The UNI-T UT620C+ Micro Ohmmeter is a professional portable low-resistance tester designed for accurate measurement of electrical connections, windings, conductors and components where very small resistance changes matter.

Using the 4-wire Kelvin measurement method, the UT620C+ helps minimise the effect of test lead resistance and provides reliable measurements down to the micro-ohm level. With a measurement range from 0.001mΩ to 300kΩ, up to 1A test current and accuracy up to ±0.1% FS, it is ideal for electrical maintenance, manufacturing, automotive, power distribution and industrial testing.

Its compact handheld design, rechargeable lithium battery and storage for up to 500 measurement records make it suitable for both field and workshop use.

Ideal For

The UT620C+ is particularly useful for engineers and technicians carrying out:

• Busbar and electrical joint testing – identify loose, deteriorated or high-resistance connections before they cause overheating or failures.
• Motor and generator testing – measure winding resistance and compare phases during commissioning and maintenance.
• Transformer maintenance – check winding and connection resistance.
• Switchgear and circuit breaker testing – evaluate contact resistance across switches, breakers, relays and contactors.
• EV and battery manufacturing – test welded joints, conductors, terminals and motor/stator windings.
• Cable and conductor testing – measure resistance of wires, cables, connectors and terminations.
• Fuse and component testing – accurately evaluate low-resistance electrical components.
• Industrial preventative maintenance – identify increasing contact resistance before it develops into an operational problem.

• Specification	UT620C+
  Resistance Measurement Range	0.001mΩ – 300.0kΩ
  Maximum Resolution	1µΩ
  Accuracy	Up to ±0.1% FS
  Measurement Method	4-wire
  Maximum Test Current	≤1A
  Open Circuit Voltage	≤4.2V
  Input Protection	≤36V AC/DC
  Measurement Speed	Approx. 2 readings/sec
  Data Storage	500 sets
  Display	Segment LCD with backlight
  Interface	USB Type-C
  Auto Power Off	Approx. 15 minutes
  Ingress Protection	IP54
  Battery	3.7V 3200mAh rechargeable lithium
  Measurement Power	≤8W
  Dimensions	161 × 117 × 68mm
  Weight	Approx. 480g including battery
  Certifications	CE, RoHS
  Measurement Ranges
  Resistance Range	Test Current	Resolution
  0.001mΩ – 100.00mΩ	1A	0.001 / 0.01mΩ
  100.1mΩ – 1000.0mΩ	100mA	0.1mΩ
  1.001Ω – 10.000Ω	10mA	0.001Ω
  10.01Ω – 100.00Ω	1mA	0.01Ω
  100.1Ω – 1000.0Ω	100µA	0.1Ω
  1.001kΩ – 10.000kΩ	10µA	1Ω
  10.01kΩ – 100.00kΩ	3µA	10Ω
  100.1kΩ – 300.0kΩ	3µA	100Ω