Microohmmeters / DLROs

Microohmmeters, also called digital low resistance ohmmeters, measure very low resistance by injecting a substantial test current and sensing voltage on separate leads.

Megger, Hioki, Extech, Hoyt Electrical and NDB Technologies cover this range. The four-wire Kelvin connection is what makes the measurement possible, since at these levels the resistance of the test leads themselves would otherwise dominate. Test current is the specification that decides the application: tens of amps suffice for bonding and joint checks, while circuit breaker contact resistance testing conventionally uses 100 A or more to reproduce service conditions and expose a marginal contact. Confirm the resolution you need.