Megger S1-1054/2, S1-1052/2 User Manual

M

S1-1054/2
10kV Digital Insulation Tester

USER MANUAL

GSAFETY WARNINGS

Safety Warning must be observed during use.

n

The circuit under test must be switched off, de-energised, isolated and checked to be safe before insulation test connections are made. Make sure

the circuit is not re-energised whilst the instrument is connected.

n

Circuit connections must not be touched during an insulation test.

n

After completing a test, capacitive circuits must be completely discharged before disconnecting the test leads. Capacitive charges can be lethal.

n

Tested items should be firmly shorted out with a shorting link, after discharge, until required for use. This is to guard against any stored dielectric

absorption charge subsequently being released thereby raising the voltage to potentially dangerous levels.

n

The voltage indicator and automatic discharge features should be regarded as additional safety features and not a substitute for normal safe working

practice.

n

It is rare, but in certain circumstances, breakdown of the circuit under test may cause the instrument to terminate the test in an uncontrolled manner,

possibly causing a loss of display while the circuit remains energised. In this event, the unit must be turned off and the circuit discharged manually.

n

Test leads, including crocodile clips, must be in good order, clean and with no broken or cracked insulation.

n

The instrument should not be used if any part of it is damaged.

n

Insulation testing in wet weather conditions might be hazardous. It is recommeded that this instrument is not used in these circumstances. If this

unavoidable, the user must take all necessary precautions.

n

This instrument is not intrinsically safe and must not be used in hazardous atmospheres.

2

NOTE

THE INSTRUMENT MUST ONLY BE USED BY SUITABLY TRAINED AND COMPETENT PERSONS.

Users of this equipment and/or their employers are reminded that National Health and Safety Legislation requires them to carry out valid risk
assessments of all electrical work so as to identify potential sources of electrical danger and risk of electrical injury such as inadvertent short circuits.
Where the assessments show that the risk is significant then the use of fused test leads may be appropriate.

CAT II

Measurement category II: Equipment
connected between the electrical outlets and
the user’s equipment.

CAT III

Measurement category III: Equipment
connected between the distribution panel and
the electrical outlets.

CAT IV

Measurement category IV: Equipment connected
between the origin of the low-voltage mains
supply and the distribution panel.

Test mode summary 16
Insulation resistance ‘IR’ test 16
Breakdown mode / burn mode 16
Alarm limit mode 16
Step voltage ‘SV’ test 17
Polarisation index ‘PI’ test, and dielectric absorption
ratio ‘DAR’ test 17
Dielectric discharge ‘DD’ test 17
Measurements above 100 GΩ 18
Circuit block diagram 19
Specifications 21
Accessories 22
Repair and warranty 23

Battery replacement 23

Symbols used on the instrument are:

F Caution: risk of electric shock
G Caution: refer to accompanying notes

t Equipment protected throughout by Double

Insulation (Class II)

c Equipment complies with current EU directives.

This equipment should be recyled as electronic
waste.

Terms used in this manual
The word must is used to indicate that the instructions following should
be followed under all circumstances. Failure to follow these instructions
could result in damage to the instrument and / or a hazard to the
operator. The word should is used to indicate that the instructions
indicate best practice.

CONTENTS

3

Safety warnings 2
Introduction 4
General description 4
Features 4
Cleaning 5
Power lead and battery charging 5
Instrument controls and indicators 6
Power On/Off button 7
Test voltage s and t buttons 7
Test start / stop button 7
Ω/I button 7
B button 10
Fn button 10
Mode button 10
Timer s and t buttons 11
Record button 11
Recording to on-board memory 11
Downloading results 11
Deleting results 11
Recording to a PC 12
High voltage warning LED 12
Line input present LED 12
Test terminals 12
Guard terminal 12
RS232 / USB connections 13
Battery bar graph 13
Voltage at terminals 13
Timer indicator 13
Digital display 13
Analogue display 14
Secondary display 14
Pre-Test / during test key action table 14
Breakdown detection 15
Noise detection 15

A comprehensive LCD display shows resistance, current, filter setting,
capacitance, time constant, voltage, timer measurements, and figure of
merit measurements such as polarisation index.

Features

n Continuous resistance or current measurement on main display.

n Optional resistance, current, or figure of merit measurements on

secondary display.

n Standard test voltages – 250 V, 500 V, 1 kV, 2.5 kV, 5 kV, 10 kV

n Non-standard test voltages – selectable between 50 V and 1 kV in 10

V steps, and selectable between 1 kV and 10 kV in
25 V steps.

n Test modes include insulation resistance, polarisation index, step

voltage and dielectric discharge.

n 4 mA rms hardware noise current filter (selectable)

n Firmware filter 10, 30, and 100 seconds (optional)

n The dielectric absorption ratio is automatically calculated if the

corresponding timers are set.

n Either burn or breakdown selectable in insulation resistance mode.

n Insulation ‘Alarm Limit’ available in insulation resistance mode.

n Programmable timers include a main test duration timer, plus T1 and

T2 timers for time resistance method type tests.

n Load capacitance and time constant measurements – displayed at end

of test.

n LCD backlight.

n Data storage, data retrieval and real time data output.

n USB or RS232 communications.

n Battery level / charge level indicator.

INTRODUCTION

4

General Description

The S1-1054/2 is a microprocessor controlled 10 kV insulation tester
offering measurement capability of up to 35 TΩ. The instrument
performs automatic tests and has data storage and data retrieval facilities.

Polarization index and dielectric discharge tests are performed
automatically, and test duration and voltages can be adjusted according
to user preference for these tests. A step voltage test can be performed
automatically, with a default voltage of 1 kV, and test duration of 5
minutes. It is possible for the user to set different voltages and test
durations for the step voltage test.

The S1-1054/2 incorporates a hardware filter designed to tolerate at
least 4 mA rms of noise current at 50Hz and above. This filter is enabled
by default, but may be switched off in order to speed up the settling
time when there is little noise current. The Insulation Resistance mode
offers additional firmware filtering to average out slow variations during
testing.

The S1-1054/2 can be powered from the mains supply or by its own
internal rechargeable battery, which provides for at least 4 hours of
continuous testing with a 100 MΩ load. A battery level indicator on
the LCD display indicates battery capacity. Connecting power to the
mains supply connector will automatically charge the battery whether
the instrument is switched ‘on’ or ‘off’, except during testing. A high
level of internal isolation allows the instrument to be used while the
unit is supplied from the mains. An internal battery management system
switches the instrument off after ten minutes of inactivity. If the battery
approaches a very low state of charge the instrument turns itself off, and
mains power must be applied before the instrument can be used again.
Recorded test results and settings will not be lost when the instrument is
switched off.

If the power lead supplied is not suitable for your mains connection,
do not use an adaptor. Always use a power lead fitted with the correct
plug.

The instrument is fitted with a two-pin IEC60320 power inlet. Most
power leads are made with three-core cable, so the ground connection
will not be used.

Power lead connection table

Connection UK/International USA

Earth/Ground Yellow/Green Green

Neutral Blue White

Live (Line) Brown Black

If using a fused plug, ensure that it is fitted with a 3 Amp fuse.

The instrument can be powered from 85 - 265 Vrms a.c. at 50/60 Hz.
The battery will charge as long as the mains supply is connected, except
when a test is in progress. The power On/Off button has a green LED,
which illuminates when mains power is present. For optimum battery
life, charge the battery after each use. A completely exhausted battery
will take 14 hours to recharge.

POWER LEAD AND BATTERY CHARGING

5

Cleaning

Disconnect the instrument and wipe it with a clean cloth slightly
damped with soapy water or Isopropyl alcohol (IPA).

INSTRUMENT CONTROLS AND INDICATORS

6

Measurement terminals

-ve guard +ve

RS232

USB

Line

input

Time s and
t selectors

Voltage s
t selectors

Line input
Present
indicator

Power on/off

Ω/I selector

Burn indicator

Alarm

Data recording

Test modes

Voltage at
terminals

Battery level

Breakdown
indicator

High voltage
warning
indicator

High
voltage
warning
indicator

Analogue
display

Timers
Main, T1,
T2

Dielectric
absorption
ratio/T1 timer

Digital
display

Polarisation
index/timer
T2

Time
constant

Capacitance
display

Data record

High voltage
warning indicator

Test start/stop

ModeFunction

Backlight
on/off

S1-554

7

During a test the display shows the actual voltage on the test leads. If
the test voltage is changed during a test, the new test voltage will be
displayed briefly.

When the test has stopped, the display continues to show the voltage
present on the test leads. Pressing either test voltage s or t button will
then display the test voltage immediately before the end of the test.

Test start / stop button

A test will only start if this button is pressed, held and then released as
soon as the red high voltage warning indicator LED lights. The LCD and
red LED high voltage warning indicators flash when the test starts.

A test will not start if the button is released before the red LED shows,
or pressed continuously for longer than 5 seconds. This is a safety
feature to prevent a test being started inadvertently.

The presence of a voltage greater than 50 V on the test leads is indicated
with flashing high voltage warning indicators. Testing is disabled if the
external voltage exceeds 160 V.

Testing will stop if the test start / stop button is pressed again, the
preset test time is reached, or, if the unit is not in burn mode, insulation
breakdown is detected.

When a test has finished, the instrument will discharge the load, which
may take some time. The operator must always check the load has been
discharged before touching the test leads.

Ω/I button

Pressing this button toggles the digital and secondary displays. The

Power On/Off button

The instrument will only turn on if this button is pressed, held and then
released when the display responds. The instrument will not turn on if
the button is released before the display responds, or if the button is
held down for too long. This is a safety feature to prevent the instrument
being inadvertently turned on.

The instrument is turned off either by pressing the button again, or if the
instrument is running on the battery, by timing out after 10 minutes of
inactivity.

Upon switching the instrument on the display will first show ‘Ini’ while it
undergoes a self-checking routine. When Ini disappears, the instrument is
ready for use.

Test voltage s and t buttons
Using these buttons one of six test voltages can be selected: 250 V, 500
V,
1 kV, 2.5 kV, 5 kV, and 10 kV. The selected voltage is shown on the
display.

A non standard voltage between 50 V and 10 kV can be selected by
holding down the ‘Fn’ function button whilst operating the buttons. The
selectable voltage is adjustable in 10 V steps between 50 V and 1 kV, and
adjustable in 25 V steps between 1 kV and 10 kV. An auto repeat facility
is enabled when the button is held down, allowing faster travel through
the range.

If there is an external voltage greater than 50 V on the test leads, the
high voltage warning indicators are flashed, and the display shows this
voltage instead. The instrument will not perform a test if this voltage is
greater than 160 V.

8

Figure 1 - The result of an insulation resistance test (IR)

Test settings: T1 and T2 times set in order to measure the DAR
Test conditions: test runs for longer than 10 minutes as this is required
for a PI reading.

details available when scrolling the secondary display will depend upon
the test mode selected, whether timers T1 and T2 have been set, and
the duration of the test. The digital display toggles between insulation
resistance and current.

In the ‘IR’, ‘PI’, and ‘DD’ modes the secondary display initially shows the
PI (polarity index), DAR (dielectric absorption ratio), and, on completion
of the test, the TC (time constant) and capacitance measurements.
Further presses of the Ω/I button cycles the display through insulation
resistances, currents, and the filter setting.

In the ‘SV’ (step voltage) mode, the secondary display cycles through
insulation resistances, currents, and the filter setting.

Figures 1 to 4 illustrate the display status for sequential ‘Ω/I’ key presses
in the different modes.

Press Ω/I

Press Ω/I

Press Ω/I

Press Ω/I