Megger MIT510/2 Instruction Manual

MIT510/2
5kV Digital Insulation Tester

USER MANUAL

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GSAFETY WARNINGS

Safety Warning must be observed during use.

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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.

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Circuit connections must not be touched during an insulation test.

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

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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.

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

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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

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

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

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Insulation testing in wet weather conditions might be hazardous. It is recommended that this instrument is not used in these circumstances. If this is
unavoidable, the user must take all necessary precautions.

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

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.

must be turned off and the circuit discharged manually.

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CONTENTS

Safety warnings 2
Cleaning 3
Introduction 4
Power lead and charging 4
Instrument controls and indicators 5

Power On/Off button 6
Test voltage s and t buttons 6
Test start/stop button 6
Ω/I button 6

B button 6

High voltage warning LED 6
Line input present LED 7
Test terminals 7
Guard terminal 7
Factory programming socket 7
Battery bar graph 8
Voltage at terminals 8
Timer indicator 8
Digital display 8
Analogue display 8
Capacitance display 9
Time constant 9

Measurements above 100 GΩ
Circuit block diagram 10
Specification 10
Accessories 12
Repair and Warranty 13

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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.

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
practice.

Cleaning

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

should is used to indicate that the instructions indicate best

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INTRODUCTION POWER LEAD AND CHARGING

The MIT510/2 is a compact microprocessor controlled high voltage d.c.
insulation tester, powered by internal rechargeable battery or mains
supply. A comprehensive LCD display shows resistance, current,
capacitance, voltage and timer measurements digitally, with resistance
being shown in analogue as well.

Features include:

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Resistance or current measurement- front panel selectable

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Resistance measurement range - 10 kΩ to 15 TΩ

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Front panel selectable test voltages - 250 V, 500 V, 1000 V, 2500 V, 5000 V

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Incremental timer (minutes & seconds) – measures during test

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Load capacitance measurement – displayed at end of a test

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LCD backlight – front panel selectable

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Battery level/charging indicator

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Mains (line) input presence LED

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High voltage warning flashing LED shows when greater than 50 V
present on test leads

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High voltage warning LCD "flash" shows when greater than 50 V
present on test leads

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8 hours continuous testing on full charge.

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

NB: A plug severed from the power lead is a hazard if plugged into a live
socket. Severed plugs must be destroyed immediately.

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 cable colour coding:

International USA

Earth/Ground Yellow/Green Green

Neutral Blue White

Live (Line) Brown Black

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

The instrument can be powered from 95 - 240 V rms, ±10% 50/60Hz.
With power connected the battery will charge as long as a test is not in
progress. The

Power On/Off button has a green LED which illuminates

when mains power is present.

For best battery lifetime, charge the battery after each use. A completely
exhausted battery will take 14 hours to recharge.

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INSTRUMENT CONTROLS AND INDICATORS

1. Check connections to load - see SAFETY WARNINGS

2. To turn on, press Power On/Off button and release after display
responds. The instrument first will perform a self-check during which
Ini is displayed. After Ini disappears the instrument is ready for use.

3. Check voltage at terminals display to be sure the load is safe to
energise.

4. Set test voltage required with V

5. To start a test, press

TEST button and release after red LED shows. If

s and Vt buttons.

external voltage at terminals <50 V, testing starts.

6.

TEST button red LED and display warning symbols will flash during a
test to show high voltage present at terminals.

7. Timer will count up from zero during test.

Voltage at terminals

Battery level

Warning
voltage at
terminals

Digital
display

Time constant

Timer

Analogue
display

Warning
voltage at
terminals

Capacitance display

8. To stop the test press TEST button.

9. Timer will stop.

10. Analogue display shows insulation resistance.

11. Digital display shows resistance or current selected by pressing Ω/I

button.

12. Load capacitance will be calculated and displayed after the end of
the test.

13. Time-constant will be displayed after the end of the test.

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