Higher voltages require longer creepage/clearance and higher dielectric strength to prevent what?

• A. Breakdown
• B. Corrosion
• C. Thermal expansion
• D. Color fading

Answer: (A)

The key idea is preventing electrical breakdown. As voltage rises, the electric field in air or along surfaces can become strong enough to ionize the medium, creating a conducting path that allows a dangerous arc or leakage current. Increasing creepage (along surfaces) and clearance (through air) distances lowers the field strength along potential paths, making arcing less likely. Dielectric strength is the material’s inherent ability to resist breakdown under high electric fields; using insulation with higher dielectric strength lets it withstand stronger voltages without failing. Together, longer distances and stronger insulation prevent breakdown. Factors like corrosion, thermal expansion, or color fading aren’t the direct electrical failure mode addressed by creepage/clearance and dielectric strength.