Ingun GKS-550 319 090 A 1000 Test Probe, Cupped Tip, 50mil

A fine-pitch INGUN spring-loaded test probe for the 1.27 mm (50 mil) grid, used to make temporary contact with a test point on a PCB during in-circuit and functional test. It seats in a matching KS-series receptacle in the fixture's probe plate, so a worn or bent probe can be pulled and replaced from the top without disturbing the wiring underneath.

Fine-pitch probes of this class are what make a dense test grid possible: a slim 0.78 mm barrel lets probes sit at half the centre spacing of a 100 mil (2.54 mm) part, while a full 4.3 mm of working stroke still absorbs board warp and fixture stack-up tolerance. The 0.9 mm tip is the mid-size face for this class — broad enough to spread contact load across a test pad without demanding the open keep-out a larger cone or crown would need — and the 1 N spring is the lighter of the two common forces, chosen to keep total board loading manageable when several hundred probes land at once.

• Tip diameter 0.9 mm (0.035 in); barrel diameter 0.78 mm (0.03 in)
• Grid pitch 1.27 mm (50 mil)
• Spring force 1 N at working stroke
• Working stroke 4.3 mm, maximum stroke 6.35 mm
• Contact resistance 20 mΩ typical
• Gold-plated plunger; replaceable from the top of the fixture