DeFelsko PosiTest LPD Notice D'instructions page 2

The PosiTest Low voltage Pinhole (Porosity) Detector (LPD) is a
handheld electronic instrument designed to locate small defects and
discontinuities (called "pinholes" or "holidays") in a protective
coating system applied to a conductive substrate. Fundamentally,
the PosiTest LPD consists of a power source, a ground wire, a
probing electrode (a moistened sponge) and a multi-function LED
display.
In use, an operator moves the moistened sponge (electrode) over
the coated surface. When a pinhole is encountered, current flows
from the sponge through the moisture in the hole and into the
substrate below. The current is returned to the detector through the
attached ground wire, completing the circuit and triggering audible
and visible alarms.
To perform its intended function, a coating must be applied as a
continuous film. Pinhole (holiday) detection is useful for locating
pinholes, holidays, cracks, etc. which are not readily visible. Low
voltage pinhole detectors are commonly used to inspect non-
conductive coatings thinner than 500 µm (20 mils) applied to
conductive substrates.
IMPORTANT:
DeFelsko recommends that the operator read and
fully understand this manual prior to using the PosiTest LPD.
WARNING:
This equipment generates voltage. Accidental contact
with the electrode may result in a mild electric shock. The PosiTest
LPD operator should exercise all due care to minimize their risk of
electric shock and be aware of all relevant safety guidelines before
operating this equipment.
Introduction
Introduction
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