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AMPTEC 620LK-HR Intrinsically Safe Bonding Ohmmeter

The AMPTEC 620LK-HR is high resolution version of the 620LK Intrinsically Safe Bonding Tester. AMPTEC’s 620LK-HR is an affordable highly accurate In-circuit Connection-Resistance bond tester. Additionally, the 620LK-HR has four (4) low ohmic ranges to confirm bonding resistance. The 20mΩ range provides .001 mΩ resolution while the 2Ω range provides 0.1mΩ. Originally designed for Lockheed Martin, the 620LK product line comes from a long lineage of intrinsically safe bonding testing equipment that now occupies a more commercialized space.

The AMPTEC 620LK-HR Bonding Ohmmeter is an Intrinsically Safe Bonding Resistance Tester. This meter is capable of performing bonding measurements on a variety of components including metal-to-metal connections. The 620LK-HR has been independently UL-913 certified, ensuring quality and safety at each step of manufacturing. Due to its Safety Certifications and high level of accuracy, the AMPTEC 620LK-HR meter is the choice bond testing meter for countless Aircraft Maintenance Shops as well as many Commercial Airliners, while its sibling the 620UK-B is in numerous USAF programs.

AMPTEC 620LK-HR Intrinsically Safe Bonding Tester Ohmmeter

The AMPTEC 620LK-HR Bonding Milli-Ohmmeter is UL-913 approved as an Intrinsically Safe apparatus for use in Class 1, Division 1, Groups A, B, C, and D locations for ambient temperatures from -20° C to 50° C (T3 zones). The AMPTEC 620LK-HR meter is also MIL. STD. 810 MTD. 511 approved for use in explosive and volatile fuel-laden atmospheres.

The 620LK-HR purchase includes:

  • 620LK-HR Intrinsically Safe Bonding Tester Ohmmeter
  •  Kelvin Cable Lead Set (630-406s) 
  • OP-300 Padded Case
  • NIST traceable Calibration Certificate
  • Certificate of Conformity
  • Manual downloadable
  • Warranty letter

AMPTEC 620LK Aircraft Bonding Ohmmeter

AMPTEC 620LK-HR High Resolution Intrinsically Safe Bonding Ohmmeter Tester 





Nominal Current











± .025% of range

Full Scale

19999 LEDs


The 620LK-HR Bonding Ohmmeters are available for purchase in two separate packages and are compatible
with the 630/640/641 Series accessory line.

For specific pricing information or to place an order for a 620LK-HR meter, please contact ATEquip today.





620LK-HR Bonding Ohmmeter, 630-100 Padded Case, 630-406S Probes, HR-DC Battery Charger, N.I.S.T. Calibration Certificate

ATEquip is a SAM.GOV Cage Code 5PF05 registered company with the New Entity ID: H5H4KAHBASC7

AMPTEC RESEARCH is an ISO 9001:2015 Certified Accredited Quality Management System Company