Megger MIT30 User manual

AVTMMIT30-EN
Rev E02
June 2009
Instruction Manual
-30kV DC Insulation Tester
MIT30
Catalog No. MIT30
High Voltage Equipment
THIS EQUIPMENT PRODUCES
INSTANTANEOUSLY LETHAL VOLTAGE
Please read carefully before operating
Safety is the responsibility of the user
M
Valley Forge Corporate Center
2621 Van Buren Avenue
Norristown, PA 19403-2329
U.S.A.
610-676-8500
www.megger.com

-30kV DC Insulation Tester
MIT30
Catalog No. MIT30
Instruction Manual

Copyright© 2009 by Megger. All rights reserved.
The information presented in this manual is believed to
be adequate for the intended use of the product. If the
product or its individual instruments are used for
purposes other than those specified herein, confirmation
of their validity and suitability must be obtained from
Megger. Refer to the warranty information below.
Specifications are subject to change without notice.
WARRANTY
Products supplied by Megger are warranted against
defects in material and workmanship for a period of 12
months following shipment. Our liability is specifically
limited to replacing or repairing, at our option, defective
equipment. Equipment returned to the factory for repair
must be shipped prepaid and insured. Contact your
MEGGER representative for instructions and a return
authorization (RA) number. Please indicate all pertinent
information, including problem symptoms. Also specify
the serial number and the catalog number of the unit.
This warranty does not include batteries, lamps or other
expendable items, where the original manufacturer’s
warranty shall apply. We make no other warranty. The
warranty is void in the event of abuse (failure to follow
recommended operating procedures) or failure by the
customer to perform specific maintenance as indicated in
this manual.
M
Valley Forge Corporate Center
2621 Van Buren Avenue
Norristown, PA 19403-2329
U.S.A.
610-676-8500
www.megger.com

AVTMMIT30-EN Rev E02 June 2009
i
Table of Contents
1 INTRODUCTION ...........................................................1
How to Use this Manual....................................................1
2 SAFETY PRECAUTIONS..............................................3
3 RECEIVING INSTRUCTIONS....................................7
4 SPECIFICATIONS...........................................................9
Input.....................................................................................9
Output..................................................................................9
Control...............................................................................10
Safety ..................................................................................11
Physical ..............................................................................11
Environmental ..................................................................12
Regulatory Compliance....................................................12
5 DESCRIPTION...............................................................13
6 SETTING UP...................................................................15
Selection of Location .......................................................15
Clearances..........................................................................16
Connections Procedure ...................................................17
7 OPERATION ..................................................................19
TEST PROCEDURE .....................................................19
USE OF GUARD............................................................21
8 ROUTINE MAINTENANCE .....................................23
Before Each Use...............................................................23
Inspection and Maintenance Procedure........................24
Calibration Procedure......................................................25
9 THEORY OF OPERATION &
TROUBLESHOOTING ................................................29
10 NOMENCLATURE.....................................................33
Field Replaceable and Recommended Spare Parts......33

AVTMMIT30-EN Rev E02 June 2009
ii
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AVTMMIT30-EN Rev E02 June 2009
1
1
INTRODUCTION
This instruction manual is intended as a guide to
the operation of the MIT30. The instructions and
suggestions provided in his manual anticipate the
normal use of the insulation tester for testing
electrical insulation systems.
In the normal course of testing, a specimen or
system is subjected to high DC voltage. The
resulting current and the manner in which the
current varies with time, provides data that
indicates the condition of the specimen or system
insulation.
How to Use this Manual
Typographic Conventions
Numbered lists show procedural steps.
Bullets list items and options.
Warning and Caution Notices
Warning and caution notices are used throughout
this manual where applicable. These notices

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AVTMMIT30-EN Rev E02 June 2009
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appear in the format shown below and are
defined as follows:
WARNING!
Warning, as used in this manual,
is defined as a condition or
practice which could result in
personal injury or loss of life.
CAUTION
Caution, as used in this manual,
is defined as a condition or
practice which could result in
damage to or destruction of the
equipment or apparatus under
test.
NOTES: Provide important information

AVTMMIT30-EN Rev E02 June 2009
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2
SAFETY PRECAUTIONS
SAFETY IS THE RESPONSIBILTY OF THE
USER
The test set and the equipment to which it is
connected is a source of high-voltage electrical
energy. All persons performing or assisting in the
tests must use all practical safety precautions to
prevent contact with energized parts of the test
equipment and associated circuits. Persons
actually engaged in the test must stand clear of all
parts of the complete high voltage circuit unless
the test set is de-energized and all parts of the test
circuit are grounded. Persons not directly
associated with the work must be kept away from
the test activities by suitable barriers, barricades or
warnings.
The test set must be connected to a reliable local
ground to prevent possible shock danger to the
operator. Since the energized test setup may
induce a static charge on nearby insulated objects,
including people, all insulated objects must be
grounded or kept at least three feet (0.91 meters)
from the energized structure.

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AVTMMIT30-EN Rev E02 June 2009
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WARNING
Never connect the test set to
energized equipment or use the
test set in an explosive
atmosphere.
All apparatus to be tested should be bonded to
ground except during the actual test. Test
connections should be made with the ground
bonds in place.
NOTE: Please note that even isolated conductors may
develop static charge due to nearby electrical
fields.
At the completion of a test, after the power
source has been shut down and the test set kV
meter reads zero, all energized parts of the test
setup MUST be short circuited by means of a
safety grounding/discharge rod or “hot stick.”
Ground bonds should then be applied to the
equipment that was tested. These should be left in
place until access to the equipment is again
required.
If the test set is operated in accordance with the
safety precautions noted above and if all grounds
are correctly made, rubber gloves are not
necessary. That being so stated, please observe all
governmental, local, work regulations as
applicable with regard to operating or working in
proximity to high voltage electrical energy. Ensure
the use of all PPE (Personal Protective