Megger Micro Ohmmeter with Kelvin Clamps

Specifications (PDF)

Description

TheMegger MOM2 microhmmeter is a handheld contact resistance test instrument thatweighs only 2 lbs. Thanks to a new ground breaking technology, this instrumentcan reliably produce a test current up to 220A. It also complies with IEC62271-100, IEEE/ANSI C37.09-1999 and C37.100-1992 standards. It is batteryoperated and performs 2200 tests per charge.

Designed for any customer that needs more than 50A or 100A to perform alow resistance measurement and store up to 190 records.

• Up to 220 A

• Battery operated

• Handheld, lightweight – 2.2 lb (1 kg)

• Safe test – DualGround™

• Auto range: 1 µÙ to 1000 mÙ

• Bluetooth® PC communication

• Ultra capacitor technology (patent pending)

Applications

The MOM2 test system is designed toserve a number of applications. The mostcommon are contact resistance measurements oflow-, medium- and high-voltage breakers andalso at bus-bar joints, and other high current links.If the contact resistanceis too high, this will lead to power loss andtemperature rise, which often leads to serious trouble.To avoid such problems, it is necessary to check theresistance at regular intervals.The following table demonstrates how importantlowresistance is at high currents:

Current Contact resistance Powerloss

• 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 theresistance 0.1 mÙ gives a power loss of 10kW. This power loss in one single point willdefinitely confer a temperature rise, which may result inoverheating and possibly premature failure.

Thisinstrument was designed to serve a number of applications. Some of which areshown below:

• Circuit Breakertesting

– Circuit breaker contacts

– Connections to the breaker

• Testingof Bus-bar

– Bus-barjoints

– Connections

• Everywhere you need to test a lowresistance / high currentconnection

– Switches

– Disconnectingdevices

– Safetyground connections

– Weldingpoints

– Fuses

– Cables

• Testing switches, connectors and relays – Toensure contact resistance is within specified values.

• Cableresistance – too low means too much copperin cable (higher costs), too high means not enoughcopper (cables’ current carrying capacity compromised)

• Motors– To determine heat rise under load, measurewinding resistance, check for short circuits or opencircuits.

• Generators– To determine heat rise under load, measurewinding resistance, check for short circuits oropen circuits.

• Fuses– To ensure resistance is within specified values.

• Cablelooms – Checking bonding and interconnectionswhen installing in equipment, racks etc.

• UPS / Car batteries – Carrier toplate weld resistance, highresistance indicates poor weld quality that will restrict battery’s ability tocarry current.

• Aircraftassembly and maintenance

• Mainframe electrical and mechanical bonds to ensure a stable “ground plan”to protect aircraft from static electricity and lightning strikes.

• Staticwick bonding

• Antennabonds

• Controllinkage bonding

• Battery connection andinterconnection

• Integrityof structure and exhaust system

• Metalliccoating resistance

• Railway/ Railroad Industry

• Strapand wire bonds between rail segments – maintaining performance of controland telephone system. Minimizing power loss on three rail systems.However sometime higher test currents are specified.

• Cablejoints – power system efficiency.

• Earth/ ground bonds – e.g. lightning protection onstructures. Ground mats, ground conductor rings,metal cladding, metal ceilings, metal floors, hand rails, seats etc. tolimit step and touch potential.

• Platformedge doors – Earth / ground bonding (mainlyunderground systems)

• Aluminum refineries

• Graphite electrodes – to verifydensity

• Shipbuilding or any metal structures

• Weldquality – measure at regular intervals along weld length looking foruniformity.

• Installedequipment bonds – to steel structure /hull.

• Rawmaterial processing, e.g. cement plants

• Powercarrying elements – installation and maintenance

• Ground bonds – cement is corrosive

• Automotive industry

• Cable leads in robot spot welderswork-harden through flexing causingstrands to break. Results in poor weld quality.

• Power Generation and Distribution

• Bus bars – lap joint tests tomaintain low resistance, and hencemaintaining efficiency and reducing likely hoodof fire.

• Cablejoints – including overhead lines. High impedance joint can explode.

• Fuses– connections

• UninterruptiblePower Supply (UPS)

• Batterystraps – quality of connections. Preventingpotential of fire and failure to operate

• Carrier to plate weld resistance –High resistance indicates poor weldquality that will restrict battery’s ability to carry current.

• Militaryvehicles – Trucks, tanks etc.

• Installedequipment such as radio equipment – ground bonding to vehicle chassis.

• Buildings– wiring, lightning protection bonds

• Variousbond, both for power distribution and earthgrounding – check for step and touch voltagesafety in fault condition.

• Conduitcontinuity – metal conduit, detect corrodedor loose threads etc.

• Pipelines

• Cathodicprotection – check connection etc. Toughenviron