Megger MOM200A 200 A Micro-Ohmmeter

The MOM200A is built for field‑use in industrial and utility environments. It delivers up to 200 A DC output current for precision measurement of contact resistances in critical components like high‑voltage circuit breakers, disconnect switches, and busbar joints. 
Despite its high output capability, the unit remains reasonably portable (≈14 kg) and includes flexible cable connections. Its measurement range extends up to about 20 mΩ (in some configurations) making it suitable for a wide variety of low‑resistance tests.
The instrument is mains‑powered (not battery) and uses 4‑wire (Kelvin) sensing to reduce lead effects, enabling accurate readings even under heavy current. The user manual shows that safety grounding, proper connection of current and sense leads, and controlled current ramp‑up are key to reliable measurements.

Features

• Up to 200 A DC test current, enabling measurement of low‑resistance connections under realistic load.

• Lightweight field‑friendly design (~14 kg) for portability in substation or service environments.

• Wide measurement capability: up to ~20 mΩ typical range.

• Uses four‑terminal Kelvin measurement technique separating current and potential circuits for accuracy.

• Suitable for measuring contact resistance in circuit breakers, busbar joints, isolators and other high‑current links.

• Designed for rugged industrial/utility use: flexible cable connections, field configuration, grounded safety.

• Mains‑powered (115/230 V depending on version) supporting robust continuous operation.

• Safety features and instructions provided in the user manual (e.g., thermal cut‑out, grounding, induction protection).

• Clear manual and accessory support for field connections, sense cables, current cables and transport case.

• Excellent choice when test current requirements stay at or below ~200 A, making it cost‑effective vs higher‑capacity units.

Includes

• Compact, rugged portable micro-ohmmeter
• Check low resistance levels of HV circuit breakers, disconnecting switches and busbar joints
• Output current from 0-200A DC
• Resistance ranges from 0 to 1999μΩ and 0 to 19.99mΩ
• Simple, easy-to-use interface
• Built inside its own carrying case