Functional safety test system

for medical applicationsmodularautomatic

Overview
Automated test system designed to verify safety and functionality of high-frequency surgery and lithotripsy devices after production. The system supports sequential testing of multiple user parts without replugging and records results centrally.

Industry
Medical technology

Challenge
Develop an automated tester capable of handling a large variety of device types while minimising connection errors and total test time; each DUT must be connected only once.

Solution
A configurable test station with multiple connection options was developed to enable sequential testing of several user parts (up to 5 for patient leakage tests) without replugging. Ground bond, hipot, insulation and functional tests are executed without changing connections. Personnel protection is provided by a three-sided light curtain with deflecting mirrors to allow side insertion/removal. A special text-view step permits operation of the DUT by test personnel during functional tests while keeping working voltage enabled despite light-curtain interruptions. PC software stores an unlimited number of test programs, assigns programs to DUTs via a product list and supports barcode-assisted program selection. Test reports are automatically saved in XML or Access format to network locations. An automatic daily dummy test verifies tester functionality and blocks further testing until successful.

Benefits

• Turnkey solution including DUT handling, adaptation and workplace design
• Simple, intuitive operation for semi-skilled staff
• Single connection per DUT; full test sequence runs automatically
• Automated network storage of test data to specified location/database
• Long service life and service-friendly design
• All values and settings adjustable via software
• Automatic daily dummy test that prevents testing until passed
• Workplace protection compliant with EN 50191
• Automatic test program selection (barcode)
• High test depth and coverage

Technical specifications

• Ground bond test: 10 A – 30 A via test pin or special housing connection
• Insulation test: up to 4 kV with freely switchable matrix over 8 points
• Hipot test: 5.5 kV AC / 6.0 kV DC / 100 mA (non-safety-current-limited) with freely switchable matrix over 8 points
• Function test: single-phase, measuring ranges 10 A and 20 A; records voltage, current, power and cos phi
• Earth leakage / contact current / patient leakage tests for up to 5 user parts with fault simulation; current ranges 10 mA, 1 mA and 0.1 mA; automatic zero correction for patient leakage in 0.1 mA range
• Multiple DUT handling: various connection options to test several user parts sequentially without replugging
• Personnel safety: three-sided light curtain with deflecting mirrors; special mode permitting DUT operation by personnel during function test
• Software: unlimited test program storage, automatic assignment to products, barcode-assisted program selection
• Data storage: automatic saving of test results in XML or Access format to network locations/databases
• Automatic daily dummy test required before normal testing proceeds