi
  • Flow measurement down to ±0.2 % of full scale
  • High flow fast fill up to 300 SLPM
  • Test parts from 1 cc to 1,000,000 cc in volume
  • Helium evacuate and fill
  • Customizable pressure and flow sequencing
  • sigPOD controller equipped with PSV software, using digital process signatures for advanced test analysis
  • Use the sigPOD controller to conduct an additional in-process test such as press-fit, weld or dispense monitoring


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  • Sentinel 3520 Brochure


  • Sentinel 3520 Specifications

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