Real-World Tests for Industrial Pressure Transmitters
You are probably aware that electronic devices receive a basic quality-control check before they go to market, but you might not be aware of the extensive testing that top-flight companies such as WIKA Instrument perform on their electronic pressure measurement devices. Unlike some manufacturers that perform only a single quality-control check on a product, WIKA believes all of its pressure transducers and pressure transmitters should be thoroughly tested under the real-world conditions they will be used in. Pressure measurement devices are used in industrial applications and require exhaustive testing to make sure they are water resistant, shock-resistant, and able to handle environments and temperatures ranging from frozen tundra to the burning sands of the Sahara. Pressure transmitters and transducers need to withstand extreme conditions to provide reliable performance.
WIKA Mobile Hydraulic Pressure Transmitter Quality Control Test Procedure
WIKA performs 80 separate quality-control tests on its mobile hydraulics pressure instrumentation. Here is a summary:
Initial functionality tests: These tests include a zero-point functionality test and an initial-temperature stress test. The initial-temperature stress tests include storage at 110˚ C for 48 hours and at minus-40˚ C for 24 hours.
Lifetime at nominal pressure test: This test involves load cycling at various temperatures. Each individual pressure transmitter is tested for 8 million cycles at 20˚ C, 1 million cycles at minus-40˚ C, and another 1 million cycles at 120˚ C.
Temperature tests: WIKA performs a battery of six temperature tests on most pressure transmitters, including ice water, dry heat, condensation , humidity, freezing, and rapid-temperature cycling tests.
Ingress protection tests: Devices designed to meet the ingress protection IP69K rating must withstand 10 seconds of a jet of 2100 psi (150 bar) pressurized water, while devices designed to meet IP67 are tested after being submerged in 1 meter of water for 30 minutes.
Chemical-resistance tests: WIKA has a three step chemical-resistance test process. The first step is a salt-spray test, in which a 35˚ C 5% salt solution is sprayed over the pressure transmitters for 96 hours. The second step is an ozone resistance test, where the devices are exposed to dry and liquid-phase ozone at 50˚ C for six hours. The third step is the chemical-resistance test, which applies hydraulic oil, brake fluid, gasoline, and other chemicals on the surface of the transmitters.
Shock and vibration tests: Shock tests include a single-shock test, continuous-shock test, and a drop test. Vibration tests include short-term vibration, long duration vibration, and broadband noise including temperature-superposition tests.
EMC tests: WIKA’s EMC quality control check includes an electrostatic-discharge test and a noise-resistance test.
Electrical tests: All devices must also pass a battery of electrical tests, including over voltage resistance, reset behavior, load-dump, and slow-load-dump tests.