AOIP OM21 Programmable Benchtop Micro-Ohmmeter – High Accuracy: 0.03 %


The OM 21 programmable table micro-ohmmeter is intended for 4-wire measurement of very low resistance resistances up to 20 kΩ with an excellent maximum accuracy of 0.03% and a resolution of only 0.1 µΩ. The reliability and the precision of the measurements is reinforced by the low temperature coefficient (10 ppm / ° C), the automatic compensation of the electromagnetic forces before each measurement carried out, the temperature compensation of the nature of the metal and the room temperature compensation.


AOIP OM21 is a programmable table micro-ohmmeter designed for 4-wire measurements of very low resistance up to 20 kΩ. It boasts an impressive maximum accuracy of 0.03% and a resolution of just 0.1 µΩ. The reliability and the precision of the measurements is reinforced by the low temperature coefficient (10 ppm / ° C), Its reliability and precision are ensured by features like low temperature coefficient (10 ppm / ° C).

AOIP OM21 offers three measurement current options – continuous, pulsed, or alternating – ranging from 100 µA to 10 A. It’s versatile in start-up and sampling conditions, making it suitable for various sectors and applications. It can measure resistance and resistivity of cables, inductive resistances like motor coils and transformers, contact resistance of connectors and switches, test low-power electrical components such as fuses, and assess devices responsive to temperature. It’s also useful for metallization control, earthing, and checking earth continuity.

AOIP OM21 is user-programmable, either directly on the device or through LOG OM software. It allows customization of measurement settings, alarms, and storage options. It can save up to 1000 measurements in its memory for later review on the device or a PC. No internal adjustment is needed for electronic calibration. For repetitive measurements, AOIP OM22 is recommended for test bench use, offering similar features but with 6 preset configurations for convenience.


Dimensions L x W x H 225 x 88 x 310 mm
Mass 2 to 3 kg depending on options
Screen 26,000-dot LCD, 16 illuminated segments 11.5 mm high
Food 115/230 V (50/60 Hz)
Battery with integrated charger (optional) Type: 12 V battery
Autonomy: 2 to 8 h depending on use
Charging time: 14 h
Communication interfaces • RS 232 as standard
• IEEE 488-2 optional
Allow the complete programming of the instrument, the exploitation of the measurements, the electronic calibration of the instrument
Memory 1000 measurements with average, minimum or maximum value
Memory read-back on the screen or operation by digital and analog interfaces
Reference area 23 ° C ± 1 ° C (45 to 75% RH non-condensing)
Nominal operating range 0 to 50 ° C (20 to 80% RH non-condensing)
Operating limit range -10 ° C to + 50 ° C (10 to 80% RH non-condensing)
Storage conditions – 30 ° C to + 55 ° C
(- 15 ° C to + 50 ° C with charged battery)
Protection sign IP40 according to EN60529
Maximum altitude 2500 m
Protections •  Electronics on ‘voltage’ wires
•  By fuse on the ‘current’ wires
•  Against the opening of the ‘current’ circuit in measurement of inductive resistances
Classroom Complies with European standard EN 61010-1
Category III, pollution 2
Assignment voltage with respect to earth 50 V
Shock and vibration resistance EN61010-1
EMC compliance Immunity:
• EN 50082-1 / 1992Radiated emission and conduct:
• EN 55022, class B
• Radiated fields: IEC 801-3 / 1984
• Conducted disturbances: IEC 801-4 / 1988.
• Electrostatic discharges: IEC 801-2 / 1991


AOIP OM 21 Programmable benchtop micro-ohmmeter – High accuracy 0.03 _-DpstarGroup