AEMC 6418 User manual

WITH AEMC
®
INSTRUMENTS
CLAMP-ON GROUND TESTER
Clamp-On
Ground Resistance Tester
Model 6418
ENGLISH
User Manual

Copyright©Chauvin Arnoux®, Inc. d.b.a. AEMC®Instruments. All rights reserved.
No part of this documentation may be reproduced in any form or by any means (including electronic
storage and retrieval or translation into any other language) without prior agreement and written consent
from Chauvin Arnoux®, Inc., as governed by United States and International copyright laws.
Chauvin Arnoux®, Inc. d.b.a. AEMC®Instruments
15 Faraday Drive • Dover, NH 03820 USA
Tel: [phone] or [phone] • Fax: [phone]
This documentation is provided as is, without warranty of any kind, express, implied, or otherwise.
Chauvin Arnoux®, Inc. has made every reasonable e󰀨ort to ensure that this documentation is accurate;
but does not warrant the accuracy or completeness of the text, graphics, or other information contained
in this documentation. Chauvin Arnoux®, Inc. shall not be liable for any damages, special, indirect,
incidental, or inconsequential; including (but not limited to) physical, emotional or monetary damages
due to lost revenues or lost prots that may result from the use of this documentation, whether or not the
user of the documentation has been advised of the possibility of such damages.

Chauvin Arnoux®, Inc.
d.b.a AEMC®Instruments
www.aemc.com
Statement of Compliance
Chauvin Arnoux®, Inc. d.b.a. AEMC® Instruments
certies that this instrument has been calibrated
using standards and instruments traceable to
international standards.
We guarantee that at the time of shipping your
instrument has met the instrument’s published
specications.
An NIST traceable certicate may be requested
at the time of purchase, or obtained by returning
the instrument to our repair and calibration
facility, for a nominal charge.
The recommended calibration interval for this
instrument is 12 months and begins on the date of
receipt by the customer. For recalibration, please
use our calibration services. Refer to our repair and
calibration section at www.aemc.com/calibration.
Serial #:
Catalog #: 2141.03
Model #: 6418
Please ll in the appropriate date as indicated:
Date Received:
Date Calibration Due:

TABLE OF CONTENTS
1. INTRODUCTION..................................................................6
1.1 INTERNATIONAL ELECTRICAL SYMBOLS ........................... 6
1.2 DEFINITION OF MEASUREMENT CATEGORIES (CAT) ...... 6
1.3 PRECAUTIONS FOR USE ........................................................ 7
1.4 RECEIVING YOUR SHIPMENT................................................ 8
1.5 ORDERING INFORMATION..................................................... 8
1.5.1 Accessories and Replacement Parts ................................. 8
2. PRODUCT FEATURES.......................................................9
2.1 DESCRIPTION ........................................................................... 9
2.2 FUNCTION KEYS .................................................................... 10
2.3 DISPL AY ................................................................................... 10
2.4 INSERTING BATTERIES ........................................................ 11
2.5 DATE AND TIME SETUP ........................................................ 11
3. OPERATION ...................................................................... 12
3.1 G E N E R A L ................................................................................. 12
3.2 IMPEDANCE AND CURRENT MEASUREMENT................. 12
3.2.1 Connection ....................................................................... 13
3.2.2 Freezing And/Or Storing A Measurement........................ 13
3.2.3 Auto-Hold Function .......................................................... 14
3.2.4 Alarms .............................................................................. 14
3.3 CURRENT MEASUREMENT.................................................. 14
3.4 CO NFIGUR ATI ON (SET-UP) .................................................. 15
3.5 ERRORS................................................................................... 17
3.6 AUTOMATIC STOP.................................................................. 18
3.7 STOR AGE................................................................................. 18
3.7.1 Recording A Measurement ............................................... 18
3.7.2 Viewing Recordings .......................................................... 19
3.7.3 Erasing All Recordings ..................................................... 19
3.7.4 Memory Full ...................................................................... 20
4. TECHNICAL CHARACTERISTICS ................................. 21
4.1 GENERAL REFERENCE CONDITIONS................................ 21
4.2 ELECTRICAL CHARACTERISTICS ...................................... 21
4.2.1 Impedance Measurements ............................................... 21
4.2.2 Current Measurements .................................................... 22
4.2.3 Storage............................................................................. 22

4.3 INFLUENCES........................................................................... 22
4.3.1 Impedance Measurement:................................................ 23
4.3.2 Current Measurement: ..................................................... 24
4.4 POWER SUPPLY ..................................................................... 24
4.5 ENVIRONMENTAL CONDITIONS ......................................... 25
4.6 MECHANICAL CHARACTERISTICS..................................... 25
4.7 COMPLIANCE WITH INTERNATIONAL STANDARDS ....... 26
4.8 ELECTROMAGNETIC COMPATIBILITY (EMC) ................... 26
5. MAINTENANCE ................................................................27
5.1 CLEANING................................................................................ 27
5.2 BATTERY REPLACEMENT .................................................... 27
5.3 REPAIR AND CALIBRATION ................................................. 29
5.4 TECHNICAL ASSISTANCE .................................................... 29
5.5 LIMITED WARRANTY............................................................. 30
5.5.1 WARRANTY REPAIRS ................................................30

6Clamp-On Ground Resistance Tester Model 6418 - User Manual
1. INTRODUCTION
Thank you for purchasing an AEMC®Instruments Clamp-On Ground
Resistance Tester Model 6418.
For the best results from your instrument and for your safety, you must read the
enclosed operating instructions carefully and comply with the precautions for use.
Only qualied and trained operators should use this product.
1.1 INTERNATIONAL ELECTRICAL SYMBOLS
Signies that the instrument is protected by double or reinforced insulation
CAUTION - Risk of Danger! Indicates a WARNING. Whenever this symbol
is present, the operator must refer to the user manual before operation
Indicates a risk of electric shock. The voltage at the parts marked with this
symbol may be dangerous
Application or withdrawal authorized on conductors carrying dangerous
voltages. Type A current sensor as per IEC 61010-2-032
Indicates Important information to acknowledge
This product complies with the Low Voltage & Electromagnetic Compatibility
European directives
The product has been declared recyclable
In the European Union, this product is subject to a separate collection
system for recycling electrical and electronic components in accordance with
directive WEEE 2012/19/EU
1.2 DEFINITION OF MEASUREMENT CATEGORIES (CAT)
CAT IV: Corresponds to measurements performed at the primary electrical
supply (< 1000 V).
Example: primary overcurrent protection devices, ripple control units,
and meters.
CAT III: Corresponds to measurements performed in the building installation
at the distribution level.
Example: hardwired equipment in xed installation and circuit
breakers.
CAT II: Corresponds to measurements performed on circuits directly
connected to the electrical distribution system.
Example: measurements on household appliances and portable tools.

Clamp-On Ground Resistance Tester Model 6418 - User Manual 7
1.3 PRECAUTIONS FOR USE
This instrument is compliant with safety standard IEC 61010-2-032, for voltages
up to 100 V in CAT IV or 150 V in CAT III. Failure to observe the safety instructions
may result in electric shock, re, explosion, and destruction of the instrument and
of the installations.
■The operator and/or the responsible authority must carefully read and clearly
understand the various precautions to be taken in use. The operator and/
or the responsible authority must carefully read and clearly understand
the various precautions to be taken in use. Sound knowledge and a keen
awareness of electrical hazards are essential when using this instrument.
■If you use this instrument other than as specied, the protection it provides
may be compromised, thereby endangering you.
■The safety of any system in which this instrument might be incorporated is the
responsibility of the integrator of the system.
■Do not use the clamp above its rated frequency, since this might cause it to
overheat dangerously.
■Do not use the instrument on networks of which the voltage or category
exceeds those mentioned.
■Observe the environmental conditions of use.
■Do not use the instrument if it seems to be damaged, incomplete, or poorly
closed.
■Before each use, check the condition of the insulation on the housing. Any
item of which the insulation is deteriorated (even partially) must be set aside
for repair or scrapping.
■Before using your instrument, check that it is perfectly dry. If it is wet, it must
be thoroughly dried before it can be connected or used.
■When handling the instrument, keep your ngers behind the physical guard.
■Avoid impacts on the measurement head, in particular the air gap.
■Keep the surfaces of the air gap clean; even a little dirt can cause the clamp
to malfunction.
■Use personal protection equipment systematically.
■All troubleshooting and metrological checks must be done by competent
accredited personnel.

8Clamp-On Ground Resistance Tester Model 6418 - User Manual
1.4 RECEIVING YOUR SHIPMENT
Upon receiving your shipment, make sure that the contents are consistent with
the packing list. Notify your distributor of any missing items. If the equipment
appears to be damaged, le a claim immediately with the carrier and notify your
distributor at once with a detailed description of any damage. Save the damaged
packing container to substantiate your claim.
1.5 ORDERING INFORMATION
Clamp-On Ground Resistance Tester Model 6418 ...................... Cat. #2141.03
Includes hard carrying case, 5 Ω calibration loop, four 1.5 V AA batteries, wrist
strap, Bluetooth adapter, multilingual safety sheet, Quick Start Guide, and USB
drive containing User Manual.
1.5.1 Accessories and Replacement Parts
Hard Carrying Case ......................................................................... Cat. #2141.52
5 Ω Calibration Loop ........................................................................ Cat. #2141.51
Order Accessories and Replacement Parts Directly Online
Check our Storefront at www.aemc.com/store for availability

Clamp-On Ground Resistance Tester Model 6418 - User Manual 9
2. PRODUCT FEATURES
2.1 DESCRIPTION
The simple-to-use Clamp-On Ground Tester Model 6418 makes ground
impedance measurements in a parallel earth network, such as power distribution
poles and overhead ground conductors. These measurements are simpler to
perform than traditional measurements with two auxiliary rods.
The Model 6418 can make accurate low value ground impedances
measurements and AC current measurements. The instrument's large oblong
measurement head can clamp around bars up to 1.18 x 1.57 in (30 x 40 mm).
The memory function records measurements for later viewing. Also, the
instrument’s OLED (Organic Light Emitting Diode) display screen is easy to read,
even in direct sunlight.

10 Clamp-On Ground Resistance Tester Model 6418 - User Manual
2.2 FUNCTION KEYS
As a general rule, functions shown in white on the keys are available when the
switch is set to Ω+A or A. The yellow arrow keys (▲, ▼ and ►) are available
when the switch is set to MR or SET-UP.
Key Function
Switch the display unit backlighting ON and OFF.
MEM Record the measurement displayed.
HOLD Freeze/unfreeze the display of the measurement.
▲
▼
Browse in:
SET-UP menu and change the value of the parameter
selected.
Memory read (MR).
►When switch is set to:
Ω+A or A: a long press on ► activates/deactivates the
audible signal.
SET-UP: ► browses in the menu and conrms the changes
made.
MR: ► toggles the display between the measurement and
the date/time.
2.3 DISPLAY
When the measurement exceeds the limits of the measurement range, the
instrument displays OR.

Clamp-On Ground Resistance Tester Model 6418 - User Manual 11
2.4 INSERTING BATTERIES
Refer to § 5.2.
2.5 DATE AND TIME SETUP
The rst time you turn ON the instrument by turning the switch to Ω+A, the
instrument prompts you to set the date.
The year blinks, indicating it can be
edited. Set it using the ▲ and ▼ keys.
Then press the ► key; the month
blinks. Set it using ▲ and ▼.
Press ►. The date blinks; set it using
▲ and ▼ and conrm by pressing ►.
The instrument then displays the
time format. Choose 24 h or
12 h (A or P) using ▲ and ▼.
Conrm by pressing ►. The hours
reading blinks. Set it using ▲ and ▼
and conrm by pressing ►.
The minutes reading blinks. Set it
using ▲ and ▼ and conrm with ►.

12 Clamp-On Ground Resistance Tester Model 6418 - User Manual
3. OPERATION
3.1 GENERAL
When turned ON, the instrument performs self-calibration. The jaws of the clamp
must therefore be closed and not clamped around any conductor.
If the instrument fails to complete self-calibration, the error message Err. CAL is
displayed. If this happens, turn the instrument OFF and ensure the air gaps are
clean. Then turn the instrument ON.
3.2 IMPEDANCE AND CURRENT MEASUREMENT
Set the switch
to Ω+A.
Press the trigger to open the jaws,
and clamp around the conductor
that is part of the ground system to
be measured.
When the jaws are open, the
symbol is displayed and the
instrument cannot make a mea-
surement.

Clamp-On Ground Resistance Tester Model 6418 - User Manual 13
3.2.1 Connection
The ground electrode to be measured (RX) is in a series/parallel arrangement
with other ground electrodes via the earth impedance (ZE) and physical
connection to other resistance paths (ZS). The measured impedance will be
slightly greater than RXassuming the downstream impedance is very low. For
example: If RX is 21 Ω and ZS/R1-Rn is e󰀨ectively 0.6 Ω, the Model 6418
will read 21.6 Ω.
NOTE: During the impedance measurement, the instrument emits
an intermittent audible beeping signal. This is caused by the
measurement frequency that ows in the measurement head. The
sound can vary as a function of the frequency and amplitude of the
current measured. This sound is normal and cannot be eliminated.
3.2.2 Freezing And/Or Storing A Measurement
When the measurement has stabilized, you can press the HOLD key to freeze
the measurement and/or MEM to record the measurement.

14 Clamp-On Ground Resistance Tester Model 6418 - User Manual
3.2.3 Auto-Hold Function
The AUTO-HOLD function (see § 3.4), freezes the measurement automatically
when the jaws of the clamp are opened. This can be useful when you have only
one hand free to make a measurement.
3.2.4 Alarms
To facilitate making measurements, you can program an alarm on the impedance
measurement (see § 3.4) and/or the current measurement (see § 3.4). You can
then be aware whether the measurement is acceptable without looking at
the display.
The alarm indicator on the
display blinks and the instrument
emits a continuous audible
signal.
To eliminate the audible signal,
press and hold the ► key.
If you set alarms on both the
impedance and the current,
and both alarm thresholds are
exceeded, the alarm on the
current has priority.
3.3 CURRENT MEASUREMENT
The current measurement alone is identical to the current measurement with the
impedance measurement.
Set the switch
to A.
PRESS the trigger to open the jaws of the clamp and clamp
the conductor in which the current to be measured ows.

Clamp-On Ground Resistance Tester Model 6418 - User Manual 15
When the measurement has stabilized, you can press the HOLD key to freeze it
and/or MEM to record it in memory. You can also use the AUTO-HOLD function
(see § 3.4) to freeze the measurement automatically when the clamp jaws
are opened. This can be useful when you have only one hand free to make a
measurement. To facilitate making measurements, you can congure an alarm
on the current measurement value (see § 3.4).
3.4 CONFIGURATION (SET-UP)
Set the switch to SET-UP.
Use the ▼ and ▲ keys to scroll through the screens of the SET-UP menu.
CLR (erase memory) menu.
PRESS the ► key to enter the CLR menu.
To cancel, PRESS ►.
To erase all records, PRESS and HOLD the ▲ and ▼
keys simultaneously. The instrument emits 5 audible
beeps before erasing the memory.
SND menu (activation of the sound).
PRESS ► to enter the SND menu. Use ▲ and ▼ to
display or hide the symbol.
When is displayed, the instrument emits an
audible signal when keys are pressed and when alarm
thresholds are crossed.
Conrm by PRESSING ►.
During the measurements (when the switch is set to
Ω+A or A), a long press on ► activates/deactivates
the audible signal.
STOP menu (automatic standby).
PRESS ► to enter the STOP menu. Use ▲ and
▼ to display or hide the symbol (permanent
operation).
When is displayed, automatic switching of the
instrument to standby at the end of 5 minutes is
disabled. Conrm by PRESSING ►.

16 Clamp-On Ground Resistance Tester Model 6418 - User Manual
ALΩ menu (impedance alarm).
PRESS ► to enter the ALΩ menu. Use ▲ and ▼ to
scroll through the display:
: no impedance alarm.
: : impedance alarm activates when
impedance > 10 Ω.
: impedance alarm activates when
impedance < 10 Ω.
PRESS ►; the alarm threshold blinks. Set it using ▲
and ▼.
Acceptable values are between (1 and 199) Ω.
A long press scrolls the values faster.
Conrm by PRESSING ►.
AL A menu (current alarm).
PRESS ► to enter the AL A menu. Use ▲ and ▼ to
scroll through the display:
: no current measurement alarm.
: current alarm activates when
current > 30 mA.
PRESS ►; the alarm threshold blink. Set it using ▲
and ▼. Acceptable values are between
(1 mA and 20.0 A). A long press scrolls the values
faster.
PRESS ► to conrm.
DATE menu (setting of the date).
PRESS ► to enter the DATE menu. Use ▲ and ▼ to
set the year. PRESS ►; the month setting blinks.
Set it using ▲ and ▼.
Do the same for the day setting and conrm with the
► key.
For a more detailed procedure, see § 2.5.
HOUR menu (setting of the time).
PRESS ► to enter the HOUR menu. Use ▲ and ▼to
choose 24 h or 12 h (A or P) form. PRESS ►; the
hours setting blinks. Set this using ▲ and ▼.
PRESS ►; the minutes setting blinks. Set this using
▲ and ▼; conrm by PRESSING ►.
For a more detailed procedure, see § 2.5.

Clamp-On Ground Resistance Tester Model 6418 - User Manual 17
HOLD menu (activation of the AUTO-HOLD
function).
PRESS ► to enter the AUTO-HOLD menu. Use ▲
and ▼ to display or hide the symbol. When
this symbol is displayed, the AUTO-HOLD function
is activated. In this mode, when the measurement is
stable, it is frozen when the clamp is opened.
Conrm by PRESSING ►.
VER menu (display of the software version).
PRESS ► to display the software version number.
PRESS ▼ to display the instrument serial number.
CAL menu (not used)
3.5 ERRORS
During the measurement, the instrument reports any errors.
Display of the NOISE symbol during the impedance
measurement indicates that the current (> 5 A) or
voltage (ZxI > 25 V) is too high, making the accuracy
of the displayed measurement uncertain.
When the current exceeds 10 A, the impedance
measurement is not displayed (dashes appear in the
measurement eld).

18 Clamp-On Ground Resistance Tester Model 6418 - User Manual
When the impedance measurement is > 1200 Ω, the
instrument displays OR.
When the current measurement is > 20 A, the
instrument so indicates.
When the impedance measurement is < 1 Ω, the
display alternately indicates the measured value and
LOOP, indicating the value is very low for a valid
ground impedance measurement and most likely
indicates the measurement is through a wire loop
rather than through the earth.
3.6 AUTOMATIC STOP
After 5 minutes of inactivity, the instrument enters to standby mode. Press any
key or turn the switch to any setting to exit standby. The instrument restarts
without repeating the calibration procedure if it has not been on standby for more
than 15 minutes. It is possible to disable automatic standby; refer to § 3.4 (STOP
menu). The symbol is then displayed.
3.7 STORAGE
3.7.1 Recording A Measurement
To record a measurement, PRESS the MEM key.
You can rst PRESS the HOLD key to freeze the measurement.

Clamp-On Ground Resistance Tester Model 6418 - User Manual 19
NOTE: To record a measurement, the batteries must not be
discharged (the symbol must not be displayed).
The measurement is recorded in the
memory slot of which the number
is displayed (in this example, slot
number 2).
It is recorded with all accompanying
information:
date and time
any alarms and their status
(triggered or not)
any errors (NOISE, OR, LOOP)
ancillary displays (HOLD, )
3.7.2 Viewing Recordings
Set the switch
to MR.
The instrument displays the last measurement recorded.
PRESS ► to display the date and time.
Use ▲ and ▼ to scroll through all of the recorded measurements.
3.7.3 Erasing All Recordings
Set the switch to SET-UP.,
then follow the procedure
described in § 3.4 in the
CLR menu.
When you return to the
MR setting, the instrument
indicates that the memory
is empty.

20 Clamp-On Ground Resistance Tester Model 6418 - User Manual
3.7.4 Memory Full
You can record up to 300 measurements (numbered from 0 to 299).
If you continue recording, measurement number 300 overwrites measurement
number 0, measurement 301 overwrites measurement 1, and so on.
The instrument reports this by alternately displaying FULL and the memory slot
number.
You can continue in this way up to number 9999, at which point recording
becomes disabled and you must erase the memory to be able to resume
recording.