DeFelsko PosiTest HHD, Инструкция по эксплуатации

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Introduction
1
The
PosiTest High voltage Holiday Detector
(HHD) is a Pulse
Type DC Holiday Detector designed to locate small defects and
discontinuities (called “pinholes” or “holidays”) in a protective
coating system applied to a conductive substrate. High voltage
holiday detectors are commonly used to inspect non-conductive
coatings thicker than 500 µm (20 mils).
Designed for maximum versatility, the
PosiTest HHD
can be used
in either a stick-type or wand-type configuration (when used with the
optional wand accessory). www.defelsko.com/manuals/hhd
The
PosiTest HHD
has two primary operating modes:
1.
Standby Mode:
The detector is powered-up but not generating
a high voltage.
2.
Detection Mode:
The detector is generating a high voltage and
analyzing electrode voltage and current to determine if holidays
are present. Holidays can be detected when the charged
electrode is passed 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 voltage on the display while in use.