PosiTest® HHD

A holiday detector is a non-destructive instrument for detecting discontinuities in a coating system including holidays, pinholes, and cracks. Other names include porosity detector, continuity tester, and holiday tester.

There are two types of pinhole detectors: low voltage (wet sponge) and high voltage (spark tester). Low voltage detectors, like the PosiTest LPD, are typically used on coating systems less than 500 µm (20 mils) thick. High voltage spark testers, like the PosiTest HHD operate at voltages up to 35,000V and are typically used on coatings more than 500 µm (20 mils) thick.

A 'stick type' holiday detector is a standalone detector with internal battery power and electrodes that attach to the end of an extension rod (stick). 'Wand' or 'Belt-style' detectors typically have a separate battery pack carried on the belt or shoulder strap and electrodes that attach to a handheld wand. The PosiTest HHD is the first combination stick type/wand type instrument on the market. With the optional handheld wand accessory, the PosiTest HHD converts into a wand style instrument suitable for voltages less than 15k.

A high-voltage holiday test is performed by moving a charged electrode over the coated surface. When a holiday is encountered, current flows from the electrode into the substrate. The current returns to the detector through the ground (earth) wire, completing the circuit and triggering audible and visible alarms. An integrated peak reading voltmeter measures and displays the output voltages on the display while in use.

After a protective coatings has been applied, it is important to ensure there are no defects or discontinuities present that expose the substrate beneath. Small areas of thin or missing coating, called 'pinholes' or 'holidays', can become foci for corrosion and drastically reduce the life of a protective coating system. They can be invisible to the naked eye. Porosity detectors are often used in applications where corrosion is difficult to monitor, or in aggressive service environments where performance of the protective coating is critical.

When measuring coating thickness, concrete is not considered a 'conductive' substrate, as it is much less conductive than metal. However, concrete is still slightly conductive, and can carry enough current to allow holiday detectors to function. Therefore, for the purposes of holiday detection, concrete is considered a 'conductive' substrate.

Yes. DeFelsko manufactures a wide variety of rolling spring and flat wire brush electrodes. Custom sizes are available upon request.

At launch, flat brush and spring electrodes will be available in pre-stocked and custom lengths, in addition to the handheld rubber paddle and fan brush. DeFelsko plans to add additional types of electrodes in the future, based on demand. If you have a request for an electrode configuration not currently offered by DeFelsko, please let us know.

The PosiTest HHD offers industry-standard connectors and adaptors for compatibility with nearly all existing electrodes including SPY, PCWI and Tinker & Rasor.

The PosiTest HHD Verifier is a calibrated voltmeter (crest meter, jeep meter) ideal for verifying the operating voltage of both Pulse and Continuous DC holiday detectors in the range from 500 to 35,000 Volts.

No. The PosiTest HHD features a built-in voltmeter (crest meter, jeep meter) with a traceable Long Form Certificate of Calibration. However, some standards call for a standalone voltmeter.

No. The PosiTest HHD does not record any data.

Each PosiTest HHD is calibrated using instruments traceable to a National Metrology Lab. A Long Form Certificate of Calibration containing actual measure values is included with every instrument.

The PosiTest HHD and one additional spare battery (charged less than 30% of capacity) can be shipped via surface and air transport on the major carriers (UPS, FedEx, and DHL) to all countries, subject to additional labelling requirements.

Note: When returning the PosiTest HHD for service or repair, DO NOT include any batteries.