MicroOhmMeter  van IET Labs


The LOM-510A has 4 digits, a 0.02% basic accuracy and a 1 μOhm resolution. Its 4-terminal measurement technique eliminates lead resistance errors and 80 dB of ac noise rejection provides rock-steady readings even in noisy locations. The unit comes with rugged 4-terminal test clips and a large selection of optional probes, clips and fixtures allowing attachment to any low-resistance unknown.

Switched DC Mode:
Allows measurement of switch contacts, welds, shunts, PC board tracks and other primarily resistive elements. Thermal emf effects are eliminated.

Constant DC Mode:
Suitable for measuring the resistance of inductive components such as coils or transformers.

Pulsed Mode:
Provides low drive current to allow measurements of fuses, thermistors, and other thermally sensitive devices.

Dry Circuit:
Assures that oxides and film contacts are not punctured. The Dry Circuit Mode limits the open circuit voltage to 50 mV. The Model LOM-510A/20 limits the open circuit voltage to 20 mV.


Portability permits many field applications such as the measurement of very low resistances of rail or pipe bonds, welds, airframes, motors, transformers, and power distribution apparatus. The optional Model BP-511 Battery Driven ac Power Source will operate the microohmmeter from its internal battery for more than an hour continuously, worst case, and for an indeterminately large number of hours when used in normal operation.

The BP-511 AC Power Source can be mechanically attached to the micro-ohmmeter with the optional Model LOM-513 coupler kit, and both units come in heavy-duty metal cases. A built-in battery charger is provided as are LED's to indicate low-battery conditions and charger operation.