Megger NIM 1000 User Manual

NIM 1000

Net Impedance Meter

USER GUIDE

Issue: 04 (06/2016) - EN
Article number: 82941

1

2

Consultation with Megger

Consultation with Megger

The present system manual has been designed as an operating guide and for
reference. It is meant to answer your questions and solve your problems in as fast and
easy a way as possible. Please start with referring to this manual should any trouble
occur.

In doing so, make use of the table of contents and read the relevant paragraph with
great attention. Furthermore, check all terminals and connections of the instruments
involved.

Should any question remain unanswered or should you need the help of an authorized
service station, please contact:

Megger Limited Seba Dynatronic

Mess- und Ortungstechnik GmbH

Archcliffe Road
Kent CT17 9EN

T: [phone]
F: [phone]
E: [e-mail]

Hagenuk KMT
Kabelmesstechnik GmbH

Röderaue 41
D - 01471 Radeburg / Dresden

T: [phone] – 0
F: [phone]
E: [e-mail]

Dr.-Herbert-Iann-Str. 6
D - 96148 Baunach

T: [phone] – 0
F: [phone]
E: [e-mail]

Megger USA

Valley Forge Corporate Centre
2621 Van Buren Avenue
Norristown, PA 19403 USA

T: [phone]
F: [phone]

 Megger

All rights reserved. No part of this handbook may be copied by photographic or other means unless Megger
have before-hand declared their consent in writing. The content of this handbook is subject to change without
notice. Megger cannot be made liable for technical or printing errors or shortcomings of this handbook.
Megger also disclaims all responsibility for damage resulting directly or indirectly from the delivery, supply, or
use of this matter.

3

Terms of Warranty

Terms of Warranty

Megger accept responsibility for a claim under warranty brought forward by a customer
for a product sold by Megger under the terms stated below.

Megger warrant that at the time of delivery Megger products are free from manufacturing
or material defects which might considerably reduce their value or usability. This
warranty does not apply to faults in the software supplied. During the period of warranty,
Megger agree to repair faulty parts or replace them with new parts or parts as new (with
the same usability and life as new parts) according to their choice.

This warranty does not cover wear parts, lamps, fuses, batteries and accumulators.

Megger reject all further claims under warranty, in particular those from consequential
damage. Each component and product replaced in accordance with this warranty
becomes the property of Megger.

All warranty claims versus Megger are hereby limited to a period of 12 months from the
date of delivery. Each component supplied by Megger within the context of warranty will
also be covered by this warranty for the remaining period of time but for 90 days at
least.

Each measure to remedy a claim under warranty shall exclusively be carried out by
Megger or an authorized service station.

This warranty does not apply to any fault or damage caused by exposing a product to
conditions not in accordance with this specification, by storing, transporting, or using it
improperly, or having it serviced or installed by a workshop not authorized by Megger.
All responsibility is disclaimed for damage due to wear, will of God, or connection to
foreign components.

For damage resulting from a violation of their duty to repair or re-supply items, Megger
can be made liable only in case of severe negligence or intention. Any liability for slight
negligence is disclaimed.

Since some states do not allow the exclusion or limitation of an implied warranty or of
consequential damage, the limitations of liability described above perhaps may not
apply to you.

4

Contents

Contents

Consultation with Megger ............................................................................................... 3

Terms of Warranty ........................................................................................................... 4

Contents ........................................................................................................................... 5

1 Basic Notes ....................................................................................................... 7

2 Technical Description ...................................................................................... 9

2.1 System Description ............................................................................................ 9

2.2 Technical Data ................................................................................................. 11

2.3 Connections, Controls and Display .................................................................. 12

3 Electrical connection ..................................................................................... 13

4 Operation ........................................................................................................ 16

4.1 System Settings ............................................................................................... 18

4.2 Performing Measurements ............................................................................... 19

4.2.1 Network Impedance Measurement .................................................................. 20

4.2.1.1 Prepare Measurement ...................................................................................... 20

4.2.1.2 Performing the Measurement ........................................................................... 22

4.2.1.3 Analysing Measurement Results ...................................................................... 23

4.2.2 Measuring in Fault Mode .................................................................................. 25

4.2.2.1 Preparing Measurement ................................................................................... 25

4.2.2.2 Performing the Measurement ........................................................................... 26

4.2.2.3 Identifying and Locating Faults ........................................................................ 27

4.3 Exporting the Measured Data .......................................................................... 28

5 Maintenance and care .................................................................................... 29

Annex 1: Measuring Accuracy ..................................................................................... 30

Annex 2: Measuring Range ........................................................................................... 32

5

Basic Notes

Labelling of safety

Working with products

1 Basic Notes

Safety precautions

instructions

from Megger

This handbook contains basic instructions for the initial use and operation of the NIM

1000. For this reason, it is important to ensure that the manual is always available to
authorised and trained personnel. Operating personnel should read the manual
thoroughly. The manufacturer will not be held liable for any injury or damage to
personnel or property through failure to observe the safety precautions contained in this
handbook.

The specific standards and regulations in each country must also be observed.

Important instructions concerning personnel, operational and technical safety are
marked in the text as follows:

Symbol Description

Indicates a potential danger of an electric shock that may result in fatal or
serious injury.

WARNING

CAUTION

It is important to observe the general electrical regulations of the country in which the
device will be installed and operated, as well as the current national accident prevention
regulations and internal company directives (work, operating and safety regulations).

Indicates a potential danger that may lead to slight or moderate injury.

The notes contain important information and useful tips for using the
system. Failure to observe them can render the measurement results
useless.

Operating staff

Declaration of

Conformity (CE)

Use genuine accessories to ensure system safety and reliable operation. The use of
other parts is not permitted and invalidates the warranty.

This system and its peripheral equipment may only be operated by trained or instructed
personnel. Anyone else must be kept away.

The system may only be installed by an authorised electrician. DIN VDE 0104 (EN

50191), DIN VDE 0105 (EN 50110) and the German accident prevention regulations
(UVV) define an electrician as someone whose knowledge, experience and familiarity
with the applicable regulations enables him to recognise potential hazards.

The product meets the following security requirements of the European Council
Directives:

• EMC Directive (2004/108/EC)

• Low Voltage Directive (2006/95/EC)

• RoHS Directive (2011/65/EU)

7

Basic Notes

Radiated emission

The device is intended for operation in the industrial segment in accordance with EN

55011. When used at home it could cause interference with other equipment (such as
the radio or television).

The interference level from the line complies with the limit curve B (living area), the
radiation level complies with the limit curve A (industrial area). Once the living area is
sufficiently far away from the planned area of operation (industrial area), equipment
there will not be impaired.

Use only as intended

Procedure in the event

that the device

malfunctions

The operating safety is only guaranteed if the delivered system is used as intended.
Incorrect use may result in danger to the operator, to the system and the connected
equipment.

The thresholds listed in the technical data may not be exceeded under any
circumstances. Condensation during the operation of Megger products may result in
danger to persons and devices through voltage arc-over. Prevent condensation before
and during the measuring mode by cooling the measuring systems sufficiently. The
operation of Megger products in direct contact with water, aggressive substances and
inflammatory gases and vapours is prohibited.

The NIM 1000 is built to be robust and can withstand the stresses it can expect to be
subjected to in demanding everyday use. Nevertheless, it is a precision measuring
device which needs to be treated with the appropriate care. This applies in particular to
the connection cable and the clamps, which play an important role in ensuring the
device remains safe while the results of measurements remain precise.

The system may only be operated whilst it is in perfect working condition. In the event of
damage, irregularities or malfunctions that cannot be resolved with the assistance of the
operating instructions, the system must be shut down immediately and labelled
accordingly. In such an event, the relevant management must be informed. Please
contact Megger Service immediately to eliminate the malfunction. The system may only
be started up again once the malfunction has been eliminated.

8

Technical Description

Intended use

Function

2 Technical Description

2.1 System Description

The NIM 1000 serves to measure network impedance in low voltage grids. In this
process, the conductor connections are tested for their current carrying capacity while
subjected to typical operating loads and potential flaws are indicated.

With the help of the following range of preventative applications, a consistently good
supply quality can be guaranteed, outages prevented and adequate network rating
ensured:

• Preventative inspection and uncovering of faults (e.g. neutral conductor fault)

• Determination of the maximum connected / feed-in power

• Monitoring for secure shut-down (rating of fuses)

• Approval of new / modified network sections

Fault detection in low voltage grids is another area of application of the device. For
example, the NIM 1000 can be used to trigger a load-dependent fault which can then be
located either with the help of a simultaneously connected measuring device or by
means of multiple measurements at various connection points.

The device is linked to the low voltage grid to be tested by means of the available
connection cables (four-conductor measurement with Kelvin clips) and also receives its
supply voltage over these wires.

In preparation for a measurement, either a defined measurement period or a target
number of measurements can be specified.

To determine the network impedance, the adjustable load current is generated for a
short period by means of a semi-conductor circuit-breaker with the appropriate load­resistor. The current and voltage curves are recorded immediately before and while
applying the load by means of A/D converters and then analysed by calculation. The
result is shown on the display.

When taking measurements on more than one phase, there is automatic switching
between the phases.

9

Technical Description

Features

Scope of delivery

Check contents

The NIM 1000 combines the following features in one device:

• Compact and sturdy design for portable use in the field

• Easy and convenient operation via rotary encoder

• Single and three phase measurement

• High test current of up to 1000 A

• Network impedance measurement (resistance and reactance) up to the

10th harmonic

• Automatic detection of rotary field

• Logging (export via USB interface)

• Wide range input for the voltage supply

The scope of delivery of the system includes the following:

Quantity Component Description Item number

1 Basic device 128312147

Optional accessories

4 High performance

Kelvin clamp

2 Connection lead brown 90009320

2 Connection lead black 90009321

2 Connection lead grey 90009322

2 Connection lead blue 90009323

1 NIM 1000-A socket

adapter

1 USB flash drive 890020928

10 Spare fuses T 25A H 440V (6.3 mm x 32 mm) 90004745

1 Manual 82941

Check the contents of the package for completeness and visible damage right after
receipt. In the case of visible damage, the device must under no circumstances be taken
into operation. If something is missing or damaged, please contact your local sales
representative.

If the following optional accessories do not form part of the scope of delivery, these can
be ordered from sales:

Accessory Description Item number

PKC-1 90009319

128311627

Kelvin clip with
connection cable

Smaller clip ideally suited for use when space
is restricted.

10

138315892

Technical Description

2.2 Technical Data

The NIM 1000 is defined by the following technical parameters:

Parameter Value

Test current

• Range 80 A … 1000 A (adjustable)

• Maximum current as a peak value

depends on the network

(I

max

impedance and the temperature and
is, under certain circumstances,

≤1000 A at 400 V
≤600 A at 230 V
≤300 A at 115 V

significantly lower than the indicated
values)

Input voltage

(supply voltage at the same time)

100 V ... 480 V, 50/60 Hz
(at test terminals)

100 V … 230 V, 50/60 Hz
(at Schuko socket)

Operating uncertainty B (in accordance

Up to 3% ±1 mΩ (see also Annex 1)

with IEC 61557-3)

Measuring range

10 mΩ … 5 Ω (230 V / 400 V)
10 mΩ … 2,5 Ω (115 V)

(See also Annex 2)

Resolution

Measurement category

1 mΩ

300V CAT IV or
600V CAT IV (when using the PKC-1 high

performance connection clamps)

Safety functions

Display

Memory

Interfaces

Operating temperature

Operating humidity

Storage temperature

Weight

Dimensions

Protection class (in accordance with
IEC 61140 (DIN VDE 0140-1))

Ingress protection rating (in accordance

with IEC 60529 (DIN VDE 0470-1))

Temperature monitoring

Transflective sunlight readable 5.7" colour
display with a resolution of 640 x 480 pixels

At least 1000 records of test data

USB 2.0

-20°C to 55°C

Max. relative humidity 93% at 30°C

-30°C to 70°C

10 kg

410 x 175 x 335 mm

II

IP 50 (open)
IP 54 (closed)

11

Technical Description

2.3 Connections, Controls and Display

The NIM 1000 has the following connection, display and control elements:

Element Description

Display

Rotary encoder

USB port

Connection cables

Trigger output

12

Electrical connection

3 Electrical connection

Work on live equipment

The work can only be carried out safely while guaranteeing the protection
of the health of all those involved in the work by employing suitable
working procedures and using suitable protective equipment. For that
reason, the electrical connection of the device must absolutely conform to
the nationally applicable regulations for work on live equipment!

Connection sequence

When connecting the device, the two blue connection cables should be
connected to the neutral conductor of the low voltage cable first. Not until
after that can the live phase conductors be connected. The conductors are
disconnected in reverse order: first disconnect the phase conductors, then
the neutral conductor.

Connection diagram

WARNING

WARNING

The following figure shows the simplified connection diagram for the NIM 1000:

The fused measurement cables are colour-coded (brown = L1,

black = L2, grey = L3, blue = N).

Only a measurement cable with a matching colourcode may ever be

CAUTION

connected to one and the same Kelvin clip!

13

Notes

Specific connection-

Connection to IT

configurations

Electrical connection

When making electrical connections, the following points should be observed:

• When connected with the supplied PKC-1 high performance connection clamps,
the NIM 1000 is approved for measurements on low voltage installations in the
measurement category 600V CAT IV in accordance with IEC 61010-1.

• The input voltage live on the measurement cables serves simultaneously as
supply voltage and must remain within the range of 100 V and 480 V.

• The NIM 1000 must be connected to the neutral conductor and at least one
phase. If the neutral conductor is not accessible, the blue connection cable must
be connected to a free phase conductor.

• The connection should be made based on the principle of four-conductor
measurement. So two measurement cables (current and voltage) must be
connected to each conductor intended to be measured using a Kelvin clip.

Using the NIM 1000, measurements can be carried out in both single-conductor mode
(just L1–N) as well as in multi-conductor mode (all possible conductor combinations).

Measurements are only carried out on phases which are live with a suitable input
voltage. Accordingly, phases which have not been connected will not be taken into
account in multiple-conductor mode.

So, for special applications or for time-saving reasons, the conductor combinations to be
measured can be purposefully limited in the multiple-conductor mode by using a specific
connection configuration. The following table shows some examples of this:

networks

Required
measurements

L2–N N (blue)

L1–L2 N (blue)

L2–L3
L2–N

Measurements can also be carried out on IT networks using the NIM 1000.

Given the lack of a neutral conductor, in measurements on networks of this kind it is
recommended that the blue test lead be connected to a free phase.

If, however, all phases are assigned test leads in multi-conductor mode, it is advisable
that the blue test lead be connected to the station earth or, in the case of an emergency,
even an earthing spike, in order to avoid faults in the voltage- and frequency detection
(otherwise the measurement will not start).

Phases to be
connected

L2 (black)

L1 (brown)
L2 (black)

N (blue)
L2 (black)
L3 (grey)

Measured conductor pairs

(instead of the 6 possible
combinations)

L2–N

L1–N
L2–N
L1–L2

L2–N
L3–N
L2–L3

14

Electrical connection

Connection to mains

Using the included NIM 1000-A adapter, the NIM 1000 can be quickly and safely

socket

connected to a mains socket for the purposes of measurement or the export of
measurement data. The plug is designed as a Schuko plug (CEE 7/4) but it can also be
connected to sockets of different designs without problem using the appropriate
accessories.

The connection between the NIM 1000 and the adapter should be established as follows
with the help of the blue and the brown connection cables:

15

Operation

System status

4 Operation

Power on

As soon as one of the three connection cables has been connected to a low voltage
phase with sufficient supply voltage (100 V ... 480 V), the NIM 1000 automatically turns
on.

After the short switching on process, the system waits for confirmation from the user that
the electrical connection has been finished.

The corresponding dialogue window can be shut by a quick push of the rotary
encoder , following which the three phase voltages are measured (audible phase

relay switching).

After switching on, the following information on the current status of the system is shown
on the left side of the display:

Connected phases which are taken

into account in a measurement in

3-conductor mode.

Set measuring current

Network voltage and frequency

currently measured

Selected measuring mode (number of

measurements or measurement
duration) and selected operating

mode

16

Operation

Operating concept

If it has been possible to detect the rotary field’s direction of rotation, this will be
indicated by the colour in which the phase designations are displayed:

Counter-clockwise rotary field

Clockwise rotary field

If, however, it is not possible to determine the direction of rotation say, for example,
because less than three phases have been connected or because one phase has
accidentally been connected multiple times, the phases are displayed in a black font.

Navigation within the menus is effected almost entirely from the circular selection menu:

Currently selected
menu item

Description of the
currently selected
menu item

System

Operating the system with the rotary encoder is as follows:

• Select the menu item

• Increase or decrease the value of a variable parameter

• Select an option from a selection list

• Call up the selected menu item

• Confirm the setting or the selection made

Each menu (with the exception of the main menu) has a menu item with which one
can return to the next higher menu level.

17

Operation

4.1 System Settings

Selecting the menu item takes you directly to the system menu, where the following
functions and submenus are available:

Menu

item

Description

Submenu with detailed system information

Information on the current versions of the various software
components

Hardware information (e.g. serial number of the system)

System settings

Setting the interface language.
Select the desired language by turning the rotary encoder and activate

by pressing it. The language selection is immediately active.

In this submenu, the brightness and layout of the display can be
adjusted and the background lighting can be switched on or off.

Setting the date and time.
The value of each segment that has been marked for selection can be

adjusted by turning the rotary encoder. Pressing causes the mark to
move the next segment.

Once the input has been concluded, the changes can either be
accepted with OK or rejected by selecting Cancel.

When this function is used, a search in respect of firmware and language files
is conducted in the directory nig/updates/ on the inserted USB flash drive.

The files found are then listed and, using the rotary encoder, these can be
selected and imported. A distinction is made between the following file types:

application-x.xx.img

nig-xxx.tar

nig-Languages.tar

An also possible update of the real-time software of the measuring
hardware needs not be initiated via this menu item. Instead of this, it
suffices to insert the USB flash drive with the update files into the USB
port and confirm the following query.

Updating solely an application to version x.xx

Importing the language xxx

Importing all the languages contained in the
language file

18

Operation

4.2 Performing Measurements

Selecting the operating

mode

By selecting the menu item in the main menu you will reach a sub menu in which
you may select your desired operating mode. In principle, measurements may be carried
out either in normal network impedance measuring mode or in fault detection mode.

Normal network impedance measuring takes place with a constant measuring current
and over a freely-adjustable duration or number of measurements. Only in this mode
can the software carry out a load calculation (see page 7) on the basis of the measured
network impedance. However, the suitability of this mode to detect faults is limited, as
some faults subside temporarily with higher current flows (e.g. due to fusing or drying
out). Depending on the level of the measuring current selected, this could already
happen during calibration and so the fault would remain undetected through the
measurement.

That is why fault mode has been integrated. In this mode, the load current is gradually
increased over the course of 8 measurements up to the preset value. All 8 recorded
curves are displayed together in one diagram, whereby the relevant changes can be
easily identified.

Further sub-division into single and multiple conductor mode gives the following
operating modes:

Menu

Description

item

Network impedance measurement on one conductor
The impedance is only measured on the phase which is connected via the brown

connection cables (L1).
This time-saving single-conductor mode is particularly suitable if the results of

one phase suffice for the intended purpose of the measurement or if only single­phase measuring is possible anyway (e.g. at sockets).

Network impedance measurement on up to 6 conductor combinations
In this mode, all possible conductor combinations (see page 14) are measured

one after the other depending on the connection situation.

Fault mode on one conductor
This serves to trigger a known load-dependent fault on the phase connected to

the brown connection cables (L1).
This mode is recommended if the conspicuous phase has already been

identified.

Fault mode on up to three conductors
In this mode the 8 measurements are carried out on all connected phases

(against the neutral conductor).
So conclusions on the characteristic of the fault can be drawn from load-

dependent impedance changes as well as from the comparison of the phases
with one another.

19

Operation

Setting the

4.2.1 Network Impedance Measurement

4.2.1.1 Prepare Measurement

measurement

parameters

By selecting the menu item in the main menu you will reach a sub menu in which
you may select the following measurement parameters in preparation for a network
impedance measurement.

Menu

item

Description

Maximum measuring current (80 ... 1000 A)
Because the accuracy of the measurement increases with increasing

measuring current, as high as possible a measuring current but also one which
is appropriate to the capacity of the network should be selected.

If the NIM 1000 is connected to a mains socket (with fusing of up to
16 A), the 80 A setting which has been particularly dimensioned for
this type of application should be selected!

Total measurement duration (0 … 20 days) and interval of the individual
measurements.

Over the whole measurement duration, one measurement per involved phase
is taken at the set interval.

After the menu item is selected, the two values are to be defined one after
another. The options for setting the interval depend on the previously set total
measurement time.

The number of measurements can also be defined as an alternative to
measurement duration (see below). The respective last adopted setting
applies.

Number of measurements (1 … 255)
The set number of measurements is carried out in quick succession and while

constantly switching between the phases involved.
The measurement duration can also be defined as an alternative to the

number of measurements (see above). The respective last adopted setting
applies.

Delay time (0 … 30 seconds)
The start of the measurement can be delayed by the time set here.

Resetting calibration values
If the time of calibration was quite a while ago (e.g. after a measurement which

lasted a while or in the case of temporary failure of a phase), it could be useful
to reset the calibration values.

Value to be calculated using a load calculation (see information on next page
too)

V

DIP

P

MAX

Off

Voltage dip at given connection power

Max. connection power at given voltage dip

Load calculation deactivated

20

Operation

Explanations

When it comes to the load calculation, the NIM 1000 utilises the following physical

concerning the load

calculation

correlation between the measurements for short-circuit power P
output P

and the anticipated voltage dip V

MAX

DIP

:

, the maximum rated

K

Z / PK

U

P

MAX

(1 – V

) ∙ U

DIP

Measurement

Analysis (load calculation)









 



+







= 0

Now, depending on the application scenario, only one of the two unknown variables
need be given in order to calculate the other:

Application scenario Procedure

A large consumer with a known load (P
connected to the measurement point and the
anticipated voltage dip (in %) calculated.

The aim is to calculate the maximum load which can be
connected to the measurement point without any
voltage dip defined by existing guidelines being
exceeded.

) should be

MAX

Call up the menu item and
select the option V

. Then

DIP

enter the load of the appliance.

Call up the menu item and
select the option P

MAX

. Then
enter the maximum permissible
voltage dip.

This function can also be used to calculate the
maximum feed-in load (e.g. of a PV
installation). Accordingly, in this case it is the
maximum permissible mains voltage increase
instead of the voltage dip which must be
specified.

21

Operation

Performing the

4.2.1.2 Performing the Measurement

Start measurement

measurement

Once all the settings have been carried out and checked, the measurement can be
started with the menu item .

If this is the first measurement after switching on the device or if the calibration values
were reset before the measurement (see previous page), calibration will be carried out
right after the start in order to set the preset maximum measuring current. A
corresponding notice will appear on the display.

Depending on the settings, the individual measurements will take place either in quick
succession (depending on the measuring current 2 to 10 seconds) or at 15 minute
intervals, switching between the involved phases.

The following measured values are shown on the display and continually updated during
the running measuring process as standard.

Frequency-based resistance curve

red = current measurement

green = average

Short circuit

current and

power

Frequency-based reactance curve

red = current measurement

green = average

Actual measuring

current

Ending the

measurement

Number of measurements already

carried out or already expired

measurement duration

Using the menu item during and after the measurement, the diagram types may be
switched between as follows:

R/X

|Z|/Phi

U/I

The measurement will end automatically as soon as the preset number of
measurements or the preset measurement time has been reached. The measurement

can be manually deactivated at any time via the menu item.

Impedance resistance and reactance

Impedance amount and phase shift angle

Current and voltage curve of the period in which the measurement took place

Current resistance and reactance

measured values at mains frequency and

at their 3rd and 9th harmonic

22

Operation

Result of the load

4.2.1.3 Analysing Measurement Results

Interpretation of the

curves

Toggling the phases

The red curve is hidden on completion of the measurement. Instead, dark-green
envelope curves are marked above and underneath the light-green medium value curve,
these envelope curves represent the upper and lower limit of 99.7% of the measured
values.

To be able to carry out a comparison between the measured conductor combinations in
the case of measuring more than one conductor, the following selection menu must be
called up via the menu item:

calculation

The conductor combination to be displayed is selected by turning the rotary encoder. By
changing the selection, the corresponding curves and measured values are displayed.

In addition to the typical measured values (see previous page), the results of a load
calculation (see page 20) which may have been carried out can be read on the left part
of the display:

Result of the load calculation

Physical value to be calculated

@ set requirement

23

Operation

Impedance of the PEN

In the case of measuring more than one conductor, there is another option named PEN

conductor

available for selection.

When this option is selected, the calculated impedance of the PEN conductor and the
following values for a three-phase short-circuit (calculated in accordance with
IEC 60909-0) are displayed:

Three-phase peak short-circuit current

Three-phase sustained short-circuit current

Three-phase sustained short-circuit power

Depending on the type of network and earthing conditions, these values do not
necessarily match those of the neutral conductor!

For instance, in the case of a three-phase measurement on IT networks, the
three-phase short circuit current and the three-phase short circuit power are also
measured. However, no impedance values (incl. graphs) will be shown for the
non-existent PEN conductor.

24

Operation

Setting maximum

Connecting the trigger

4.2.2 Measuring in Fault Mode

4.2.2.1 Preparing Measurement

measuring current

output to a

reflectometer

By selecting the menu item in the main menu you will reach a sub menu in which
you may preset the maximum measuring current via the menu item.

In fault mode, the current is increased as linearly as possible over 8 measurements up
to the set maximum value in this case.

If the NIM 1000 is connected to a mains socket (with fusing of up to 16 A), the
80 A setting which has been particularly dimensioned for this type of application
should be selected!

In the case of intermittent faults in particular, it is recommended that you carry out a fault
location at the same time as the fault trips. For this purpose, a suitable reflectometer
must be connected to the same low voltage cable and hooked up to the NIM 1000 via

the trigger output .

The triggering of the reflectometer takes place at the time of each respective impedance
measurement by means of a short 12 V voltage pulse at the trigger output.

For more details about commissioning and configuring the reflectometer,
please read the accompanying instructions.

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Operation

Performing the

4.2.2.2 Performing the Measurement

Starting the

measurement

measurement

Once all the settings have been carried out and checked, the measurement can be
started with the menu item .

In fault mode, the measurements take place in quick succession. Starting at a low value,
the measuring current is increased as linearly a possible by a certain amount with each
measurement and, after 8 measurements, reaches the set maximum value.

The following measured values are shown on the display and continually updated during
the running measuring process as standard:

Change of the absolute value of the

impedance at 50 Hz over the individual

measurements.

Curve of the maximum measuring

current over the individual

measurements.

Current measuring

current

Ending the

measurement

Number of measurements already

carried out

Using the menu item, the diagram types can be switched between as follows:

|Z|/I

U/I

Measuring ends automatically as soon as the 8 measurements have been carried out on
all involved phases. The measurement can be manually deactivated at any time via the

menu item .

Impedance (absolute) and measuring current (maximum)

Current and voltage curve of the period in which the measurement was
carried out (for all measurements up until this point)

Current and impedance values for those

measurements already completed

26

Operation

Inconspicuous measurement:

Conspicuous measurement:

4.2.2.3 Identifying and Locating Faults

Comparing curves

Following the measurement, the measured values and curves can be examined for any
conspicuous jumps and thus the triggering or subsiding of the fault at a certain
measuring current value can be detected.

As is the case even during the measurement, different diagram types can be switched
between using the menu item (see also the previous page).

The curve of current and voltage in particular can be very useful when it comes to
identifying a fault. The following applies in principle: As soon as a fault has been tripped
in the course of the measurements, this is marked by diverging envelope curves.

This is very easy to see in the current curve in the example depicted below. While in the
case of the inconspicuous measurement the envelope curve (broken black line) is
identical for all curves, in the case of the faulty phase two different envelope curves are
clearly recognisable.

In order to be able to undertake a comparison between the measured conductors when
measuring multiple conductors, the following selection menu must be called up via the

menu item:

The conductor to be displayed is selected by turning the rotary encoder.

27

Operation

Locating faults

Information on the position of an identified fault can primarily be gained from the
reflectograms recorded along with the measurement (see page 25).

If this option of fault prelocation is not available, the affected network section at the least
can be identified by means of additional measurements at different connection points
(using a process of elimination).

4.3 Exporting the Measured Data

Once a measurement has been completed, the measured data recorded is written to the
internal memory of the NIM 1000. Measurement data records already contained in the
memory will not be overwritten in this process and, thanks to the non-volatile memory,
the data will be maintained permanently too.

As soon as at least one data measurement record is stored in the memory, an export of
data can be initiated using the menu item in the main menu. Here, all data
measurement records stored in the memory are written into the

\nim1000\measurements\ folder of the plugged-in USB flash drive and deleted upon
successful transfer from the internal memory. The files in CSV format (comma
separated values) can be viewed later in the comfort of the workplace using any
CSV-capable application (e.g. Excel).

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Maintenance and care

Caring for the display

Replacing fuses

5 Maintenance and care

Repair and

maintenance

Storage

Repair and maintenance work has to be carried out by Megger or authorised service
partners using original spare parts only. Megger recommends having the system tested
and maintained at a Megger service centre once a year.

Megger also offers its customers on-site service. Please contact your service centre if
needed.

It is not necessary to open the housing of the device to commission and operate the
system. Opening the housing causes the immediate termination of all warranty claims!

The connections and connection leads of the system must be regularly tested to ensure
that they are free of defects and intact, in accordance with the applicable national and
company-specific arrangements.

If the device is not used for a lengthy period, it should be stored in a dust-free and dry
environment.

Do not clean the display with aggressive products such as solvents or spirits.

Instead, use lukewarm water and a soft, lint-free cloth for wet wiping, or a microfibre
cloth for dry wiping.

Each connection cable is fused in the area of the plug connector with a T 25A H 440V
micro-fuse (6.3 mm x 32 mm) which may be replaced independently if need be.

29

Annex 1: Measuring Accuracy

← Measuring range 300 A ← Measuring range 200 A

Operating

Operating

Operating

U = 115 V

U = 230 V

U = 400 V

Annex 1: Measuring Accuracy

|Z| in mΩ

|Z| in mΩ

|Z| in mΩ

← Measuring range 1000 A ← Measuring range 800 A ← Measuring range 600 A

← Measuring range 600 A ← Measuring range 200 A

uncertainty in %

uncertainty in %

30

uncertainty in %

Annex 1: Measuring Accuracy

Voltage Operating uncertainty Current and measuring range

115 V 3% ± 1 mΩ ≥ 200 A for |Z| > 10 mΩ

100 A for |Z| > 200 mΩ
80 A for |Z| > 500 mΩ

5% ± 1 mΩ 100 A for 40 mΩ < |Z| < 200 mΩ

80 A for 150 mΩ < |Z| < 500 mΩ

10% ± 1 mΩ 100 A for 10 mΩ < |Z| < 40 mΩ

80 A for 30 mΩ < |Z| < 150 mΩ

230 V 3% ± 1 mΩ ≥ 400 A for |Z| > 10 mΩ

300 A for |Z| > 45 mΩ
200 A for |Z| > 150 mΩ
100 A for |Z| > 300 mΩ
80 A for |Z| > 500 mΩ

5% ± 1 mΩ 300 A for 10 mΩ < |Z| < 45 mΩ

200 A for 45 mΩ < |Z| < 150 mΩ
100 A for 200 mΩ < |Z| < 300 mΩ
80 A for 275 mΩ < |Z| < 500 mΩ

10% ± 1 mΩ 200 A for 20 mΩ < |Z| < 45 mΩ

100 A for 80 mΩ < |Z| < 200 mΩ
80 A for 180 mΩ < |Z| < 275 mΩ

400 V 3% ± 1 mΩ ≥ 600 A for |Z| > 10 mΩ

500 A for |Z| > 25 mΩ
400 A for |Z| > 70 mΩ
300 A for |Z| > 190 mΩ
200 A for |Z| > 400 mΩ
100 A for |Z| > 600 mΩ

5% ± 1 mΩ 500 A for 10 mΩ < |Z| < 25 mΩ

400 A for 10 mΩ < |Z| < 70 mΩ
300 A for 90 mΩ < |Z| < 190 mΩ
200 A for 180 mΩ < |Z| < 400 mΩ
100 A for 525 mΩ < |Z| < 600 mΩ
80 A for 600 mΩ < |Z|

10% ± 1 mΩ 300 A for 20 mΩ < |Z| < 90 mΩ

200 A for 50 mΩ < |Z| < 180 mΩ
100 A for 300 mΩ < |Z| < 525 mΩ
80 A for 500 mΩ < |Z| < 600 mΩ

31

Annex 2: Measuring Range

Annex 2: Measuring Range

Voltage

115 V 300 A

200 A

100 A

80 A

230 V 600 A

500 A

400 A

300 A

200 A

100 A

80 A

400 V 1000 A

900 A

800 A

700 A

600 A

Current range Measuring range

|Z| < 40 mΩ

|Z| < 300 mΩ

|Z| < 1100 mΩ

|Z| < 2500 mΩ

|Z| < 40 mΩ

|Z| < 150 mΩ

|Z| < 300 mΩ

|Z| < 500 mΩ

|Z| < 1000 mΩ

|Z| < 2500 mΩ

|Z| < 5000 mΩ

|Z| < 60 mΩ

|Z| < 120 mΩ

|Z| < 200 mΩ

|Z| < 300 mΩ

|Z| < 430 mΩ

500 A

400 A

300 A

200 A

80 A / 100 A

|Z| < 620 mΩ

|Z| < 900 mΩ

|Z| < 1400 mΩ

|Z| < 2300 mΩ

|Z| < 5000 mΩ

32

se na likvidaci starých elektrických spotřebičů v blízkosti svého působiště.

Dit symbool duidt aan dat het product met dit symbool niet verwijderd mag worden als gewoon huishoudelijk afval. Dit is een product voor industrieel gebruik, wat betekent

houdelijk afval. Als u dit product wilt verwijderen, gelieve dit op de juiste manier te doen en het naar een

nabij gelegen organisatie te brengen gespecialiseerd in de verwijdering van oud elektrisch materi aal.

продукт, не бива да се изхърля и в

Dette symbol viser, at det produkt, der er mar keret på denne måde, ikke må kasseres som almindeligt husholdningsaffald. Eftersom det er et B2B produkt, må det heller ikke

bortskaffe gammelt el-udstyr.

Sellise sümboliga tähistatud toodet ei tohi käidelda tavalise olmejäätmena. Kuna tegemist on B2B-klassi kuuluva tootega, siis ei tohi seda viia kohal ikku jäätmekäitluspunkti.

, ottakaa yhteys lähimpään vanhojen

Ce symbole indique que le produit sur lequel il figure ne peut pas être éliminé comme un déchet ménager ordinaire. Comme il s’agit d’un produit B2B, il ne peut pas non plus

proche de chez vous.

Cuireann an siombail seo in iúl nár cheart an táirgeadh atá marcáilte sa tslí seo a dhiúscairt sa chóras fuíoll teaghlaigh. Os rud é gur táirgeadh ghnó le gnó (B2B) é, ní féidir

Elektroaltgeräte in Ihrer Nähe.

Αυτό το σύμβολο υποδεικνύει ότι το προϊόν που φέρει τη σήμανση αυτή δεν πρέπει να απορρίπτεται μαζί με τα οικιακά απορρίματα. Καθώς πρόκειται για προϊόν B2B, δεν

παρακαλούμε όπως να το παραδώσετε σε μία υπηρεσία συλλογής

ηλεκτρικού εξοπλισμού της περιοχής σας.

Questo simbolo indica che il prodotto non deve essere smaltito come un normale rifiuto domestico. In quanto prodotto B2B, può anche non essere smaltito in centri di

Šī zīme norāda, ka iztrādājumu, uz kura tā atrodas, nedrīkst izmest kopā ar parastiem mājsaimniecības atkritumiem. Tā kā tas ir izstrādājums, ko cits citam pārdod un lieto

izmest atkritumos, tad rīkojieties pēc noteikumiem un nogādājiet to tuvākajā vietā, kur īpaši nodarbojas ar vecu elektrisku ierīču savākšanu.

Šis simbolis rodo, kad juo paženklinto gaminio negalima išmesti kaip paprastų buitinių atliekų. Kadangi tai B2B (verslas verslui) produktas, jo negalima atiduoti ir buitinių

gammelt elektrisk utstyr.

Ten symbol oznacza, że produktu nim opatrzonego nie należy usuwać z typowymi odpadami z gospodarstwa domowego. Jest to produkt typu B2B, nie należy go więc

eliminação de equipamento eléctrico antigo, próxima de si.

Acest simbol indică faptul că produsul marcat în acest fel nu trebuie aruncat ca şi un gunoi menajer obişnuit. Deoarece acesta este un produs B2B, el nu trebuie aruncat nici

echipamentelor electrice uzate.

Este símbolo indica que el producto así señalizado no debe desecharse como los residuos domésticos normales. Dado que es un producto de consumo profesional,

esté especializada en el tratamiento de residuos de aparatos eléctricos usados.

Den här symbolen indikerar att produkten inte får blandas med normalt hushållsavfall då den är förbrukad. Eftersom produkten är en så kallad B2B-produkt är den inte

eller återvinningsstationer då den är förbrukad. Om ni vill avfallshantera den här

Tento symbol indikuje, že výrobek nesoucí takovéto označení nelze likvidovat společně s běžným domovním odpadem. Jelikož se jedná o produkt obchodovaný mezi
podnikatelskými subjekty (B2B), nelze jej likvidovat ani ve veřejných sběrných dvorech. Pokud se potřebujete tohoto výrobku zbavit, obraťte se na organizaci specializující

dat het ook niet afgeleverd mag worden aan afvalcentra voor huis

This symbol indicates that the product which is marked in this way should not be disposed of as normal household waste. As it is a B2B product, it may also not be disposed
of at civic disposal centres. If you wish to di spose of this product, please do so properly by taking it to an organisation specialising in the disposal of old electrical equipment
near you.

Този знак означава, че продуктът, обозначен по този начин, не трябва да се изхвърля като битов отпадък. Тъй като е B2B
градски пунктове за отпадъци. Ако желаете да извърлите продукта, го занесете в пункт, специализиран в изхвърлянето на старо електрическо оборудване.

bortskaffes på offentlige genbrugsstati oner. Skal dette produkt kasseres, skal det gøres ordentligt ved at bringe det til en nærliggende organisation, der er specialiseret i at

Kui soovite selle toote ära visata, siis viige see lähimasse vanade elektriseadmete käitlemisele spetsialiseerunud ettevõttesse.

Tällä merkinnällä ilmoitetaan, että kysei sellä merkinnällä varustettua tuotetta ei saa hävittää tavallisen kotitalousjätteen seassa. Koska kyseessä on yritysten välisen kaupan

tuote, sitä ei saa myöskään viedä kuluttajien käyttöön tarkoitettuihin keräyspisteisiin. Jos haluatte hävittää tämän tuotteen

sähkölaitteiden hävittämiseen erikoistuneeseen organisaatioon.

être déposé dans une déchetterie municipale. Pour éliminer ce produit, amenez-le à l’organisation spécialisée dans l’élimination d’anciens équipements électriques la plus

é a dhiúscairt ach oiread in ionaid dhiúscartha phobail. Más mian leat an táirgeadh seo a dhiúscairt, déan é a thógáil ag eagraíocht gar duit a sainfheidhmíonn i ndiúscairt

sean-fhearas leictrigh.

Dieses Symbol zeigt an, dass das dami t gekennzeichnete Produkt nicht al s normaler Haushaltsabfall entsorgt werden soll. Da es sich um ein B2B-Gerät handel t, darf es
auch nicht bei kommunalen Wertstoffhöfen abgegeben werden. Wenn Sie dieses Gerät entsorgen möchten, bringen Sie es bitte sachgemäß zu einem Entsorger für

πρέπει να απορρίπτεται σε δημοτικά σημεία απόρριψης. Εάν θέλετε να απορρίψετε το προϊόν αυτό,

Ez a jelzés azt jelenti, hogy az ilyen jelzéssel ellátott terméket tilos a háztartási hulladékokkal együtt kidobni. Mivel ez vállalati felhasználású termék, tilos a lakosság
számára fenntartott hulladékgyűjtőkbe dobni.Ha a terméket ki szeretné dobni, akkor vigye azt el a lakóhelyéhez közel működő, elhasznált elektromos berendezések
begyűjtésével foglalkozó hulladékkezelő központhoz.

smaltimento cittadino. Se si desi dera smaltire il prodotto, consegnarlo a un organismo specializzato in smaltimento di apparecchiature elettriche vecchie.

tikai uzņēmumi, tad to nedrīkst arī izmest atkritumos tādās izgāztuvēs un atkritumu savāktuvēs, kas paredzētas vietējiem iedzīvotājiem. Ja būs vajadzīgs šo izstrādājumu

atliekų tvarkymo įmonėms. Jei norite išmesti šį gaminį, atlikite tai tinkamai, atiduodami jį arti jūsų esančiai specializuotai senos elektrinės įrangos utilizavimo organizacijai.

Dan is-simbolu jindika li l-prodott li huwa mmarkat b’dan il-mod m’għandux jintrema bħal skart normali tad-djar. Minħabba li huwa prodott B2B , ma jistax jintrema wkoll
f’ċentri ċiviċi għar-rimi ta’ l-iskart. Jekk tkun tixtieq tarmi dan il-prodott, jekk jogħġbok għamel dan kif suppost billi tieħdu għand organizzazzjoni fil-qrib li tispeċjalizza fir-rimi ta’
tagħmir qadim ta’ l-elettriku.

Dette symbolet indikerer at produktet som er merket på denne måten ikke skal kastes som vanlig husholdningsavfall. Siden dette er et bedriftsprodukt, kan det heller ikke
kastes ved en vanlig miljøstasjon. Hvis du ønsker å kaste dette produktet, er den riktige måten å gi det til en organisasjon i nærheten som spesialiserer seg på kassering av

przekazywać na komunalne składowiska odpadów. Aby we właściwy sposób usunąć ten produkt, należy przekazać go do najbliższej placówki specjalizującej się w
usuwaniu starych urządzeń elektrycznych.

Este símbolo indica que o produto com esta marcação não deve ser deitado fora juntamente com o lixo doméstico normal. Como se trata de um produto B2B, também não
pode ser deitado fora em centros cívicos de recolha de lixo. Se quiser desfazer-se deste produto, faça-o correctamente entregando-o a uma organização especializada na

la centrele de colectare urbane. Dacă vreţi să aruncaţi acest produs, vă rugăm s-o faceţi într-un mod adecvat, ducând-ul la cea mai apropiată firmă specializată în colectarea

Tento symbol znamená, že takto označený výrobok sa nesmie likvidovať ako bežný komunálny odpad.Keďže sa jedná o výrobok triedy B2B, nesmie sa likvidovať ani na
mestských skládkach odpadu. Ak chcete tento výrobok likvidovať, odneste ho do najbližšej organizácie, ktorá sa špecializuje na likvidáciu starých elektrických zariadení.

Ta simbol pomeni, da izdelka, ki je z njim označen, ne smete zavreči kot običajne gospodinjske odpadke. Ker je to izdelek, namenjen za druge proizvajalce, ga ni dovoljeno
odlagati v centrih za civilno odlaganje odpadkov. Če želite izdelek zavreči, prosimo, da to storite v skladu s predpisi, tako da ga odpeljete v bližnjo organizacijo, ki je

specializirana za odlaganje stare električne opreme.

tampoco debe llevarse a centros de recogida selectiva municipales. Si desea desechar este producto, hágalo debidamente acudiendo a una organización de su zona que

avsedd för privata konsumenter, den får således inte avfallshanteras på allmänna miljö­produkten på rätt sätt, ska ni lämna den till myndighet eller företag, specialiserad på avfallshantering av förbrukad elektrisk utrustning i ert närområde.

33