Detect holidays in protective coatings with PosiTest HHD and PosiTest SHD porosity detectors

Detect defects in protective coatings with the unique PosiTest HHD and PosiTest SHD porosity detectors.

There are two ways to locate imperfections and cracks (“holidays”) in a coating system:

With low voltage pinhole detectors like the PosiTest LPD and high voltage pinhole detectors like the PosiTest HHD.

Background information on the detection of defects or holidays

Use of the porosity testers DeFelskon PosiTest HHD and PosiTest SHD

Before testing, the porosity detector is grounded to an area of the bare metal substrate. High-voltage pulsed porosity detectors such as the PosiTest HHD can also be grounded using a ground wire, grounding wrist strap, or grounding mat. For concrete substrates, the ground wire is attached to the rebar or other metallic ground permanently installed in the concrete. If there is no metallic grounding, the grounding cable is laid on the uncoated concrete surface. The device outputs a voltage and charges the electrode as it moves across the coating. When a defect is detected, current flows from the electrode into the substrate below. The current flows back to the pore detector / pore tester via the ground wire, which closes the circuit and sets off an alarm.

Whether a low voltage or high voltage pinhole detector should be used depends on the thickness of the coating being applied.

For coating thicknesses up to 500 μm, low-voltage porosity detectors (according to the wet sponge method) are generally used.

High voltage pinhole detectors are used on coatings with a total thickness of 8 mils (200 μm) or more.

Solutions for porosity testing from DeFelsko and mtv messtechnik

DeFelsko offers low and high voltage pinhole detectors for finding imperfections in non-conductive coatings and plaques applied to electrically conductive substrates. These devices conform to ASTM, NACE, ISO, and other standards for flaw detection. A long-form calibration certificate is supplied with each device at no extra charge.

Buy Low voltage porosity detectors

PosiTest LPD low voltage porosity detectors are suitable for coating systems with a total thickness of up to 500 μm.

Buy High-voltage porosity detectors

PosiTest HHD high voltage porosity detectors are suitable for detecting voids in coating systems with a total thickness of 200 μm or more.