Megger MJ15 Specifications

Analogue 5 kV Insulation Tester

BM15 MJ15

Analogue 5 kV Insulation Tester

■ Four test voltages to 5 kV

■ Dual power supply option giving the best

of both worlds

■ Resilient mounted analogue scale for

robustness

■ Voltage range to 600 V indicates auto

discharge

■ Pass/fail overlays for rapid testing

■ Single scale for insulation values to avoid

operator error

BM15 MJ15

DESCRIPTION

The Megger®BM15 & MJ15 are compact 5 kV insulation
testers. They are very simple to use and provide a quick
and accurate reading of insulation resistance. The
instruments use an analogue display with a maximum
reading of 20 GΩ. The BM15 is powered by batteries. The
MJ15 has an additional hand-cranked generator.

The instrument operation is extremely simple. A voltage
range enables measurement of a.c. or d.c. conductor
potential. Four test voltages are available at 500 V, 1 kV,
2,5 kV and 5 kV. A choice of push buttons is supplied; a
locking button simplifies long term testing, or a non­locking version is preferred for maximum safety.

A bezel allows a scale plate overlay to be added with
pass/fail bands for go/no go testing. This is particularly
useful for less experienced users and enables a rapid
decision to be made.

The new instruments have a choice of power source. The
BM15 is powered by 8 x LR6 (AA) alkaline cells. The MJ15
comes with a hand cranked generator plus batteries. If the
test button is pressed the MJ15 uses battery power.
Otherwise the crank handle is turned to save battery
power or for use when the batteries are unavailable.

Both units are built into a rugged case designed for
outdoor use. The instruments are also supplied with a soft
carrying case, a test lead set, test record cards and
batteries.

Safety terminals suitable for locking connectors are used
for connection to the test piece. An automatic discharge
circuit eliminates the voltage on capacitive loads after a
test. The decaying voltage can also be viewed on the
scale.

Fused test leads are available as an option for voltage
measurement. The instruments meet the IEC1010 safety
specification and EMC specifications and are fully CE
marked.

FEATURES

■ Large, single scale analog display

■ Auto voltage measurement function indicates conductor

and auto discharge potential

■ Supplied with optional locking test button

■ Safety recessed terminals and long connectors

■ Four output test voltages

■ Simple to use

■ CE marked

■ Dual power supply option on MJ15

■ Unique scale overlay for pass/fail bands

■ Resilient mounted analogue scale for robustness

■ Single scale for insulation values to avoid operator error

■ Light weight and rugged

■ Range down to 100kΩ ideal for go/no go testing

BM15 MJ15

Analogue 5 kV Insulation Tester

APPLICATIONS

Insulation is important for the safety of all electrical
systems, providing a barrier to hazardous live conductors.
Insulation can deteriorate due to the affects of moisture,
sunlight and heat. A reduction in the value of insulation
resistance can lead to a potentially dangerous situation
caused by the dangers of electric shock, or arcing causing
fire. If insulation resistance is regularly monitored
unusually low values can be investigated before they
cause danger, or inconvenience and cost due to
equipment downtime for repairs.

The BM15 & MJ15 are general purpose, 5 kV insulation
testers for electrical contractors and engineers who test
machinery, transformers, switchgear, cables, etc.

This Product is used by:

■ Electrical Contractors

■ Maintenance Engineers

■ Telecommunications Engineers

■ Gas and Water Utilities

■ Railway Companies

■ Cable Manufacturers

■ Mining Companies

SPECIFICATION

Insulation Range:

100 kΩ to 20 GΩ (also 0 Ω and ∞)

Test Voltages (d.c.)

500 V, 1000 V, 2500 V & 5000 V

Test Voltage Accuracy

±5% of nominal test voltages on 20 MΩ load

Test Voltage Stability

<±1% (180 r.p.m. to 240 r.p.m. MJ15)

Insulation Accuracy (at 0 - 30˚C) (32 to 86˚F)

±2,5% of full scale deflection

Short Circuit Current

1,5 mA ± 0,5 mA

Maximum capacitance of load

5 µF

Interference Rejection

1 mA rms at 50 to 60 Hz

Discharge Resistor

<500 kΩ

Voltage RANGE

Range

0 to 600 V a.c.

Indication of d.c.

Accuracy

± 2,5% f.s.d. a.c.

(with rotary switch in the V position)

General

Overload rating

720 V a.c. or d.c.

Scale Length

2,8 in. (72 mm) (96˚)

Power Supply

BM15

8 x AA cells (LR6)

MJ15

Low voltage brushless Generator and 8 x AA cells (LR6)

Battery Life

Typically 2000 five second tests at 5 kV on 100 MΩ load

Battery Indicator

Loaded battery test

Safety

Meets the safety requirements for double insulation to IEC 1010-1
(1995) EN61010 (1995) to installation Category III***, 300 V phase
to earth (ground) or 600 V Category I*

***Relates to transient overvoltage likely to be found in fixed
installation wiring.

*Relates to transient overvoltage likely to be found in special
equipment or parts of equipment, telecommunication, electronic
etc.

Non Replaceable Fuse

1 Amp, 250 V, HBC type (F)

(20 mm x 5 mm) to IEC 127/1
This fuse protects the instrument against any faults occurring
when using rechargeable batteries.

EMC

In accordance with IEC61326 including Amendment No. 1.

Temperature RangeOperating

32ºF to 86ºF (0ºC to 30ºC) at full specification

-4ºF to 122˚F (-20ºC to 50ºC) with temperature coefficient
±0,1%/ºC (0,05% /ºF)

Storage

-13ºF to 149ºF (-25ºC to 65ºC)

Humidity Range

90% RH at 104ºF (40ºC)

Dimensions

8,9 in. x 6,3 in. x 4,5 in.

(220 mm x 160 mm x 115 mm)

Weight

BM15 Approx 2,6 lbs (1,2 kg)

MJ15 Approx 3,5 lbs (1,6 kg), or 4 lbs (1,8 kg) with battery

holder and cells.

BM15 MJ15

Analogue 5 kV Insulation Tester

Typical Terminal Voltage Characteristics

UK

Archcliffe Road Dover
CT17 9EN England
T [phone]
F [phone]

UNITED STATES

4271 Bronze Way
Dallas TX 75237-1088 USA
T 800 723 2861 (USA only)
T [phone]
F [phone]

ORDERING INFORMATION

Item (Qty) Order No.

Battery powered 5 kV insulation tester BM15
Hand crank/battery 5 kV insulation tester MJ15

Included Accessories

User Guide 6172-209
3 x 3m HV leads 8101-181
Carrying case with lead storage 6420-117
Slide in Pass Band overlay (5 supplied) 6121-401
Test Record Card (pack of 5) (U.S. 210949)
8 x AA cells (LR6)

Optional Accessories

Fused test probes, 1,5 m long (2 used) 6320-240
Test Record Card (Pack of 20) 6111-216
CB101; 5 kV Calibration Box 6311-077

Publications

‘A Stitch In Time’ AVTM21-P8B
’Lowdown on HV d.c. Testing’ AVTM22P-1

OTHER TECHNICAL SALES OFFICES

Norristown USA, Toronto CANADA,
Mumbai INDIA, Trappes FRANCE,
Sydney AUSTRALIA, Madrid SPAIN
and the Kingdom of BAHRAIN.

Registered to ISO 9001:2000 Reg no. Q 09290

Registered to ISO 14001 Reg no. EMS 61597

BM15_MJ15_DS_en_V12

www.megger.com
Megger is a registered trademark