Description; Product Construction - AEMC 3711 User Manual

Ground Resistance Tester Models 3711 and 3731

Description

The Ground Resistance Tester, Models 3711 and 3731, measure ground
rod and small grid resistance through any season, without the use of
auxiliary ground rods. Clamp-on ground resistance testers are used in
multi-grounded systems without disconnecting the ground under test.
The Models 3711 and 3731 simply clamp around the ground conductor
or rod and measure the resistance to ground. By performing
measurements on intact ground systems, the user also verifies the
quality of the grounding connections and bonds. Resistance and
continuity of grounding loops around pads and buildings may also be
measured.
Both models include a current measurement function. The probe's high
sensitivity enables measurement of leakage current flowing to ground or
circulating in ground loops down to 1mA and neutral currents to 30Arms.
This feature provides additional information which is becoming vital as
distribution ground networks carry higher levels of noise and harmonics
which affect power quality.
Both models offer battery life information at power-up and Auto-Off for
power management. Additional features are also displayed on the large
LCD to ensure precise measurements. The Buzzer and Auto-Off features
may be disabled from the push-buttons at any time.
The Model 3731 offers an Alarm function and a Memory (logging)
function. In the Alarm mode, the probe will audibly and visually indicate if
the reading is beyond an input set point. The user may also have the
Alarm initiated above or below the set point. This Alarm feature permits
quick field checks where only "pass" or "fail" readings will suffice.
The Memory function logs up to 99 measurements (Ohms or Amperes).
This enables the user to conduct field surveys, and to retrieve and
analyze the readings at a later time. The alarm settings and stored
memory information are saved when the ground tester is turned off.

Product Construction

®
The Models 3711 and 3731 body cases are built of Lexan for rugged
®
use. The probe heads are encapsulated in a double-walled Lexan shell
(or equivalent polycarbonate) for extra strength and are reinforced at the
body interfaces for enhanced field reliability. Overall construction and
mechanical design ratings such as drop test, shock and vibration,
weatherproofing against water projections, meet or exceed IEC
(International Electrotechnical Commission) standards. The products
have also been designed to meet EN 61010.
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