As a bonding meter or bonding milliohmmeter the AMPTEC 620UKB Bond Meter measure bonds similar to the AVTRON or  AVTRON T477W bond meter NSN 6625-01-119-7023 and model 101 bond micro ohmmeter, and the PPM or PPM instrumentation R1L-E2B measurement. The AMPTEC RESEARCH 620UK-B or amptec research low resistance can be a Ohmmeter including NSN 6625-01-542-7487  for use in explosive atmospheres and volatile environment fuel air areas and is intrinsically safe. Failsafe Ohmmeter, DLRO, bond tester, or AMPTEC 620A or  amptec dlro micro-ohmmeter. The amptech, or amptek EEX or Eex and  EEX Intrinsically safe Eex Intrinsically safe EBWalso ebw or eed tester can also be a ETL tester or EED or squib checker  continuity tester. 

AMPTEC 620UK-B Explosive Safety Bonding Milli-Ohmmeter A

NSN 6625-01-542-7587

*  4 ½ digit resolution from 0.0 milliohms to 1999.9 milliohms fullscale 

*  Selected by the USAF as the replacement for their aging inventory of old Bonding Meters - ideal replacement for obsolete, aging and over-priced 3 ½ digit AC Bonding Meters. As a ruggedized milliohmmeter The AMPTEC 620UK-B offers high accuracy (DC  - better than ½ milliohm), 4 ½ digit resolution, 0.1 milliohm resolution with "No Warm-up" required its ready to use when turned on.   

*  High Accuracy - 4 Wire Kelvin Milli-Ohmmeter with 0.5 milliohm basic accuracy from 0° to 40°C

*  Instant "ON", "No Waiting for a Warm-up Period", it's ready to use immediately after being powered up - The solid state internal reference(s) used by the AMPTEC 620UK-B Bonding Milli-Ohmmeter make it ready to use the instant it's water-proof power switch turned "on". 

* Intrinsically Safe and Certified to Mil STD 810, Method 511 (rev. F), use in an "Explosive and Volatile Atmosphere" compliant to +50°C (+122°F). It uses low voltage and low current ( <0.005 amperes) that will not cause ignition of flammable gases per MIL STD 810 Method 511.

*  All metal ( Faraday Cage) construction (front, back and all sides), textured powder coated aero aluminum      (AL 5052 alloy), all connected to front panel chassis ground jack.

* Separate battery compartment, operates on 4 ea "AA" Alkalines (i.e. Duracell ), field replaceable batteries (anyone can change the batteries) without breaking the calibration seal. There is "No access to any electronics inside the unit's battery compartment". It's also water-tight (gasket sealed compartment) and is corrosive resistant Per MIL PRF 28800D to any alkaline battery leakage or any chemical corrosion.

* Ruggedized use -Silicone rubber boot covers on all switches protects the instrument against saltwater spray, rain and dust.

* USAF's AMPTEC 620UK-B Bonding Ohmmeter NSN package (6625-01-542-7587) also includes 1) protective padding carrying case, 2) 4-Wire Kelvin Pistol Grip Probes (PG-401), 3) Operator/maintenance manual and 4) U.S.A. N.I.S.T Traceable Calibration Certificate  - MIL STD 130 Marking and MIL STD 129P packaging is optionally available. The AMPTEC 620UK-B Bonding Ohmmeter NSN package was selected by the USAF Aircraft Equipment Maintenance Team to modernize their inventory of old ohmmeters they been using since the 1970's. 

The AMPTEC 620UK-B Explosive Safety Bonding Ohmmeter (NSN 6625-01-542-7487) or bond meter is the USAF's portable digital milli-ohmmeter for "Intrinsically Safe" resistance bond testing in the presence of explosive and volatile hydrocarbon fuel air atmospheres ( i.e. aircraft electrical cable connection/bond and integrity of bolted connections). With volatile hydrocarbons ( liquid fuel air mixtures ) present around ordnance and aviation related electronics, the accidental discharge of a ignition source (spark) can be extremely hazardous. The AMPTEC 620UK-B Bonding Milli-Ohmmeter is certified USA MIL STD 810, Method 511, rev F  compliant for "Explosive Atmospheres" use to +50°C ( 122°F).  As a battery powered ( 4 ea, Alkaline "AA"), 4 ½ digit milliohmmeter ( bond meter ) , the portable AMPTEC 620UK-B can safely measure the resistance of cable lug to metal bonds, jumpers and bolted metal to metal connection integrity from 0.0 milliohms to 1999.9 milliohms.  The 4 Wire Kelvin test leads (handheld probe pistol grip set) automatically eliminate test lead length resistance errors and Kelvin probe contact resistance errors. The AMPTEC 620UK-B Safety Ohmmeter is based upon the AMPTEC 620UK Intrinsically Safe Ohmmeter design. It meets the EU ATEX Directive and the Intrinsic Safety standard Eex-ib-IIc-T4, is EMC tested in accordance with British DEF STD 59-41 Radiated Emissions & Susceptibility,  British DEF STD 66-31 (Heat, Cold, Humidity & related tests), and is US NAVY Ordnance Safety Board Approved for use on ESSM (Evolved Sea Sparrow Missile ) Rocket Motor and Warhead Squibs.

Rear Panel view of the AMPTEC 620UK-B Bonding Milliohmmeter

The AMPTEC 620UK-B bonding ohmmeter can typically operate for up to 1 year of normal use on a standard set of 4  "AA" batteries ( Duracell, Energizer etc). With the battery compartment separate from any internal electronics, the user can change the batteries and not effect the instrument's calibration. The battery compartment cover is gasket backed to provide a water tight seal. The battery compartment is also MIL PRF 28800D compliant to be protected against any battery corrosion ( leaking alkaline material).  There is also a convient side panel mounted easy grip handle for carrying the unit outside of its padded case ( NSN package etc.).

Easy to Calibrate "No Covers to Remove"

In addition, once the tamper resistant calibration sticker is removed the the AMPTEC 620UK-B Bonding Milli-Ohmmeter's rear panel, it's a breeeze to calibrate. There are "No Covers" to remove, the PMEL or calibration facility simply connects the 620UKB to the proper Primary Resistance Standard and has two simply adjustments to make ( zero set@10 milliohms and fullscale set@1.000 ohm). Calibration hole plugs are also included (inside carrying case pocket) if the AMPTEC 620UK-B Bonding Milliohmmeter user desires to use them.

MIL STD 810, Method 511, rev F "Explosive and Volatile Atmosphere" Laboratory Tested to +50°C

The AMPTEC 620UK-B Bonding Milliohmmeter circuitry is directly derived fron the multi-ranging AMPTEC 620UK Explosive Safety Ohmmeter, which has been independently laboratory certified as MIL STD 810, Method 511 (revision F) Explosive and Volatile Atmosphere compliant up to +50°C. The AMPTEC 620UK Explosive Safety Ohmmeter was remotely operated in an explosive atmospheric chamber ( Optimal Air fuel mixture with highly volatile hexane which has a volatility index equivalent to a 130 Octane rating@ +50°C). 

At an Independent Certified Test Laboratory in Los Angeles, CA - While fully operational, the AMPTEC Explosive Safety Bond Meter's test leads were successfully shorted then "opened" 400 times in the "saturated" explosive atmospheric fuel air mixture (Per MIL STD 810 Method 511 Rev F.). It was shown to be fully MIL STD 810 Method 511 Rev F. "Explosive and Volatile Atmospheres" compliant @ +50°C. A copy of the test report is available ( 620UK MIL STD 810_Method 511 test ) .

U.S. NAVY Ordnance Safety Board ( Indianhead MD) Approved -  For use on Evolved Sea Sparrow Missile Warhead and Rocket Motor Squibs (ESSM )

The AMPTEC 620UK Explosive Safety Ohmmeter has also been US NAVY Ordnance Safety Board Approved for use on Evolved Sea Sparrow ( ESSM) Missile squibs - including rocket motor and warhead missile squibs. A copy of the US NAVY Ordnance Safety Board Approval is available for your review. ( AMPTEC 620UK - ESSM APPROVAL ) The AMPTEC 620UKB Bond Meter uses the same 620UK Failsafe Current Source Circuit, same Digital Voltmeter Electronics, same metal case and chassis as the AMPTEC 620UK Explosive Safety Intrisically Safe ( EEx) Ohmmeter.

The AMPTEC 620UK-B Bond meter's ITT "Trident" weather-proof connector with cap provides a secure & popular military spec 4 Wire Kelvin resistance "Test Lead" connection and a chassis ground pin. The benefit of it being a 4-Wire Kelvin milliohmmeter is test lead length offset errors and test lead contact reistance errors are automatically eliminated. In addition any of AMPTEC's 630 series 4-Wire Kelvin test leads, jacks and handheld mini and micro-probes are compatible with the AMPTEC 620UK-B bond meter front panel Tridenttm connector.  

The NSN package includes 4 Wire Kelvin Pistol Grip Probes

The AMPTEC 620UKB Bonding Ohmmeter NSN package (NSN 6625-01-542-7487) includes a set of 4 Wire Kelvin Pistol Grip Probes ( Option PG-401). Each pistol grip probe has two spring loaded heavy duty rounded end tips. Sharped pointed tip based probes are also available upon request. All AMPTEC 630 series 4-Wire Kelvin test leads (i.e. banana jacks, handheld micro-probes etc.) are compatible with the AMPTEC 620UKBtm 4-Wire Kelvin test lead connector. Bonding Milli-Ohmmeter as they ( 630ES, 630BN etc.) are all designed to connect to the same front panel ITT Canon Trident (see photo below)

Option 630-304 Gold Plated Kelvin Mini-probes are available along with a host of test leads and accessories.

No Hazardous Mercury Batteries - Any brand of Alkaline "AA" battery will work

The AMPTEC 620UKB Bonding Ohmmeter does not use hazardous mercury batteries like those used in the older model ohmmeters.  It can be powered by any standard high quality brand "AA" Alkaline batteries ( Duracell Ultra or Duracell Coppertoptm MN1500, Energizer, Eveready etc. requires 4 each). The AMPTEC 620UK-B Bonding Milliohmmeter can be safely used with any brand of alkaline "AA" battery, cheaper quality brands of batteries will simply not last as long. 

Acrylic Epoxy Encapsulated Coated Circuit Board and More ...

A common question we get from evaluating safety engineers is "What sort of corrosion preventative on components on the PCB and electrical and  mechanical  measures are taken with the AMPTEC 620UKB to prevent an internal  loose wire, metal screw, or washer inside from floating around and shorting the battery output to the terminal output connections?".  The ohmmeter's output connections are insulated inside the unit with heat shrink tubing covering any of it's conductive surfaces.  The entire PCB (except for the calibration trim pots) is also non-conductive acrylic epoxy encapsulated/coating, to make it extremely difficult to get an accidental conductive pathway. This coating also provides excellent humidity protection and resistance to environmental extremes ( dust etc.)