Tinker&Rasor M1/AC Product Instructions

CORROSION MITIGATION INSTRUMENTATION

P. O. BOX 1667 SAN BERNARDINO, CA 92402 TEL: [phone] FAX: [phone]

PRODUCT INSTRUCTIONS

MODEL M1/AC HOLIDAY DETECTOR

DESCRIPTION

The Model M1/AC Holiday Detector is a highly sensitive device designed to locate holidays (pin
holes, voids, etc.) in thin film protective coating of relatively high electrical resistance when such
films are applied to the surface of material of low electrical resistance. In these applications, such
as painted metal surfaces, the Model M1/AC Holiday Detector will locate these points very
accurately with an audible signal. This method of inspection of thin film is a non-destructive test
and will not injure the protective coating.

EQUIPMENT

The electrical components are housed in a thermo plastic resin case with closing lid for maximum
protection and the detector is equipped with on-off switch, LED light, wand terminal, ground
terminal, fuse receptacle, 110v AC cord. (For use with 240v AC, an appropriate cord will need to
be sourced locally). The detector operates from 110/240 volt 50/60 cycle AC line current and the
electrical design of the M1/AC Holiday Detector utilizes a sensitive relay which is activated by a
voltage regulated, solid state power supply.

The detector is a “non-destructive wet sponge” type holiday detector. The basic electronic design
of the Model M1/AC Holiday Detector is that of a very sensitive circuit which is energized by AC
power. When current of 500 or 700 (+/- 10/%) micro-amperes flows in the circuit, an audible
signal is actuated.

The test lead wire used in the wand handle and ground wire is capable of handling a minimum of
100 milliamps at 100 volts. If replacement or additional wire is needed, make sure it meets these
requirements. Up to 200’ length of ground wire does not adversely affect the detectors operation,
in most cases. If adding additional ground wire, 14 AWG stranded or equivalent is recommended.

The exploring electrode is open-cell sponge material and is conductive when saturated with a
wetting solution. The sponge electrode is attached to the non-conductive wand handle by means
of the bolt with knob, plastic sponge holder and backing plate.

The wetting solution should consist of
potable tap water and a wetting agent.
The ratio of one (1) ounce agent to one
(1) gallon tap water is recommended.

Tinker & Rasor WATER-WETTER© is

a non-sudsing wetting agent, available
in 8 oz. bottles, factory direct or
through stocking distributors.

Web: www.tinker-rasor.com E-mail: [e-mail]

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CORROSION MITIGATION INSTRUMENTATION

P. O. BOX 1667 SAN BERNARDINO, CA 92402 TEL: [phone] FAX: [phone]

PRODUCT INSTRUCTIONS

RECOMMENDED TESTING PROCEDURES
PRE-ELECTRICAL TEST PROCEDURES

The protective coatings should be dry and free of all contamination prior to electrical holiday
testing. Proper curing and drying time of the protective coating must be established prior to
conducting electrical holiday testing.

Note: Solvents retained in the protective coating film can cause erroneous indications (false

holidays) during electrical testing.

The dry film thickness should not exceed 20 mils when electrical holiday testing is done with the
low voltage Model M1/AC Holiday Detector. Film thickness should be determined with a non­destructive dry film thickness gauge to make sure limits are not exceeded.

Special Note: Ordinary tap water will generally suffice to dampen the sponge electrode,
provided the protective coating thickness does not exceed 10 mils. The factory
recommended practice is to use a wetting agent at all times, regardless of coating
thickness to 20 mils.

HOLIDAY DETECTOR ASSEMBLY

Assemble the Holiday Detector by connecting the wire leading from the handle to one terminal of
the detector and the plain end of the ground wire to the other detector terminal, located on the
side of the instrument case. Connect the saturated (see below) electrode by means of the metal
clamp on the end of wand handle. Plug the AC cord into a 110v AC outlet and turn the instrument
ON.

ELECTRICAL TESTING PROCEDURES

The sponge electrode should contain sufficient amount of wetting solution to assure moisture
penetration from the sponge electrode into any defect that may be present in the protective
coating. Excess wetting solution should be squeezed out of the sponge electrode.

Attach ground wire directly to the bare structure (substrate) under test. On coated steel
structures the ground wire must be directly connected to the bare metal.

On coated concrete structures the ground wire should be connected directly to the reinforcing
steel embedded in the concrete. If rebar is not present, a ground connection to the concrete can
be made by placing the bare end of the ground wire against the bare concrete surface and
anchor it down with a burlap bag filled with damp sand.

The ground wire can be checked quickly for proper connection by contacting the wetted sponge
electrode to the bare structure and observing an audible signal, indicating correct electrical
continuity of the holiday detector circuit.

The rate of inspection speed of the sponge electrode over the protective coated surface should
not exceed sixty (60) linear feet per minute. Using a double stroke of the sponge electrode over
each area assures better inspection coverage with less likelihood of any missed areas.

Web: www.tinker-rasor.com E-mail: [e-mail]

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