Megger LCB2500, LCB2000 User Manual

RCD & LOOP TESTERS
MEGGER LCB2000/2500

User Guide

MEGGER

®

Dear Customer,
Thank you for purchasing one of the new premium range

of Combinations products from AVO International. The
Combinations concept was created after listening to the
views of many users, and combine quality and versatile
features with the reliability and dependability you expect
from MEGGER products. Every instrument is designed
and manufactured to exacting standards and as such is
guaranteed for a full three years.

The MEGGER LCB2000 and LCB2500 are part of an
advanced range of combined loop and circuit breaker
testers designed to fully test RCDs and measure loop
impedance and prospective short circuit current, (PSCC),
on single and three phase systems rated up to 300V ac
r.m.s. to earth. Designed to comply with all relevant wiring
regulations, the units feature both standard and low
current loop test ranges guaranteed not to trip RCDs
rated at 30mA and above. Acomprehensive range of
RCD test facilities is provided to cater for the most
demanding situations whilst ingenius facilities such as
ramp and auto-sequence tests provide diagnostics for
troubleshooting nuisance tripping and reduce the time
taken for a series of tests considerably.

2

Results are clearly indicated on a large backlit liquid
crystal display. The LCB2500 also allows results to be
stored against specific circuit and distribution board
references. This instrument is directly compatible with

®

PowerSuite™for Windows™and NICEone

AVO
software and stored data may be quickly downloaded for

™

creation of professional installation test certificates.
Alternatively direct connection to a serial printer is
possible.

Contents

Safety Warning 4
Function Keys and Warning Symbols 5
Initial Setup 6
General Description 7
Wiring Diagram 9
Operation 10
Specifications 29
Accessories 33
Publications 34
Loop Resistance Tables 35
Repair and Warranty 36

Symbols used on the instrument are:

Caution: Refer to
accompanying notes

Maximum nominal system
voltage of 440V

Maximum 300V a.c.
CATIII to Earth

3

SAFETY WARNINGS

★ Safety Warnings and Precautions must be read and understood before the instru-

ment is used. They must be observed during use.

★ Continuity of protective conductors and earthed equipotential bonding of new or

modified installations must be verified before carrying out an earth fault loop
impedance test, or RCD test.

★ Circuit connections and exposed metalwork of an installation or equipment under

test must not be touched.

★ Do not move the rotary selector switch position while a test is in progress.
★ The LCD ‘neon’ voltage indicators cannot reveal a Neutral-Earth reversal.
★ The instrument should not be used if any part of it is damaged.
★ Test leads, probes and crocodile clips must be in good order, clean and with no

broken or cracked insulation.

NOTE

THE INSTRUMENTS MUST ONLY BE USED BY SUITABLY TRAINED AND COMPETENT PER-

4

Function Keys and Warning Symbols

KEYS:

ENTER SAVE

BACKLIGHT

RCD TEST TYPE DOWN

RCD TYPE UP

TEST EXIT

Note: On LCB2000 storage and download

functions are not available and are
not marked on the keys

Condition

System error

Low battery

Touch pad

>100V

Supply voltage
and frequency

out of range
Thermal trip

operated

Supply

interrupted

during test

Noise

Fuse ruptured

Memory full

Memory

corrupted

> or <

and limit

value

CauseDisplay Action

Hardware or
software fault.

Battery voltage
too low.

Earth voltage
too high.

Supply voltage or
frequency too high or
low for test.

Too rapid testing with no
pauses for heat
dissipation.

RCD tripped or
supply failure.

Excessive external
supply noise during
earth loop or RCD test.

Blown fuse.

Results memory full.

Results memory
unintelligible.

Switch ‘Off’, then ‘On’
and attempt re-test.

Replace battery.

Check installation or
wiring to the instrument.

—

Pause between tests
to allow cooling.

Confirm RCD rating and
check for excess earth
leakage current.

Identify and rectify, or
wait and re-test.

Return instrument
for repair.

Download results
and clear memory.

Press TEST to
attempt recovery.

5

Initial Setup

Instrument Setting
The instrument setting modifies the way the instrument

behaves, shown in the following table.

Setting A (Europe)
Line and Neutral Swap

allowed.
Auto Sequence RCD

does 5I test.
After RCD trip test,

contact voltage
displayed first.

1

⁄2I no trip RCD test not

2s
performed.

To change the setting:

1. Press and hold the Backlight key, then turn the
rotary selector switch from the OFF position to the
RCD 150mA 40ms position. The current setting will
be displayed.

2. To change the setting, toggle the I key until the
required setting is displayed.

3. To save the new setting, press the SAVE key. The
bleeper sounds and SET is displayed. To leave the
setting as it was, press the EXIT key.

6

Setting b (UK)
Line and neutral swap

not allowed.
Auto Sequence RCD

does 150mA test.
After RCD trip test,

trip time or current
displayed first.

1

⁄2I no trip RCD test

2s
performed.

Reset Factory Default Settings
The instrument will remember certain values such as

the VAR range RCD test current, even if the instrument
is switched off and the battery removed.

These can be reset to factory default settings as follows:

1. Press and hold the BACKLIGHT key, then turn the
rotary selector switch from the OFF position to the
RCD 150mA 40ms position. The current setting will
be displayed. Release the BACKLIGHT key.

2. Press the up and down keys together. The code clr
is displayed.

3. Confirm the operation by pressing the SAVE key, or
abort by pressing any other key. The current setting
will be displayed.

General Description

This instrument has been designed to fully test RCDs
and measure loop impedance and PSCC on single and
three phase systems with a rated voltage up to
300V a.c. r.m.s. to earth. It has been designed to
comply with U.K., European and other international
wiring regulations and standards.

Measured values are displayed on a large backlit digital
LCD. With the LCB2500 these values may also be stored
in internal memory for later recall to display, direct printing
to a standard serial printer, or downloaded to a PC for
storage, analysis and report generation.

Key Features
Storage of test results in memory (LCB2500 only)
Selectable backlight
Large clear liquid crystal display
Operates regardless of mains polarity
Automatic test start on voltage detection

Loop Tests
Direct indication of short circuit current
Phase-phase (up to 480V), phase-neutral and
phase-earth tests
No trip loop impedance tests with a resolution
down to 0.01Ω
No neutral needed for line to earth testing
(except for No Trip Loop L-PE 0.01Ω)

RCD tests
Tests selective (delayed), general and d.c. sensitive
RCDs

Contact voltage and loop resistance displayed
Selectable test current for programmable devices
Auto sequence test
Ramp test

General
Supply voltage and frequency measurement
Three Phase sequence indication
Mains outlet polarity indication

Application
The instrument may be be connected live to earth or

between live conductors of systems that have a rated
voltage of 300V a.c. rms to earth and an Installation
(Overvoltage) Category III or lower. This means that the
instrument may be connected to any fixed wiring of a
building installation, but not to primary supply circuits
such as overhead cables. To maintain user safety and
ensure accurate measurements, only use the test leads
supplied or recommended for use with this instrument.

The instrument is fuse protected to 440V 10kA. The
maximum current which could flow through this fuse in
the case of a fault is limited to 10 kA by the impedance
of the test leads.

When the low battery symbol appears, the cells are
nearly exhausted and should be replaced as soon as
possible. When the battery is exhausted, the instrument
will not perform tests and the cells must be replaced.
Use alkaline cells IEC LR6 (AA) or 1,5V nickel cadmium

7

cells only.
To install or replace the cells, disconnect the test leads,

switch the instrument off and loosen the captive screws
holding the battery compartment cover in place.
Remove the cover, lift out and disconnect the battery
holder to access the cells. Replace the cells, ensuring
that correct polarity is observed (shown on battery

Incorrect battery cell polarity

can cause electrolyte leakage resulting in

damage to the instrument

holder moulding).
Carefully re-connect the battery holder to the connector,

replace the battery holder in the compartment, and re­secure the cover. Remove the cells if the instrument is
not going to be used for any extended period of time.
Stored results are retained when the battery is
disconnected.

8

Test Leads
All test leads form part of the measuring circuit of the

instrument and must not be modified or changed in any
way, or be used with any other electrical instrument or
appliance. The power cord supplied with the Installation
Testers is a test lead that forms part of the measuring
circuit of the instrument. The overall length of this lead
must not be altered. If the power cord plug is not
suitable for your type of socket outlets, do not use an
adaptor. You may change the plug once only by cutting
the cord as close to the plug as possible and fitting a
suitable plug.

The colour code of the cord is:
Earth (Ground) Yellow/Green
Neutral Blue
Phase (Line) Brown

Note: A plug severed from the power cord must be

destroyed, as a plug with bare conductors is
hazardous in a live socket outlet.

Wiring Diagram

LOOP L-PE
LOOP L-N

Supply

Black

RCD

Red

Green

RCD

LOOP L-PE 0.1Ω (no trip)

LOOP L-PE 0.01Ω (no trip)

LOOP L-N

Black

Red

Black

Green

LOOP L-L

L1
L2
L3
N

P-E

Red

9

Operation

Backlight
The display backlight gives a clear display of

measurements in poor lighting conditions. The backlight
will briefly operate when the instrument is switched on.
To switch the backlight on, press the backlight key (see
key on page 4). Press the key again to switch the
backlight off.

To conserve battery power, the backlight will
automatically switch off after about 15 seconds (if the
battery voltage is low, this period is automatically
reduced).

Auto Shut-off
To extend battery life after a period of instrument

inactivity the instrument will switch itself off, preceded by
a series of bleeps. To switch the instrument back on,
press any key other than the TEST key.

Switched Probe SP2
This accessory can be used anywhere that the 2-wire

lead set is specified in this User Guide. The press switch
on the probe duplicates the function of the TEST key on
the instrument, allowing quick and easy testing.

Checking Earth Potential
To quickly distinguish live and earth, this feature provides

display indication if a voltage greater than 100V exists
between the earth connection and your finger.

1. In any switch position except OFF and RCL

10

(LCB2500 only), connect the earth connection (black
for the 2-wire lead set, green for the 3-wire lead set)
to earth.

2. Touch a finger to the metal pad on the top. This is
safe and will not endanger you.

3. If a voltage greater than 100V exists between the
finger (normally at earth potential) and the earth
wire, the warning symbol is displayed.

Voltage and Frequency Measurement
This instrument will display the supply voltage and

frequency in all switch positions except RCL and OFF.
The ENTER key will alternate between voltage and
frequency.

Power plug connection

1. Insert the power cord plug into an installation socket.

2. Supply voltage and polarity are displayed.

3. Press ENTER to alternate between supply voltage
and frequency.

3-Wire Lead Set Connection
If an installation socket is not available and it is
necessary to connect to all three conductors, use the 3­wire lead set.

1. On a single phase system connect the red lead to
phase, the black to neutral and the green to earth.

2. Supply voltage and polarity are displayed.

3. Press ENTER to alternate between supply voltage
and frequency.

Note: For connection to a three phase system, see

‘Determining Phase Sequence’.

When connected the instrument will display the Line to
Earth voltage except on the loop L-N switch position
when the line to neutral voltage is displayed or shown.

Polarity Indication
If connected to a single phase power supply by a plug

or by the 3-wire lead set, three LCD ‘neons’ marked L­PE, N-PE and L-N respectively will indicate supply
polarity. If a voltage is detected between their respective
two wires, the ‘neon(s)’ will activate. A ‘neon’ will usually
flash if one connection is open circuit.

Note: The presence of a voltage between phase and

earth does not prove earth continuity, as the earth
could have a high resistance and a voltage would
still be measured. To test earth continuity refer to
the sections on loop resistance or RCD testing.

If Setting A(see page 4) is set, the instrument will
automatically switch Line and Neutral as appropriate.
This enables a test to be performed without inverting the
plug connections. The live terminal of the wall socket is
identified by the addition of a separate symbol adjacent
to the ‘neons’.

Setting A (Europe)

L-PE N-PE L-N

Normal Supply (1)

Normal Supply (2)

Neutral Live

Neutral Open Circuit

Earth Open Circuit

Setting b (U.K.)

L-PE N-PE L-N

Normal Supply

L-N Reversed

Neutral Live

Neutral Open Circuit

Earth Open Circuit

11

Operation

Determining Phase Sequence
When connected to all conductors of a three phase

system, the instrument automatically displays the
sequence of phase rotation.

Connect the the Installation Testers as follows:­Line 1 Red phase Red lead

Line 2 Yellow phase Green lead
Line 3 Blue phase Black lead

If connected as above, the symbol is displayed
when the sequence is
1:2:3, or Red-Yellow-Blue. The symbol is displayed
when the sequence is 1:3:2,
or Red-Blue-Yellow. If one of the lines is faulty, neither
of the symbols is displayed and the normal ‘neon’
polarity indication is shown.

In the Loop L-N switch position the voltage between the
red and black leads is displayed. In other switch
positions the voltage between the red and green leads
is measured and displayed.

12

Loop Impedance measurement
Loop impedance measurement of 0,01Ω up to 3,00kΩ

can be made via installation sockets using the plug
terminated test lead, or at any other convenient point on
the installation using the two wire lead set. If Setting A
(see page 4) is selected when using the plug terminated
lead set, the polarity of the mains socket is immaterial.
Line and Neutral will be swapped if necessary, and an
indication given on the display. Setting b requires Line
and Neutral to be fixed.

Test results may be adversely affected by
supply voltage fluctuations or electrical noise
during measurement. It is recommended that

tests are repeated and the results verified, if

measurment results are considered abnormal.

The Installation Testers will measure the loop resistance
from the supply end of the standard test leads, allowing
for their resistance.

Automatic Testing

To aid rapid testing, the instruments can be set to
start a test automatically when connected to the
supply. This may be of use for example, when using
a clip and a probe. Select the range required and
press the test key without the supply present. The
instrument will display <100V for approximately
30 seconds. Apply the supply voltage within this time
and the instrument will pause before performing one
test automatically.

Phase to Neutral or Earth loop impedance measurement
(at a power socket):

1. Select Loop L-PE or L-N as required.

2. Insert the plug into an installation socket.

3. Supply voltage and polarity are displayed.

4. Press the TEST key.

5. Measured loop value is displayed.
On completion of this test, prospective fault current can

be displayed by pressing the ENTER key.
If desired the test can be repeated by pressing TEST

again.

Phase-Earth loop impedance measurement (not at a
power socket):

If an installation socket is not available, use the 3-wire
lead set.

1. Select Loop L-PE.

2. Connect the red lead to phase and the green lead to
earth. No connection to neutral is required.

3. Supply voltage is displayed.
Note: If the black lead is not connected to neutral,
although displayed the polarity indications are invalid.

4. Press the TEST key.

5. Measured loop value is displayed.

On completion of this test, the prospective fault current
can be displayed by pressing the ENTER key.

If desired the test can be repeated by pressing TEST
again.

Bonded Metalwork Testing (1)
This test is performed using the three wire lead set.

1. Connect the green lead to the bonded metalwork.

2. Connect the red lead to phase.

3. Select Loop L-PE.

4. Supply voltage is displayed.

5. Press the TEST key.

6. Measured resistance value is displayed.

13

Operation

Bonded Metalwork Testing (2)
This test can also be performed using the optional earth

bond test lead, allowing connection to an installation
socket.

1. Connect the black flying test lead to the bonded
metalwork.

2. Insert the power plug test lead into a socket
(receptacle).

3. Select Loop L-PE.

4. Supply voltage is displayed.

5. Press the TEST key.

6. Measured resistance value is displayed.

Phase-Neutral or Phase-Phase loop resistance
measurement

To measure the loop resistance of a circuit
Phase-Neutral, or between two phases of a multi-phase
system, connect using the 3-wire lead set.

1. Connect the red lead to phase and the black lead to
neutral or the other phase. There is no need to
connect the green lead.

2. Select Loop L-N/L-L.

3. The supply voltage is displayed. The polarity
indications are invalid and should be ignored.

4. Press the TEST button.

5. Measured loop resistance is displayed.

The prospective fault current may be displayed by
pressing the ENTER key.

14

Prospective Short Circuit Current measurement (PSCC)
The PSCC of a circuit is the largest Prospective Fault

Current (PFC). In a single phase system, this would be
the larger of the earth loop PFC and the neutral loop
PFC. In a multi-phase system phase-phase loops also
need to be considered and these can be measured
using the Loop L-L switch position.

When the instrument measures the loop resistance, it
also calculates the PFC. After any loop test, this may be
displayed by pressing the ENTER key.

The PFC is calculated by using the sum:-

The supply voltage used in the calculation depends on
the measured voltage and the configuration of the
instrument. As supplied, the instruments are configured
as follows:-

Actual Measured Voltage

>150V and <300V

Nominal supply voltage

Loop resistance

150V

>300V

Assumed Nominal Voltage

110V
230V
400V

PFC measurement accuracy
An accurate PFC measurement requires an accurate

measurement of the loop resistance. The difference of a
few digits in the loop resistance measured will have a
large effect on the PFC displayed.

Errors can be reduced by:-

• Using the 3 wire lead set with prods and making a
firm connection to clean conductors.

• Making several tests and taking the average.

• Ensuring that potential sources of noise in the
installation are isolated (switched off), eg:
automatically switched loads or motor controllers

• Ensuring that the instrument is calibrated.

No trip loop-testing
The Loop L-PE 0.1Ω range is a low test current earth

loop resistance measurement range. The 15mA current
enables the earth loop resistance to be measured
without tripping all types of RCDs with a rated current of
30mA or higher. Tests may be made via installation
sockets with the plug terminated test lead, or at any
other point using the 2-wire lead set. Connections are
required to Line and Earth only.

The Loop L-PE 0.01Ω range is a high resolution low test
current earth loop resistance measurement range. It
requires a connection to neutral, but allows quick and
accurate measurement of the earth loop resistance without
tripping all RCDs with a rated current 30mA or higher.

If a neutral connection is not possible, then the Loop
L–PE 0.1Ω must be used. Connecting the black lead to
earth and performing the Loop L-PE 0.01Ω will cause an
RCD to trip.

15mA-Phase to Earth loop impedance measurement (at
a power socket)

1. Select Loop L-PE 0.1Ω or 0.01Ω as appropriate.

2. Insert the plug into an installation socket.

3. Supply voltage and polarity are displayed.

4. Press the TEST key. Test progress is displayed.

5. Measured loop value is displayed
If desired the test can be repeated by pressing TEST

again.
15mA-Earth loop impedance measurement (not at a

power socket)

1. Select Loop L-PE 0.1Ω or 0.01Ω as appropriate.

2. Firmly connect the red lead to phase and the green
lead to earth. Connection to neutral with the black
lead is only required for the Loop L-PE 0.01Ω range.

3. Supply voltage is displayed.

4. Press the TEST key. Test progress is displayed.

5. Measured loop value is displayed.

If desired the test can be repeated by pressing TEST
again.

After a Loop L-PE 0.01Ω test, the component
resistances of the circuit under test may be stepped
through by pressing the ENTER key.

15

Operation

They will be shown in the following order:

Loop L-PE

PFC L-PE

Loop L-N

PFC L-N

R1
R2
Rn

R1

Rn
R2

All results may be stored under a single circuit
reference. See ‘Test Result Storage’.

16

Method of measurement
The phase-earth, phase-neutral or phase-phase loop

resistance can be measured. The instrument takes a
current from the supply and measures the difference
between the unloaded and loaded supply voltages.
From this difference it is possible to calculate the loop
resistance. The test current will vary from 15mA to 40A,
depending on supply voltage and the loop resistance
value. The test duration will depend on the loop
resistance value.

The Loop L-PE 0.01Ω range performs a test with a current
up to 25A flowing Line to Neutral and the resistance of the
source and line wires are measured. This is followed by a
current of 15mA flowing Line to Earth and the resistance
of the earth wires are measured.

Possible sources of error
The reading depends on a measurement of the supply

voltage and therefore noise or transients caused by other
equipment during the test could cause an error in the
reading. One way to check for these is to do two tests
and look for any difference in value. The instrument will
detect some sources of noise and warn the user, where
other instruments may give an incorrect reading. Any
leakage current as a consequence of other appliances
connected to the supply under test may affect the
reading. If the Phase-Earth loop is being measured, this
leakage may be due to filter capacitors, etc.

RCD Testing
The instrument can test the operation of a variety of

types of Residual Current Devices (RCD), measure the
phase to earth loop resistance, and the contact voltage
of the installation. If Setting A(see page 4) is selected
when using the plug terminated lead set, the polarity of
the mains socket is immaterial. Line and Neutral will be
swapped if necessary, and an indication given on the
display. Setting b requires Line and Neutral to be fixed.

Pre-Test Configuration
Before performing an RCD test it is necessary to ensure

that the instrument is correctly configured for the rated
current and the specific type of RCD to be tested, and
for the type of test to be performed.

RCD Current Rating
From information given on the RCD to be tested, select

the RCD current rating on the rotary switch.
RCD VAR switch position
This position enables any RCD with a non standard

rated current between 10 mA and 1000 mA to be tested.
The test is performed at the selected current, taking the
5I multiplier into consideration

1. Select (RCD) VAR.

2. Toggle the ENTER key to display the test current.

3. Press the up and down keys until the required test
current is displayed. (LCB2000: These are marked

RCD Test Type and RCD Type). Hold a key down to
auto-repeat.

4. Press the ENTER key. The Supply Voltage, Test
Type and RCD Type are shown. These may be set
up as given in the following sections.

Ramp and Auto Sequence tests are only available

on the RCD VAR if the test current is set to 10mA.

The maximum possible test current (including 5I

multiplier) is 1000mA (300mA for d.c. sensitive

RCDs). These limits are halved if the supply voltage

is less than 200V.

Setting precision:

10-50mA 1mA steps
50-500mA 5mA steps
500mA-1000mA 10mA steps

17

Operation

RCD Type
Pressing the TYPE key displays the RCD type symbols.

From information given on the RCD to be tested, select
and set the type of RCD.

Symbol Test

General

Selective (delayed)

D.C. sensitive

D.C. Sensitive RCDs
Some RCDs are electromechanical devices which can

be saturated by the presence of d.c. Therefore if a d.c.
fault occurs, or an a.c. fault occurs in the presence of
quite a small direct current, the RCD may not trip. In this
way the RCD is disabled and this becomes a potential
hazard. Because of this, ‘d.c. sensitive’ RCDs are
available.

18

Selective or Time delayed RCDs
In some cases it may be necessary to have an RCD

protecting an individual circuit or group of circuits. If a
fault occurs, the RCD nearest to the fault should trip to
clear it, maintaining supplies to the other circuits.
Selective RCDs (normal symbol) are used to
discriminate faults occurring on circuits, and these have
a minimum as well as a maximum trip time.

Type of Test

Display Type of Test

1

⁄2I

0°

180°

No Trip

Trip Test

Trip Test

Ramp Test

5I

Trip Test

Pressing the I key displays the Type of Test symbols individually
in sequence. Select the type of the test to be perofrmed.

Description
Performs a no-trip test at half the

rated current of the selected
RCD.
The test measures the earth loop
resistance and contact voltage.

Trip test at the rated current of
the selected RCD. A
carried out before this, and the
resistance and voltage are
available after the test. The test is
always started on a zero crossing
when the instantaneous voltage
is on the rise.

As above, but the test is always
started on a zero crossing when
the voltage is on the fall.

Test current increases from half
the rated current of the RCD. The
result is the current at which the
trip opens.

Trip test at 5 x the rated current
of the selected RCD. The choice
of 0° or 180° gives greater
accuracy of measurement. A
test is carried out before this, and
the resistance and voltage are
available after the test.

1

⁄2I test is

1

⁄2I

No Trip Tests
When an 1⁄2I (or No Trip) test is performed, the loop or

earth resistance is measured, and in Setting b, a two
second No Trip test follows.

Loop resistance measurement
The loop resistance is measured at half the rated RCD

current selected. Contact voltage is displayed which is
the loop resistance multiplied by the rated RCD current.
A high loop resistance will cause the instrument to
display >90V, and safely abort the test.

2 second No Trip test (Setting B only)
This tests that the RCD does not trip when half the rated

operating current of the RCD is drawn for 2 seconds.
Tripping of the RCD will indicate that it is over sensitive, or
that excessive earth leakage current is being drawn in the
system. The load put onto the circuit is resistive and
therefore the test current is sinusoidal if the supply is
sinusoidal.

No Trip testing
The test is the same for all RCD types. Select the Rated

Current, the RCD Type and
installation and press the TEST key. If the settings are

1

⁄2I. Connect to the

correct, and the RCD is in order, the RCD trip should not
operate and the contact voltage will be displayed. If the
RCD trip does operate during the test, the message is
displayed. This could be due to incorrect current rating
selection, excessive leakage current in the circuit, or a

19

Operation

faulty RCD. If the problem is excessive leakage current,
the source of the problem must be located and rectified
before a trip test is performed, otherwise the result of the
trip test will be invalid. Loop resistance can be shown by
pressing the ENTER key.

Trip Tests
The instrument will measure the trip time or trip current of

common, selective (time delayed) and d.c. sensitive RCDs.
The trip time is measured by timing the period from the
application of a resistive load to when the supply fails.

Some RCDs are sensitive to the polarity of the supply,
i.e. whether the test current is applied with the
instantaneous rising or falling. Tests should therefore be
performed with the polarity 0° and 180° and the
maximum time taken.

D.C. sensitive RCDs are tested with a pulsed waveform.
The rms current is √2 x the rated operating current of
the RCD. As with the normal RCDs, these should be
tested with 0° and 180° polarity.

As the No Trip test can affect the trip time of some
selective RCDs, there is a 30 second delay before
activation of the trip test. It is possible to override this
delay by pressing the TEST button when the instrument
is counting (1...2...3...).

Note: Significant operating errors can occur if loads,

particularly rotating machinery and capacitive
loads are left connected during tests.

20

RCD Rating D.C. sensitive RMS currents
10mA 14,1mA
30mA 42,4mA
100mA 141mA
300mA 424mA
500mA Not available
1000mA Not available

†

For supply voltages above 200V only.

Trip Testing (measuring the trip time)

1. Select the RCD rated current on the rotary switch.

2. Connect to the supply as detailed below.

3. Select the required test using the TEST TYPE key –
0° or 180° for the normal trip tests, or 5I together
with 0° or 180° for a 5I test.

4. Select the RCD type using the TYPE key.

5. Press the TEST button.

If the RCD trips, the first display depends upon the
Setting selected.
Setting A: The contact or fault voltage is displayed with
the Loop or earth resistance and trip time available by
pressing the ENTER key.
Setting b: The trip time is displayed with the contact/fault
voltage and Loop/earth resistance available by pressing
the ENTER key.

†

150mA 40ms test
When an RCD is fitted for personal protection, a test

current of 150mA must cause the RCD to trip in less
than 40ms.

1. Select 150mA 40ms on the rotary switch.

2. Connect to the supply as detailed below.

3. Select and set the Trip Test to 0° or 180° using the
TEST TYPE key.

4. Press the TEST key.

If the RCD trips within 40ms, the trip time is displayed.
Ramp Test (measuring the trip current)
The trip current is measured by applying a test current

of half the rated trip current and increasing this every
200 ms. When the supply is cut, the current flowing is
recorded and displayed.

A low trip current could be due to an overly sensitive
RCD, or to leakage currents in the supply.

To determine the trip current of an RCD.

1. Select an appropriate RCD rated current on the
rotary switch.

2. Connect to the supply as detailed on the next page.

3. Select the Ramp test using the TEST TYPE key.

4. Select the RCD type using the TYPE key.

5. Press and hold the TEST button.

If the RCD trips, the first displayed result depends upon
the Setting selected.

RCD Rating Current Range Step Value

10mA 5..15mA 1mA

30mA 15..50mA 1mA
100mA 50..150mA 2mA
300mA 150..300mA 6mA
500mA 250..500mA 10mA

1000mA 500..1040mA 52mA

Setting A(Europe): The contact or fault voltage is
displayed with the Loop resistance, trip current and trip
resistance available by pressing the ENTER key.

Setting b (UK): The trip time is displayed with the trip
resistance, contact voltage and loop resistance available
by pressing the ENTER key.

The trip current and the trip resistance values are
displayed with the TEST TYPE symbol. The Trip
resistance is the fault required to trip the RCD.

Auto Sequence RCD Test
If the RCD is not located near a convenient installation

socket, it could mean walking back and forward
between the RCD and the instrument to reset the RCD
each time it trips out. To simplify and speed up
sequence testing, the instrument can be set to
automatically perform each subsequent test in the

21

Operation

sequence each time that the power is restored. This test
depends upon whether Setting Aor Setting b is
selected. The Overcurrent or Fast Trip is 150mAif
Setting b is selected, and 5 x I if Setting A is selected.
The display shows 150mA or 5I symbols as
appropriate.The test procedure is as follows:-

1. Connect to the supply as detailed on the next
page.

2. Select the RCD rated current on the rotary switch.

3. Select Auto RCD test sequence by pressing the
TEST TYPE key until the
symbols are displayed in sequence. Auto test is only
applicable to a.c. sensitive non delayed RCDs,
therefore TYPE segments are not displayed.

4. Press and release the TEST button.

5. Reset the RCD within 30 seconds after each trip
test.

6. Tests will be carried out in the sequence
180°, Fast Trip 0° and 180°. After each trip test, the
instrument will wait for up to 30 seconds for the
supply to be switched back on before continuing with
the next test. The test sequence will abort if any of
the tests fail, or if the RCD is not reset within the
time limit.

22

1

⁄2I; 0°; 180° and Fast trip

1

⁄2I, 0°,

On completion, the result of the last Fast trip test is
displayed. Press the ENTER key to sequentially
display:-

Supply voltage
Supply Frequency
Contact voltage
Earth Loop Resistance
0° trip test time
180° trip test time
0° Fast trip test time
180° Fast trip test time

All results can be stored under a single circuit reference.
See ‘Test Result Storage, Deletion and Retrieval’.

Connecting to the Supply

Automatic Testing

To aid rapid testing, the instruments can be set to
start a test automatically when connected to the
supply. This may be of use for example, when using
a clip and a probe. Select the range required and
press the test key without the supply present. The
instrument will display <100V for approximately
30 seconds. Apply the supply voltage within this time
and the instrument will pause before performing one
test automatically.

At a power socket
The simplest way of connecting to the installation is by

inserting the power plug into a convenient installation
socket. If Setting Ais selected when using the plug
terminated lead set, the polarity of the mains socket is
immaterial. Line and Neutral will be swapped if
necessary, and an indication given on the display.
Setting b requires Line and Neutral to be fixed.

1. Insert the power plug into an installation socket.

2. Select and set the rated current, RCD type and the
test type.

3. Supply voltage, configuration symbols and polarity
are displayed.

4. Press the TEST key.

5. See previous notes for type of test.

If desired the test can be repeated by pressing TEST
again.

Not at a power socket
If an installation socket is not available use the 3-wire

lead set

1. Connect the red lead to phase and the green lead to
earth. No connection to neutral is needed.

2. Select and set the rated current, RCD type and the
test type.

3. Supply voltage and polarity are displayed prior to the
test.

4. Press the TEST key.

5. See previous notes for type of test.

If desired the test can be repeated by pressing TEST
key again.

23

Operation

Error Numbers
In the unlikely event of a hardware or software fault or

error the display willshow an error number in the form
of a digital ‘E’ together with an identifying 2-digit
number.

If such an error number is displayed, switch the
instrument off and back on again. Then repeat the test
that was originally being carried out, or as given in the
following table.

If the error number is again displayed, switch the
instrument to off, and return the instrument to the
manufacturer for service, together with a description of
the events leading to the message display. See
‘Returning an Instrument for Repair’.

24

Error Number Appropriate Action

EEPROM failure.
Stored data is lost.
Attempt to delete the stored test
results and then store another
result. If error number persists,
return the instrument for service.

(Loop LE, LN or LL)
Secondary internal thermal cut­out is open circuit.
Return the instrument for service.

Possibly due to excessive ‘noise’
on the supply, or the RCD
unexpectedly trips together with
an internal fault. If error number
persists, return the instrument for
service.

Operation (LCB2500 only)

Saving Results (LCB2500 only)
After a test, the result is displayed on the screen and

this may be saved with additional information. Acircuit
number (1-99) may be assigned, and when moving site
or building, circuits may be grouped using the
distribution board feature. In this way, when
downloading to PC software such as AVO
or NICEone™, the results can be easily split into different
test schedules. When the results are displayed or
printed, a change in the distribution board is indicated.

Changing Distribution Boards (DB)
Before a test the distribution board number may be

changed as follows:

1. Move the rotary selector switch to the RCL position.
The code is displayed.

currently selected DB code is displayed, e.g. d01.

3. This number may be changed using the up and
down keys to display the required number.

4. The number can be accepted by pressing the SAVE
key, or the procedure aborted by pressing the EXITkey.

5. When the number is saved the code Std is displayed
(accompanied by a long bleep) to confirm that the
data has been saved.

Testing may now continue with all subsequent results
being stored associated with the new distribution board
number.

2. Press the SAVE key. The

®

PowerSuite

Saving a result
On completion and display of the measurement:

1. Press and hold the SAVE key. After about 1 second,
a bleep will be heard. For a (Loop) L-N test, a code,
as given in the following table is displayed. Acode is

™

used to describe the circuit tested and can
accordingly be modified by the user. For all other
tests, a circuit number code is displayed, and you
should proceed directly to step 4.

2. The code may be changed by pressing the up and
down keys

3. The code may be accepted by pressing the SAVE
key, or aborted by pressing the EXIT key.

4. The circuit number is displayed as 2 digits, e.g. c01.

Note: Many different tests may be saved under the

same circuit number.

5. The circuit number may be changed by pressing the
up and down keys to display an appropriate number.
Hold the key down to step through the circuit
numbers.

6. The number can be accepted and the results saved
by pressing the SAVE key, or the procedure aborted
by pressing the EXIT key.

7. When the result is saved, the code Std is displayed
(accompanied by a long bleep) to confirm that the
data has been saved. The display of FULL indicates
that there is no more test storage.

25

Operation (LCB2500 only)

Delete all data

1. Move the rotary selector switch to the RCL position.
The code is displayed.

2. Press the up and down keys

together. The code dELis displayed.

3. Confirm that the data is no longer required by
pressing the SAVE key or abort by pressing any
other key. The code is displayed.

Print Results

1. Connect printer and the instrument with a serial
printer lead.

2. Move the rotary selector switch to the RCL position.
The code is displayed.

3. Commence the printout by
pressing the TEST key. Abort at any time by
pressing and holding the ENTER key. The code

is displayed.
Printer Setup Mode
The instrument cannot respond to a busy signal given

by a printer, and therefore waits at the end of each line.
This wait time and the printer report language can be
changed.

1. Press and hold the BACKLIGHT key then turn the

rotary selector switch from the OFF position to the
RCL position. The code is displayed.

2. Release the

BACKLIGHT key.

To change the Printer wait time

26

1. Toggle the TEST TYPE key to scroll through and
display the code .

2. Press the ENTER

key. The current setting is displayed.

3. Toggle the up and down keys until the required
setting is displayed.

4. To save the new setting, press the SAVE key. The
bleeper sounds and STD is displayed. To abort the
new setting, press the EXIT key.

To select the printer language

1. Toggle the TEST TYPE key to scroll though and
display the code .

2. Press the SAVE key.
The current printer report language is displayed as 1
(English) or 2 (as given on the type label on the
User Guide cover). AVO Download Manager
supplied with your instrument enables the second
printer language to be changed. Refer to the
instructions supplied with the disk.

3. Toggle the TEST TYPE key until the required
language setting is displayed.

4. To save the new setting, press the SAVE key. The
bleeper sounds and STD is displayed. To abort the
new setting, press the EXIT key.

Retrieve Stored Results
It is possible to view previously stored test results as

follows:

1. Move the rotary selector switch to the RCL position.

The code is displayed.

2. Select the required distribution
board by pressing the up and down keys. The
distribution board numbers are shown in order that
the the results were stored. Hold a key down to
auto-repeat. Along bleep is sounded when the end
of the list is reached.

3. Press the ENTER key to list the circuit numbers
used in the currently displayed distribution board or
press the EXIT key to return to the RCL display

4. Select the required circuit number by pressing the
up and down keys. The circuit numbers are shown in
numerical order. Hold a key down to auto-repeat. A
long bleep is sounded when the end of the list is
reached.

Loop Test

RCD Test

5. Press the ENTER key to show the stored test codes
or press the EXIT key to return to the distribution
board selection screen.The following codes are used
to identify test results:-

6. Select the required test by pressing the up and
down keys. The tests are shown in the above order.
Hold a key down to auto-repeat. Along bleep is

sounded when the end of the list is reached.

7. Press the ENTER key to scroll through the stored
test results, together with any additional connection
information or press the EXIT key to return to the
circuit number selection screen.

Signal Installation PC

Tester 9-way ‘D’ 25-way ‘D’
Rx 2 3 2
Tx 3 2 3

DTR* 4 6

DSR 6 4 20
GND 5 5 7

Downloading to a PC
Normally, a double-ended 9-way ‘D’female socket lead

suitable for connecting PC to PC is required. This lead
should not exceed 3m in length. Alead is available as
an accessory, or one can be made up as follows:-

The CD-ROM supplied with the instrument includes AVO
Download Manager which will allow you to retrieve and
edit saved results, and export into other Microsoft

™

Windows
the disk for further information.

packages. Follow instructions supplied with

27

Operation (LCB2500 only)

To a serial printer for printing reports
Normally, a 9-way ‘D’female socket to a 25-way ‘D’

female socket lead suitable for connecting PC to printer
is required. This lead should not exceed 3m in length. A
lead is available as an optional accessory, or one can
be made up as follows:-

Signal LCB2500 Printer

25-way ‘D’

Tx 2 2
DSR 6 20
GND 5 7

28

To a serial printer for printing reports
The printer should be set to 9600 baud, 8 bits data, no

parity and 1 stop bit. This instrument uses a special
isolated serial interface which is powered from the PC or
printer. In the unlikely event that your PC or printer is
not able to power the interface, it will be necessary to
provide an additional supply. Contact AVO Product
Support for details.

Specifications

Supply Voltage Measurement

25-500V Intrinsic accuracy ±2% ±2 digits

Supply Frequency Measurement

d.c., 16-460Hz Intrinsic accuracy ±0,1% ±1 digit

Loop Resistance Measurement (to EN 61557-3)

Line/Earth Loop
Displayed Range: 0,01Ω to 3,00kΩ

Nominal Supply: 230V, 50Hz
EN61557
Operating Range: 0,25Ω to 3,00kΩ

Intrinsic accuracy:

0,01Ω-9,99Ω ±4% ±0,03Ω
10,0Ω-89,9Ω ±5% ±0,5Ω

90Ω-899Ω ±5% ±5Ω

900Ω-3,00Ω ±5% ±20Ω

Line-Line (Phase/Phase) Loop Resistance
measurement (to EN 61557-3)

Displayed Range: 0,01Ω to 19,99Ω
Intrinsic accuracy: ±5% ±0,03Ω
Nominal Supply: 230V, 50Hz
EN61557
Operating Range: 0,25Ω to 19,99Ω

Prospective Fault Current

Prospective fault current =

Measured Voltage Nominal Voltage

>150V 110V

150V-300V 230V

>300V 400V

Prospective Fault Current is calculated from the
respective loop resistance. Ranges and accuracies are
therefore derived from the previous section.

Nominal voltage

Loop resistance

Line Earth Loop Resistance Measurement at
15mA (to EN 61557-2)

Loop L-PE 0.1Ω
Displayed Range: 0,1Ω to 2,00kΩ
Intrinsic accuracy: up to 200Ω ±3% ±0,3Ω

Noise Immunity: 1σ of reading within 0,3Ω on a
Nominal Supply: 230V 50Hz

EN61557
Operating Range: 5,0Ω to 2,00kΩ

Loop L-PE 0.01Ω
Displayed Range: 0,01Ω to 10,00Ω
Intrinsic accuracy: ±5% ±0,05Ω

over 200Ω ±5% ±5Ω
normal domestic supply

29

Specifications

Noise Immunity: 1σ of reading within 0,05Ω on a
Nominal Supply: 230V 50Hz

EN61557
Operating Range: 0,5Ω to 10,00Ω

RCD Testing

Selectable Ranges: 30mA, 100mA, 300mA,

Test Facilities: Contact voltage tests at

RCD Types: General purpose, delayed
Nominal Supply: 230V, 50Hz

Supply Range: 100-280V, 45-65Hz
Note: The maximum possible test current (including the

5I multiplier) is 1000mA/300mA for d.c. sensitive
RCDs. These limits are halved if the supply
voltage is less than 200V.

1

⁄2I∆n Test

Contact Voltage
Displayed range: 0V to 90V
Measurement range: 5V to 90V
Intrinsic error: +5%/+15%±0.5V

30

normal domestic supply

(to EN61557-6 up to 500mA)

500mA, 1000mA
Variable 10mAto 1000mA

Loop resistance tests at
No Trip tests at

1

⁄2I∆n
Trip tests at I∆n, 5I∆n
Fast Trip test at 150mA
Ramp tests

(Selective) and d.c. Sensitive

1

⁄2I∆n

1

⁄2I∆n

Loop resistance (measured at

1

⁄2I∆n)

I∆n Resolution

10 0,5Ω to 9kΩ

30 170Ω to 3kΩ
100 50Ω to 900Ω
300 17Ω to 300Ω
500 10Ω to 180Ω

1000 5Ω to 90Ω

2 second No Trip test at

1

⁄2I∆n (optional)
The test current flows for 2 seconds. Atripped RCD will
result in a display of <1999ms

Intrinsic Test Current accuracy: -8% to -2%

Trip Tests

I∆n Trip Test
This test will perform a short automatic
followed by a 30 second delay (Selective type only) then
execute a Trip test.

General purpose Test I∆n test for up to 300ms
Selective Test I∆n test for up to 2000ms

Timed Trip Tests
Trip time displayed Range

Intrinsic Trip time accuracy ±1% ±1ms

1

⁄2I∆n test,

0,1ms to test time limit

Intrinsic Test Current accuracy +2% to +8%

Ramp Test (Trip current measurement)

1

This test will perform an automatic
a 30 second delay (Selective type RCD only) and then
execute an incremental ramp test.

Intrinsic Ramp Test Current accuracy ±3%

I∆n Ramp Range Increment

10 5-15mA 1mA

30 15-50mA 1mA
100 50-150mA 2mA
300 150-300mA 6mA
500 250-500mA 10mA

1000 500-1020mA 52mA

⁄2I∆n test followed by

150mA 40ms Trip Test

This is a stand alone test at 150mA for 40ms
Displayed Range 0,1ms to 40ms
There is no associated

1

⁄2I∆n test or Delay.

Power Supply

6 x 1,5V Alkaline cells type LR6 or 1,5V nickel cadmium

rechargeable cells.

Fuses

Non replaceable 2 x 7A(SIBA 70-065-63)
The 7A fuses protect the instrument and are not
replaceable by the user.

Safety

Meets the requirements for double insulation to
IEC61010-1 (1995), EN61010-1 (1995) Installation
Category III***, up to 230V to earth and 400V phase to
phase, without the need for separately fused test leads.
If required, fused test leads are available as an optional
accessory.

Complies with the relevant parts of EN 61557:1997-02
as detailed below.

*** Relates to the transient overvoltages likely to be met
in fixed wiring installations.

E.M.C. Meets EN61326-1 (1997)

Environmental Protection

IP54 The instrument is designed for

indoor and outdoor use.
Temperature Range
Operating -5°C to +40°C up to 90% RH

Storage -25°C to +65°C up to 90% RH

31

Specifications

General

Dimensions 230mm x 114mm x 62mm
Weight 920g with battery but without

Cleaning Wipe the disconnected

IEC 61557/EN 61557

Complies with the following parts of EN 61557,
Electrical safety in low voltage systems up to 1000V a.c.
and 1500 V d.c. – Equipment for testing, measuring or
monitoring of protective measures:-

Part 1 - General requirements
Part 3 - Loop resistance
Part 6 - Residual current devices (RCDs)

32

leads and test & carry case

instrument with a clean cloth
dampened with soapy water or
Isopropyl Alcohol (IPA).

Accessories

Part Number

Test and carry case Holds, and supports the instrument to allow ‘hands free’

Pouch Holds and protects the instrument when not in use. 6420-121
Carrying strap Attaches to case or instrument. 6220-611
2-wire Test lead set With prods and clips. 6231-631
3-wire test lead For three phase sequence testing, including 2 prods and 3 clips. 6231-632
U.K. Mains plug test lead Fitted with BS1363 fused plug. 6231-633
Euro Mains plug test lead Fitted with CEE7/7 plug. 6231-635
U.K. Earth bond test lead Fitted with BS1363 fused plug. 6231-634
Switch Probe SP2 2-wire lead set with a ‘Test’ key in the black probe. 6231-636
2-wire test lead set (5m) 2 wire lead set with 5m long leads. 6231-637
Fused probe and clip set Replace normal probes and clips supplied with 2- and 3-wire test

Computer Serial lead To connect the instrument to PC with 9-way ‘D’ connector, 1,8m long. 25955-025
Printer serial lead To connect the instrument to serial printer, with 25-way ‘D’ socket 25955-026
Download Manager Installation Tester Setup and simple download software 6111-442
AVO

AVO

®

PowerSuite

®

NICEone

™

™

operation in use, and protection when not in use. 6420-114

(2 probes and 3 clips) test lead kits. 600V max. 10A fuse. 6180-405

Windows™program for Installation Testing
Certificate generation etc. Contact Distributor

Windows™program for Installation Testing certificate generation etc. 6111-403

33

Publications

User Guide
‘Testing Electrical Installations’ Adetailed account of how to carry out practical testing to

‘A Stitch in Time’ The complete guide to electrical installation testing. AVTM21-P8B
‘Getting Down to Earth’ A practical manual on earth resistance testing. AVTB25-TA

†

Available in several languages. Please contact your local distributor for availability.

†

BS 7671 (16th Edition IEEE Wiring Regulations). 6172-129

34

Part Number

6172-428

Loop Resistance Tables

Limit

Min.

Limit

Min.

Limit

Min.

indicated

reading

17,0
21,5
26,0
30,5
35,0
44,0
53,0
62,0
71,0
80,0
89,0

125
170
215

Limit

300
350
400
450
500
600
700
800

900
1,00
1,50
2,00
2,50
3,00

0,10
0,15
0,20
0,25
0,30
0,35
0,40
0,45
0,50
0,60
0,70
0,80
0,90
1,00

indicated

reading

0,03
0,08
0,12
0,17
0,21
0,26
0,30
0,35
0,39
0,48
0,57
0,66
0,75
0,84

1,50
2,00
2,50
3,00
3,50
4,00
4,50
5,00
6,00
7,00
8,00
9,00

10.0
15,0

indicated

reading

1,29
1,74
2,19
2,64
3,09
3,54
3,99
4,44
5,34
6,24
7,14
8,04
8,94
12,5

20,0
25,0
30,0
35,0
40,0
50,0
60,0
70,0
80,0
60,0

100
150
200
250

Loop Resistance L-N/L-PE/L-L

Use these tables to determine the lowest allowed
reading for a limit, taking into account the maximum
service error of the instrument.

Min.

indicated

reading

260
305
350
395
440
530
620
710
800
0,86
1,31
1,76
2,21
2,66

Limit

Min.

Limit

3,0
3,5
4,0
4,5
5,0
6,0
7,0
8,0

9,0
10,0
15,0
20,0
25,0
30,0
35,0
40,0
45,0
50,0
60,0

indicated

reading

1,2
1,7
2,2
2,6
3,1
4,0
5,0
5,9
6,9

7,8
12,5
17,2
21,9
26,6
31,3
36,0
40,7
45,4
54,8

70,0
80,0
90,0

100
150
200
250
300
350
400
450
500
600
700
800

900
1,00k
1,50k
2,00k

Min.

indicated

reading

64,2
73,6
83,0
92,4
139
183
230
277
324
371
418
465
559
653
747
841

935
1,41k
2,00k

Loop Resistance L-PE 0.1Ω

35

Repair and Warranty

The instrument circuit contains static sensitive devices,
and care must be taken in handling the printed circuit
board. If the protection of an instrument has been
impaired it should not be used, and be sent for repair by
suitably trained and qualified personnel. The protection
is likely to be impaired if, for example, the instrument
shows visible damage, fails to perform the intended
measurements, has been subjected to prolonged
storage under unfavourable conditions, or has been
exposed to severe transport stresses.

New instruments are guaranteed for 3 year period from
the date of purchase by the user.

Note: Any unauthorised prior repair or adjustment will

automatically invalidate the Warranty.

Instrument Repair and Spare Parts

For service requirements for MEGGER®Instruments
contact:-

AVO INTERNATIONAL or AVO INTERNATIONAL
Archcliffe Road Valley Forge Corporate Center
Dover 2621 Van Buren Avenue
Kent, CT17 9EN. Norristown, PA 19403
England. U.S.A.
Tel: [phone] Tel: [phone]
Fax: [phone] Fax:[phone]

or an approved repair company.

36

Approved Repair Companies

A number of independent instrument repair companies
have been approved for repair work on most MEGGER
instruments, using genuine MEGGER®spare parts.
Consult the Appointed Distributor/Agent regarding spare
parts, repair facilities and advice on the best course of
action to take.

Returning an Instrument for Repair

If returning an instrument to the manufacturer for repair,
it should be sent freight pre-paid to the appropriate
address. Acopy of the Invoice and of the packing note
should be sent simultaneously by airmail to expedite
clearance through Customs. Arepair estimate showing
freight return and other charges will be submitted to the
sender, if required, before work on the instrument
commences.

®

37383940414243

AVO INTERNATIONAL

Archcliffe Road PO Box 4651 S. Westmoreland Road MEGGER SA,
Dover Valley Forge Dallas 29 Allée de Villemomble
Kent, CT17 9EN. PA 19484-9007 TX 75237-1017 93340 Le Raincy
England. U.S.A. U.S.A. Paris, France
Tel: [phone] Tel: [phone] Tel: [phone] (U.S.A. only) Tel: [phone]
Fax: [phone] Fax: [phone] Tel: [phone] (International) Fax: [phone]

This instrument is manufactured in the United Kingdom.
The company reserves the right to change the specification or design without prior notice.

MEGGER is the registered Trade Mark of AVOINTERNATIONAL LIMITED. Copyright © AVO INTERNATIONALLIMITED
Part No 6172-428 – Edition 1 – Printed in England – 12EE

Fax: [phone] Fax: [phone]