Extech Instruments 382152 User manual

User's Manual
Earth Ground Resistance Tester
Model 382152
Introduction
Congratulations on your purchase of the Extech Earth Ground Resistance Tester. This
device can measure resistance (in 3 ranges) and AC voltage to 200V. 2mA constant
current test signal permits earth resistance tests without tripping current breakers in the
circuit under test. Single, momentary tests or automatic 3-minute tests can be selected.
This device was designed to meet IEC-1010 (EN 61010) safety standards.
Earth Ground Resistance Testers are useful for:
•Estimating ground resistance of a proposed substation or transmission tower.
•Computing inductive coupling between neighboring power and communication
circuits.
•Designing cathode protection systems.
•Geological surveys.
Careful use of this meter will provide years of reliable service.

Model 382152 Ver. 1.6 April 2001
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Warranty
EXTECH INSTRUMENTS CORPORATION warrants this instrument to be free of defects
in parts and workmanship for one year from date of shipment (a six month limited
warranty applies on sensors and cables). If it should become necessary to return the
instrument for service during or beyond the warranty period, contact the Customer
Service Department at [phone] for authorization. A Return Authorization (RA)
number must be issued before any product is returned to Extech. The sender is
responsible for shipping charges, freight, insurance and proper packaging to prevent
damage in transit. This warranty does not apply to defects resulting from action of the
user such as misuse, improper wiring, operation outside of specification, improper
maintenance or repair, or unauthorized modification. Extech specifically disclaims any
implied warranties or merchantability or fitness for a specific purpose and will not be
liable for any direct, indirect, incidental or consequential damages. Extech's total liability
is limited to repair or replacement of the product. The warranty set forth above is
inclusive and no other warranty, whether written or oral, is expressed or implied.
Safety
Please read the following safety information carefully before attempting to operate the
meter and use the meter only as specified in this manual.
Environmental safety information
•Do not use meter outdoors when precipitation is likely
•Installation Category III
•Pollution degree 2
•Altitude: 2000 meters max.
•Ambient conditions: 32 to 104oF (0 to 40oC); RH: 80% max
•Observe the following international safety warning symbols
Safety Symbols
Caution: Refer to this manual before using this meter
Dangerous Voltages
Meter is protected throughout by double or reinforced insulation
Organizations that provide rules and guidelines for proper grounding
•The National Electrical Code (NEC)
•Underwriters Laboratories (UL)
•National Fire Protection Association (NFPA)
•American National Standards Institute (ANSI)
•Occupational Safety Health Administration (OSHA)
•Telecommunications Industry Standard (TIA)

Model 382152 Ver. 1.6 April 2001
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Specifications
Measurements Earth ground resistance (in 3 ranges) and AC voltage to 200V
Display 3-1/2 digit (1999 count) LCD with LED test status indicator
Data hold Freezes latest reading on the LCD display
Automatic Test 3 minute test timer with automatic power down
Measurement trigger Push-button single reading or 3 minute automatic test lock
Test lead length Red: 50' (15m), Yellow: 33' (10m), Green: 16' (5m)
Power supply Six 1.5V 'AA' batteries (included)
Low battery indication LCD displays 'B' icon
Over-range indication '1' displayed as most significant digit
Safety IEC-1010 (EN-61010) category III
Weight 27.7oz. (800g) with batteries
Dimensions 6.42 x 3.94 x 2" (163 x 100 x 50 mm)
Supplied accessories Test leads (3), auxiliary earth bars (2), six 'AA' batteries,
and carrying case
Range Specifications
Measurement Range Resolution Accuracy
Earth Ground Resistance
2mA test current (820Hz)
20, 200, 2000Ω 0.01Ω, 0.1Ω, 1Ω
± (2% rdg + 2 d)
Earth Voltage
Frequency: 40 to 500Hz
0 to 200VAC 0.1V ± (1% rdg +2d)
Meter Description
1. Earth ground test lead terminal
2. Test status LED
3. Data Hold switch
4. Automatic 3-min. test OFF button
5. LCD Display
6. C1, P1 Aux bar test lead terminals
7. Function select switch
8. Resistance range select switch
9. Push-button momentary test
10. Automatic 3-min. test ON button
1
2
3
4
5
6
7
8
9
10

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Operation
Test Connection Diagram
Test Preparation and Setup
1. Connect the test leads to the meter as follows:
•Green lead to the 'E' terminal
•Yellow lead to the 'P' terminal
•Red lead to the 'C' terminal
2. Drive the Auxiliary Earth Bars C1 & P1 (included) into the ground. Align the bars
equidistant to the existing Earth ground connection and in a straight line as shown in
the diagram above.
3. Ensure that the bars are between 17 and 33 ft (5 and 10 meters) apart. If the auxiliary
bars are placed in close proximity to the ground stake, measurement inaccuracies will
result.
4. Connect the clamp ends of the test leads to the Earth bars and existing ground
connection spike as shown above.
Earth Voltage Test
1. Set the meter's function switch to the ACV position.
2. Press the PUSH-ON button to perform a single, momentary test.
3. Press the PUSH-ON and TIMER ON buttons simultaneously to begin a 3-minute test.
The 3-minute test automatically shuts down after 3 minutes. Press the Timer OFF
button to end an automatic test at any time.
4. The front panel test status LED will light if the test is operating correctly. If the LED
does not light check for problems such as open circuits or overload conditions.
5. Note the LCD reading.
6. Confirm that the voltage measurement is less than 10V AC; otherwise accurate Earth
resistance measurements cannot be made. If voltage is present (higher than 10V AC),
the source of the voltage must be found and corrected before testing can continue.
Bars
equidistant
17 to 33 ft
(5 to 10m)
apart
17 -33 ft
(5 -10m)
Existing
ground connection
Green
lead
Yellow
lead
Red lead
METER
C1
P1
Ground surface
E

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Earth Resistance Test
1. Set the meter's function switch to the ohms position and set the range switch to the
desired resistance range.
2. Press the PUSH-ON button to perform a single, momentary test
3. Press the PUSH-ON and TIMER ON buttons simultaneously to begin a 3-minute test.
3-minute tests automatically shut down after 3 minutes. Press the Timer OFF button to
end an automatic test at any time.
4. Note the displayed reading. The front panel test status LED will light if the test is
operating correctly. If the LED does not light, check for problems such as open circuits
or overload conditions.
5. If high resistance is detected, note the value and take appropriate steps to correct the
ground connection if necessary.
6. Readings between 300 to 600Ω(in the 2kΩrange) are typical when the test leads are
not connected to the meter.
Data Hold
Data Hold freezes the latest measurement reading on the LCD.
1. Select ON from the Data Hold selector switch to turn Data Hold ON.
2. The reading that was on the display when the switch was set is now held on the LCD.
3. The Data Hold function does not retain measurement data if the meter is turned off.
4. Select OFF from the Data Hold selector switch to return meter to normal operation.

Model 382152 Ver. 1.6 April 2001
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(
Tech Support Hotlines
781-890-7440 ext. 200
[email protected]
www.extech.com
Maintenance
Battery Replacement
When the low battery icon 'B' appears on the LCD, the meter's batteries must be changed.
1. Remove power and disconnect the test leads from the meter.
2. Remove the rear battery compartment screw with a Phillips head screwdriver.
3. Remove the battery compartment cover and replace the six 1.5V 'AA' batteries.
4. Affix compartment cover and tighten screw.
Cleaning and Storage
Periodically wipe the meter's case with a damp cloth and mild detergent; do not use
abrasives or solvents. If the meter is not to be used for a period longer than 60 days,
remove the batteries and store them separately.
Calibration and Repair Services
Extech offers complete repair and calibration services for all of the products we sell.
For periodic calibration, NIST certification or repair of any Extech product, call customer
service for details on services available. Extech recommends that calibration be performed
on an annual basis to insure calibration integrity.
Copyright ©2001 Extech Instruments Corporation.
All rights reserved including the right of reproduction in whole or in part in any form.