Introduction; General Description; Features; Cleaning - Megger MIT520/2 User Manual

INTRODUCTION

General Description

The MIT520/2 is a microprocessor controlled 5 kV insulation tester offering
measurement capability of up to 15 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 MIT520/2 can be powered from the mains supply or by its own
internal rechargeable battery, which provides for at least 6 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.
A comprehensive LCD display shows resistance, current, capacitance, time
constant, voltage, timer measurements, and figure of merit measurements
such as polarisation index.
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Features

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Continuous resistance or current measurement on main display.
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Optional resistance, current, or figure of merit measurements on
secondary display.
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Standard test voltages – 250 V , 500 V , 1 kV , 2.5 kV , 5 kV
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Non-standard test voltages – selectable between 50 V and 1 kV in 10 V
steps, and selectable between 1 kV and 5 kV in 25 V steps.
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Test modes include insulation resistance, polarisation index, step
voltage and dielectric discharge.
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The dielectric absorption ratio is automatically calculated if the
corresponding timers are set.
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Either burn or breakdown selectable in insulation resistance mode.
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Insulation 'Alarm Limit' available in insulation resistance mode.
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Programmable timers include a main test duration timer, plus T1 and
T2 timers for time resistance method type tests.
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Load capacitance and time constant measurements – displayed at end
of test.
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LCD backlight.
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Data storage, data retrieval and real time data output.
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USB or RS232 communications.
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Battery level / charge level indicator.

Cleaning

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