Aerospace Conductor Surface Spacing on Dielectric Material
ARP7215
An SAE ARP (Aerospace Recommended Practice) document for the application of aerospace HV design standard for surface creepage (quantified for VDC, VAC, and frequency effects) including altitude and testing approach. Considering HV insulation system surface spacing with altitude affect testing approach and Test Article design to develop guidelines for material and spacing for voltage and altitude. Develop a testing procedure and dielectric test article for surface creepage with adjustable spacing. Initial testing effort using AC Vrms at a variety of altitudes, then expanding testing standard to DC, transients, temperatures, etc.
Rationale: Aerospace HV application design standards require creepage spacing to be verified with voltage at altitude. Dielectric (PCB) surface creepage distance for design spacing aerospace standards are ‘covered’ with IPC-2221 guideline. Existing high voltage (HV) application design spacing rules / guidelines at altitude are not verified for insulation surface creepage with modern materials. Propose Application: Initial testing with AC Vrms (50 Hz / 60 Hz) values to start AIR7502, Table 1, Level 3 to maximum of the lower limits of Level 5, at altitude. Then refine the testing to consider other application effects like pollution/contamination, coatings, etc.
