DeFelsko PosiTest HHD

High Voltage Holiday Detectors

Detects holidays, porosity, pinholes, leaks, and other discontinuities in coatings, linings, and membranes using pulse or continuous DC

  • Available as a stick-type with pulsed DC or a compact wand style with continuous DC
  • Lightweight, ergonomic design provides comfortable all-day use, reducing operator fatigue
  • Regulated pulse or continuous DC voltage output that won't change under load- ±5% voltage accuracy
  • Voltage calculator feature-input the coating thickness to automatically calculate the required test voltage
  • Extensive electrode options-choose from a wide range of rolling spring and flat wire brush electrodes or use electrodes from other manufacturers with optional adaptors-custom sizes available upon request
  • Long Form Certificate of Calibration included with each instrument

Conforms to ASTM D4787/D5162/D6747/D7953/G62, ISO 29601, NACE SP0188/SP0274/SP0490, AS3894.1

DeFelsko PosiTest HHD Series: 3 Models Available

Product DeFeslko HHDKIT PosiTest HHD Kit DeFeslko HHDKITB PosiTest HHD Basic Kit DeFeslko HHDCKIT PosiTest HHD C Kit
DC Ouput Pulsed Pulsed Continuous
Output Voltage Range 0.5 - 35 kV 0.5 - 35 kV 0.5 - 30 kV
Output Voltage Adjustment 0.5 kV - 1 kV: 10 Volt Steps | >1 kV: 100 Volt Steps 0.5 kV - 1 kV: 10 Volt Steps | >1 kV: 100 Volt Steps 0.5 kV - 1 kV: 10 Volt Steps | >1 kV: 100 Volt Steps
Output Accuracy ±5% ±5% ±5%
Pulse Duration 10 μs 10 μs ---
Pulse Repetition Rate 30 Hz 30 Hz ---
Operating Temperature -20° to 60°C (-4° to 140°F) -20° to 60°C (-4° to 140°F) -20° to 60°C (-4° to 140°F)
Case Pelican Hard Shell Hard Shell
Included Electrode Rod 50 cm (20") 13 cm (5") ---
Shoulder Strap Included Optional ---
Battery Size 72 Wh Li-ion 36 Wh Li-ion 4 Li-ion 18650 Batteries
Typical Battery Life for selected rolling springs @ 10 kV Ø 12" 40 hrs. 16 hrs. 16 hrs.
Typical Battery Life for selected rolling springs @ 10 kV Ø 40" 30 hrs. 12 hrs. 12 hrs.
Unit Weight 1.6 kg (3.6 lbs.) 1.5 kg (3.3 lbs.) 0.74 kg (1.63 lbs.)
Unit Dimensions 64 cm x 6.4 cm x 13 cm | (25" x 2.5" x 5") 64 cm x 6.4 cm x 13 cm | (25" x 2.5" x 5") 33 cm x 10.8 cm x 8 cm | (13" x 4.25" x 3.1")
Case Dimensions 101 x 46 x 18 cm | (40" x 18" x 7") 104 x 39 x 14 cm | (41" x 15.5" x 6") 46 x 33 x 18 cm | (18" x 13" x 7")
  • To substitute a 13 cm (5") Short Electrode Rod, append '-S' to the product code (i.e. HHDKIT-S)

lineDeFelsko PosiTest HHD Series: Features line

  • Easy-to-use with bright, color LCD
  • Ready to measure - includes everything needed for testing
  • Audibly and visibly alerts when flaws/holidays are detected
  • Lightweight, ergonomic design provides comfortable all-day use, reducing fatigue
  • Voltage calculator feature - input the coating thickness to automatically calculate the required test voltage
  • Rugged, environmentally sealed ABS plastic enclosure
  • Weatherproof, dustproof, and shockproof
  • Included hard shell case with custom foam inserts for superior protection
  • Two year warranty
  • Built-in certified voltmeter (crest meter, jeep meter) displays and regulates the voltage at the electrode
  • Long Form Certificate of Calibration included with each instrument
  • Conforms to national and international standards including ISO, ASTM, and NACE
  • Strobe light and loud audible alarms emitted when a holiday is detected.
  • Loud audio alarm remains audible in noisy environments
  • Removable Smart lithium-ion battery
  • Press-and-hold Safety Trigger helps prevent accidental high voltage generation
  • 7.6 m (25') ground (earth) cable with locking connector and spring clamp
  • Shock proof/creep proof - internally sealed to minimize creep distance to high voltage components. Designed in accordance with IEC 61010-1.
  • A wide range of rolling spring electrodes and wire brushes are available. Custom sizes available upon request.
  • Industry-standard connectors and adaptors for compatibility with nearly all existing electrodes

DeFelsko PosiTest HHD Series: Videos

lineRelated Productsline

DeFelsko PosiTest HHD Verifier

  • Ideal for field / laboratory verification of pulse or continuous DC holiday detectors
  • Wide measurement range


Rolling Spring Electrodes

Rolling Spring Coil for 4" pipe (102 mm) OD HHDSPRING4
Rolling Spring Coil for 6" pipe (152 mm) OD HHDSPRING6
Rolling Spring Coil for 8" pipe (203 mm) OD HHDSPRING8
Rolling Spring Coil for 12" pipe (304 mm) OD HHDSPRING12
Rolling Spring Coil for 14" pipe (356 mm) OD HHDSPRING14
Rolling Spring Coil for 16" pipe (406 mm) OD HHDSPRING16
Rolling Spring Coil for 20" pipe (508 mm) OD HHDSPRING20
Rolling Spring Coil for 24" pipe (610 mm) OD HHDSPRING24

Please Note:Each spring includes two pre-installed spring couplers. A spring connector (HHDCONNECT) is required to attach the PosiTest HHD to the spring couplers. Custom sizes and bulk pricing available. Additional couplers (HHDCOUPLER - 2 pack) are available.


Flat Wire Brush Electrodes

HHD Flat Brush 51 mm/2" HHDFLTBRSH2
HHD Flat Brush 152 mm/6" HHDFLTBRSH6
HHD Flat Brush 203 mm/8" HHDFLTBRSH8
HHD Flat Brush 305 mm/12" HHDFLTBRSH12
HHD Flat Brush 610 mm/24" HHDFLTBRSH24
HHD Flat Brush 914 mm/36" HHDFLTBRSH36
HHD Flat Brush 1219 mm/48" HHDFLTBRSH48


Flat Wire Brush Electrodes

Half-Circle Neoprene Brush for 50-127 mm/2-5" pipe OD HHDHCBRSH5


Extension Rods

  • Choose between 13 cm (5") and 50 cm (20") rods


Electrode Adaptors

  • Connect to spring and brush electrodes from other manufacturers


PosiTest HHD Verifier

  • Standalone voltmeter (crest meter, jeep meter) for verifying the accuracy and operation of ALL pulse type and DC holiday detectors


Spring Couplers

  • Thread onto rolling springs and attach to the Spring Connector


Spring Connectors

  • Connect the PosiTest HHD to DeFelsko or SPY rolling spring electrodes


DeFelsko PosiTest HHD Series - Data Sheet
DeFelsko PosiTest HHD Series - Instruction Manual
Accessories for DeFelsko Inspection Instruments - Online Catalog


What is a holiday detector?

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 DeFelsko PosiTest HHD operate at voltages up to 35,000V and are typically used on coatings more than 500 µm (20 mils) thick.

What is meant by the term 'stick type' or 'wand' holiday detector?

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 DeFelsko PosiTest HHD is the first combination stick type/wand type instrument on the market. With the optional handheld wand accessory, the DeFelsko PosiTest HHD converts into a wand style instrument suitable for voltages less than 15k.

How is a high-voltage test performed?

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.

Why is porosity measurement important?

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.

How does the DeFelsko PosiTest HHD measure coatings on concrete?

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.

Are custom size electrodes available?

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

Are internal pipe, half-circle, and other types of electrodes available?

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.

What electrodes are compatible with the DeFelsko PosiTest HHD?

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

What is the DeFelsko PosiTest HHD Verifier?

The DeFelsko 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.

Is the DeFelsko PosiTest HHD Verifier necessary to use the DeFelsko PosiTest HHD High voltage Holiday Detector?

No. The DeFelsko 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.

Is the new DeFelsko PosiTest HHD compatible with PosiSoft solutions?

No. The DeFelsko PosiTest HHD does not record any data.

How is the DeFelsko PosiTest HHD calibrated at DeFelsko?

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

Are there any special shipping considerations for the DeFelsko PosiTest HHD's Lithium-Ion batteries?

The DeFelsko 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 DeFelsko PosiTest HHD for service or repair, DO NOT include any batteries.