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Clamp-On Ground Resistance Testers Models 3710 and 3730 USER MANUAL Chauvin Arnoux, Inc. d.b.a. AEMC ® Instruments 99-MAN-100061 Rev 05 03/98...
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Clamp-On Ground Resistance Testers Models 3710 and 3730 USER MANUAL HOLD HOLD AEMC AEMC Model 3710 Model 3730 GROUND TESTER GROUND TESTER I N S T R U M E N T S I N S T R U M E N T S...
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Owner’s Record The serial number for the Model 3710 or Model 3730 is located inside the battery compartment of the instrument. Please record this number and purchase date for your records. CLAMP-ON GROUND RESISTANCE TESTER MODEL 3710 CATALOG #1221.01 SERIAL #:...
• Open and close the clamp-on jaws slowly ensuring proper alignment. • AEMC ® Instruments considers the use of rubber gloves to be an excellent safety practice even if the equipment is properly oper- ated and correctly grounded. Ground Resistance Tester Models 3710/3730...
“egg crate” foam on the inside of the carrying case cover. Government Orders The Clamp-On Ground Resistance Tester Model 3710 (Cat. #1221.01) has been issued a National Stock Number. Orders for the Model 3710 should reference NSN 6625-01-377-8030. Accessories One multiple calibration loop, Cat. #1223.01...
Clamp-on ground resistance testers are used in multi- grounded systems without disconnecting the ground under test. The Models 3710 and 3730 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.
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The LCD lens cover may be easily replaced if scratched. The sealed push-buttons directly access all test functions and are easily operated even with gloved hands. Lexan ® is a registered trademark of General Electric Corporation. Ground Resistance Tester Models 3710/3730...
Current Measurement Frequency: 47 to 800 Hz Current Overload: OL displayed above 30 A rms MECHANICAL SPECIFICATIONS Dimensions: 9.25 x 3.94 x 2.17" (235 x 100 x 55 mm) Weight: 2.2 lbs. (1 kg) Case Material: Lexan ® 920A (UL94V2) Ground Resistance Tester Models 3710/3730...
Working Voltage: 150 V, Cat. III - Pollution Degree 2 300 V, Cat. III - Pollution Degree 1 Max A Overload: 100 A continuous, 200 A (< 5s) 50/60 Hz OL displayed above 30 A rms Calibration Cycle: Calibration once a year is recommended Ground Resistance Tester Models 3710/3730...
5. Ω: Resistance measurement 2. Hold: Freezes last measured value on the display 6. A: Current measurement 3. Display: 3000 count LCD, 7. Lever: Opens or closes jaws function indicators Ground Resistance Tester Models 3710/3730...
8. AL: Activates/deactivates the Alarm function, access the value of the Alarm setpoint in program mode 9. MEM: Stores the reading into memory, reads Memory Recall (MR) values and clears the memory in recall mode Ground Resistance Tester Models 3710/3730...
(the instrument is measuring a metallic loop and not the ground electrode resistance). In this situation, electrode resistance measurements may not be valid. Current measurement mode. mA, A Ground resistance measurement mode. Ground Resistance Tester Models 3710/3730...
Memory recall register. Displays the numbered value being recalled from memory (1-99). Note: Models 3710 and 3730 share the same LCD and display all segments at power-up. Functions not available on the 3710 are displayed at power-up.
Function Controls Model 3710 and 3730 share common functions (On/Off, A, Ω , Auto-off, Buzzer disable, Hold). Even though the Model 3710 is shown in the examples for these functions, the controls will respond identically for the Model 3730. On/Off The ON/OFF push-button, when pushed actuates power on or power off with an audible control tone.
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I N S T R U M E N T S Beeper Disable To disable the beeper, press the ON and Ω together at power-up. The Ω indicator will disappear from the LCD. (Fig. 8) Figure 8 Ground Resistance Tester Models 3710/3730...
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400 to 600 Ω 10 Ω 600 to 1200 Ω 50 Ω Figure 9 Upon initial power-on, the Ω function is chosen by default. The Models 3710 and 3730 will track AEMC Model 3710 down to 0.7 Ω and indicate below GROUND TESTER I N S T R U M E N T S 1 Ω...
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0.300 to 3.000 A 0.001 A (1 mA) 3.00 A to 30.00 A 0.01 A (10 mA) AEMC Model 3710 GROUND TESTER I N S T R U M E N T S HOLD Ω Figure 12 Ground Resistance Tester Models 3710/3730...
. The user has the option of having the alarm triggered when a reading is below the programmed setpoint. This is accomplished with an internal switch and outlined in the following section. Ground Resistance Tester Models 3710/3730...
Use caution not to pinch the battery leads. 6. Install and tighten screws. Alarm Setpoint Switch Right - Alarm above the setpoint Left - Alarm below the setpoint Battery Compartment Figure 15 Ground Resistance Tester Models 3710/3730...
(Fig. 18) along with four repetitive beeps and a fifth long tone. The memory is now cleared (Fig. 19). Once cleared, releasing the ON & MEM buttons returns the instrument to Resistance measurement mode. Ground Resistance Tester Models 3710/3730...
Function Setting Function Used Saved @ Power Down Memory On/Off ON + A Memory Recall (MR) ON + MEM (< 2 sec) Clear Memory ON + MEM (> 6 sec) Program Alarm ON + AL Setpoint Ground Resistance Tester Models 3710/3730...
Rx = 25.2 Ω In most field applications, the number of electrodes that make up a multi-grounded system would be higher, therefore the equivalent parallel resistance is negligible with respect to the rod under test. Ground Resistance Tester Models 3710/3730...
For future Ground Utility Ground level pole reference, note the date, ohms reading, current Butt plate reading and pole number. Replace any molding you Figure 22 may have removed from the conductor. Ground Resistance Tester Models 3710/3730...
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Service Meter Service meter Ground Level Ground level Ground Figure 23 Ground rods Rods Building Wall Building wall Pole-mounted Pole-mounted transformer Transformer Service Service box Service Meter Service meter Water pipe Water Pipe Figure 24 Ground Resistance Tester Models 3710/3730...
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Enclosure than one rod exists at different corners of the enclosure, it is neces- sary to determine how they are connected to Underground Underground service properly measure the Ground Ground Service Rods rods ground resistance. Ground Resistance Tester Models 3710/3730...
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The test is effective and accurate when the ground window is connected to the utility ground at only one point. Ground Resistance Tester Models 3710/3730...
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The Electric Utility Neutral should be the principle conductor of the low- impedance signal return path required to test the resistance of this ground electrode with the Model 3710/3730. This can be verified by removing other ground connections, noting if any changes appear in the readings.
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After noting the ground current, select the ground resistance range “Ω” and measure the resistance directly. The reading you measure with the 3710/3730 indicates the resistance of not just the rod, but also the con- nection to the sheath ground and all bonding connections between the sheath bond and the rod.
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5 Amps, resistance measurements are not possible. Do not proceed further with the measurement. Remove the clamp-on tester from the circuit, noting the location for attention, and continue to the next test location. Ground Resistance Tester Models 3710/3730...
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After noting the current, select the ground resistance range “Ω” and measure the resistance directly. The reading you measure with the 3710/3730 indicates the bonding connections between the Telephone ground and the Power company ground. One of the following two scenarios should be observed: A.
Operating Reference Card Included with the Model 3710 and 3730 you will find an operating refer- ence card like the one shown here. This card summarizes all the features of the Model 3710 and 3730. Clamp-on Ground AEMC Resistance Tester...
(Fig. 33). It is provided to perform a quick check of the instruments. Check the clamp-on ground resistance tester by clamping around the loop; the 3710 or 3730 should read between 24.2 Ω and 25.8 Ω. * Value is for ambient temperature between 68° and 78°F. Value may differ a few counts under or above this temperature.
A We are measuring the grounding network. The only requirements are that ground connections be made to the system under test and that the voltage-to-ground at the tested point not exceed the instrument rating. Ground Resistance Tester Models 3710/3730...
3. Remove back cover by pulling it down and away from the instrument. 4. Lift the battery away from the case and disconnect the battery. 5. Connect the new battery and position the leads so that they won’t get pinched when the cover is replaced. Ground Resistance Tester Models 3710/3730...
Deactivate Alarm or Change Setpoint Trigger mode Display is erratic Foreign matter in jaws Clean jaw mating surfaces Function controls inoperative Hold button on Turn HOLD off Light pulsing audible beep Normal operation Battery power management feature Ground Resistance Tester Models 3710/3730...
Repair and Calibration To guarantee that your instrument complies with the factory specifica- tions, we recommend that the Models 3710 & 3730 be submitted to our factory service center at one-year intervals for recalibration, or as required by other standards.
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Instruments Will Do: If a malfunction occurs within the 1 year period, you may return the Ground Resistance Testers Models 3710 & 3730 to us for repair or replacement free of charge, provided we have your REGISTRATION CARD on file. AEMC ®...
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