MIT515, MIT525, MIT1025

5-kV and 10-kV Insulation Resistance Testers

n Industry best guard terminal accuracy

n Compact and lightweight for easy

transport and use

 PI, DAR, DD, SV and ramp test

 Unique dual case design provides

additional user protection

 Lithium-ion battery - extended capacity,

The new range of insulation resistance testers consists of

three models: two 5 kV units (MIT515 and MIT525) and a

10 kV unit (MIT1025). Resistance measurement is available

up to 10 TΩ for the 5 kV models and 20 TΩ for the 10 kV

model. The new instruments are smaller and lighter than

previous models yet offer advanced features and rapid

charge capability.

A key productivity feature is the ability to take

measurements when connected to line power/mains with

a dead battery. Intelligent battery charging ensures the

access. IP rating is IP65 with the case closed preventing

water/dust ingress. High reliability and safety are built in;

all models are safety rated to CATIV 600 V and are double

Five preset voltage ranges are provided in insulation

test mode, plus a user settable lock voltage range. Any

selectable test voltage may be locked and restored

via the selector switch, thereby increasing efficiency

of commissioning and repetitive tests. Preconfigured

diagnostic tests include Polarization Index (PI), Dielectric

to detect otherwise. Small defects can be easily detected

without risking the sudden large voltage increments

produced by a Step Voltage test. Monitoring the developing

graph during test enables the operator to terminate prior

to breakdown, thereby reducing the possibility of damage

to already flawed insulation. These units are particularly

informative on polyester, asphalt and epoxy-mica

insulations. They can also test voltage suppression devices.

Simplicity of operation is achieved with two rotary switches

and the large backlit display enables multiple results to be

Typical end users include:

 Testing and service companies

 Wind farm and solar generation operators

 Power generation and distribution companies

 Industrial companies

 Rail companies

regulations technology ensures maximum transfer

The units are designed for testing the insulation of high-

voltage electric equipment. Their wide voltage range

also allows applications for low-voltage equipment.

Generators, motors, transformers, cables and switchgear all

require effective maintenance. The test techniques on the

instruments provide valuable diagnostic information.

All three instruments test the insulation resistance of:

With its higher voltage testing capability, the MIT1025 is the

perfect everyday work tool for manufacturers, users and

maintainers of rotating machinery. Designed in accordance

with the requirements of IEEE43:2000, the MIT1025 is ideal

for measuring the insulation resistance of armature and

field windings in rotating machines rated 1hp (750 W) or

long-term trending of higher value apparatus.

protection while maintaining ruggedness.

regulations of IEC 61010-31:2008 while ensuring

measurement accuracy.

diagnostic testing capability.

(charges while operating).

highest accuracy of measured values.

when connected to the internet. No tedious and

potentially interruptive setup procedures.

frequency measurement allows the user to check for

induced voltages.

safe use in the widest range of applications.

MIT515, MIT525, MIT1025

5-kV and 10-kV dc Insulation Resistance Testers

What is the IEEE Standard 43-2000?

In March 2000, the IEEE-SA Standards Board approved

a revision of IEEE Std 43-1974 by the Electric Machinery

Committee of the IEEE Power Engineering Society. This

revision is IEEE Std 43-2000, the “IEEE Recommended

Practice for Testing Insulation Resistance of Rotating

Machinery.” Following is a brief summary of its highlights:

n Test voltages up to 10 kV are recommended for

Fig. 1: Quality insulation testers exhibit fast voltage rise

times to resistance levels commensurate with minimum

acceptable values, and maintain selected voltage

throughout the remaining measurement range. Below an

acceptable level of resistance, rapid voltage drop protects

the test item from exposure to high voltage, so that it may

be reclaimed by appropriate maintenance.

5.0 kV nnn

2.5 kV nnn

1.0 kV nnn

500 V nnn

250 V n n

10 V steps 50 V to 1 kV

25 V steps 1 kV to max. test voltage n n

10 V steps 100 V to 2.5 kV,

25 V steps 2.5 kV to max. test voltage n

Auto IR nnn

Auto PI nnn

Auto SV n n

Auto DD n n

Auto DAR nnn

Ramp test n n

CAT IV 600 V safety rating nnn

Timer control nnn

Alarm limit mode nnn

Compatible with PowerDB n n

User programmable lock voltage range nnn

Temp. recording (manual entry) n n

Real time clock n n

Battery charge time (hours) 2.5 2.5 2.5

Noise rejection 3mA 3mA 3mA

Guard terminal performance 2% error guarding 500 kΩ leakage with a 100 MΩ load

Model MIT1025 Panel

ISO STATEMENT

subject to change withot notice

ORDERING INFORMATION

These unique features improve insulation testing efficiency and effectiveness

CT17 9EN England

T +44 (0) 1 304 502101

F +44 (0) 1 304 207342

UNITED STATES

2621 Van Buren Avenue

Norristown, PA 19403 USA

T 1 866-254-0962 (USA only)

T +1 610-676-8500

F +1 610-676-8625

Oberursel GERMANY, Aargau

SWITZERLAND, Dubai UAE, Mumbai

INDIA, Johannesburg SOUTH AFRICA,

and Chonburi THAILAND