Megger MOM2 microhmmeter is a handheld contact resistance test instrument that
weighs only 2 lbs. Thanks to a new ground breaking technology, this instrument
can reliably produce a test current up to 220A. It also complies with IEC
62271-100, IEEE/ANSI C37.09-1999 and C37.100-1992 standards. It is battery
operated and performs 2200 tests per charge.
Designed for any customer that needs more than 50A or 100A to perform a
low resistance measurement and store up to 190 records.
Up to 220 A
Handheld, lightweight – 2.2 lb
Safe test – DualGround™
Auto range: 1 µÙ to 1000 mÙ
Bluetooth® PC communication
Ultra capacitor technology
The MOM2 test system is designed to
serve a number of applications. The most
common are contact resistance measurements of
low-, medium- and high-voltage breakers and
also at bus-bar joints, and other high current links.If the contact resistance
is too high, this will lead to power loss and
temperature rise, which often leads to serious trouble.
To avoid such problems, it is necessary to check the
resistance at regular intervals.The following table demonstrates how important
lowresistance is at high currents:
Current Contact resistance Power
10 kA 1 mÙ 100 kW
10 kA 0.1 mÙ 10 kW
1 kA 1 mÙ 1 kW
1 kA 0.1 mÙ 100 W
At 10 kA a contact with the
resistance 0.1 mÙ gives a power loss of 10
kW. This power loss in one single point will
definitely confer a temperature rise, which may result in
overheating and possibly premature failure.
instrument was designed to serve a number of applications. Some of which are
Circuit breaker contacts
Connections to the breaker
Everywhere you need to test a low
resistance / high current
Testing switches, connectors and relays – To
ensure contact resistance is within specified values.
resistance – too low means too much copper
in cable (higher costs), too high means not enough
copper (cables’ current carrying capacity compromised)
– To determine heat rise under load, measure
winding resistance, check for short circuits or open
- To determine heat rise under load, measure
winding resistance, check for short circuits or
- To ensure resistance is within specified values.
looms – Checking bonding and interconnections
when installing in equipment, racks etc.
UPS / Car batteries - Carrier to
plate weld resistance, high
resistance indicates poor weld quality that will restrict battery’s ability to
assembly and maintenance
frame electrical and mechanical bonds to ensure a stable “ground plan”
to protect aircraft from static electricity and lightning strikes.
Battery connection and
of structure and exhaust system
/ Railroad Industry
and wire bonds between rail segments – maintaining performance of control
and telephone system. Minimizing power loss on three rail systems.
However sometime higher test currents are specified.
joints – power system efficiency.
/ ground bonds – e.g. lightning protection on
structures. Ground mats, ground conductor rings,
metal cladding, metal ceilings, metal floors, hand rails, seats etc. to
limit step and touch potential.
edge doors – Earth / ground bonding (mainly
Graphite electrodes – to verify
building or any metal structures
quality – measure at regular intervals along weld length looking for
equipment bonds – to steel structure /
material processing, e.g. cement plants
carrying elements – installation and maintenance
Ground bonds - cement is corrosive
Cable leads in robot spot welders
work-harden through flexing causing
strands to break. Results in poor weld quality.
Power Generation and Distribution
Bus bars – lap joint tests to
maintain low resistance, and hence
maintaining efficiency and reducing likely hood
joints – including overhead lines. High impedance joint can explode.
Power Supply (UPS)
straps – quality of connections. Preventing
potential of fire and failure to operate
Carrier to plate weld resistance –
High resistance indicates poor weld
quality that will restrict battery’s ability to carry current.
vehicles – Trucks, tanks etc.
equipment such as radio equipment - ground bonding to vehicle chassis.
– wiring, lightning protection bonds
bond, both for power distribution and earth
grounding – check for step and touch voltage
safety in fault condition.
continuity – metal conduit, detect corroded
or loose threads etc.
protection – check connection etc. Tough
environment ideal for the DLRO10HD
turbines Lightning protection –
wing tip to base, or component parts
in manufacture. Long test leads available
for this application.
ground bonds – various