Holiday Detectors

Holiday Detectors for Anti-Corrosive Coating Inspection

A holiday detector identifies pinholes and other discontinuities in electrically insulating anti-corrosive coatings on metallic pipes and surfaces. It helps locate coating defects that expose the underlying metal, allowing them to be repaired before installation or further use.

How does a holiday detector work?

The instrument’s earth connection is attached to the metallic surface, and a high-voltage electrode is passed over the coating. When the electrode encounters a discontinuity, an electrical discharge can occur through the defect to the metal. An audible buzzer and a visual fault indicator alert the operator to its location.

The appropriate detector and test voltage depend on the coating type, thickness and applicable inspection requirements. Associate Electronics offers portable and stationary models, with specifications and downloadable catalogues available below.