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 intrinsilly 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. 

Presently (as of 02NOV, 2011) we have standard version AMPTEC 620LK Low Resistance Bonding Milli-Ohmmeter(s) in STOCK and "On-The Shelf". Your AMPTEC 620LK Bonding  Milli-Ohmmeter either the  "Airline Package" and/or "LM" packages (see below for accesory/package description) can ship same day as ordered (credit card orders, established customer etc.)

AMPTEC 620LK (Ultra Low Resistance) Explosive Safety Bonding Milli-Ohmmeter 

Derived from the USAF's AMPTEC 620UK-B Bonding Milliohmmeter, the brand new AMPTEC 620LK Low Resistance Safety Bonding Milliohmmeter measures even lower bond resistance levels with even better

resolution and better accuracy. Designed originally for measuring very low resistance bonds that are less than ½ milliohm (on the Lockheed Martin F-35 Joint Strike Fighter). The standard version AMPTEC 620LK Bonding Milli-ohmmeter's failsafe constant current source operates with a 100 mA and is accurate to 0.1 milliohms (0.01 milliohm resolution).

Bond Measurements made Easy -
Focus on the Probe Placement not the Meter 
The "Auto-Lock" feature automatically "Locks-On" & holds (displays) the lowest ohm bond measurement for 10 seconds then automatically resets. The intelligent AMPTEC 620LK's "Auto-locks", once continuity is established, onto the lowest resistance (bond) measurement automatically. This allows the operator to focus on proper Kelvin probe placement on the test device (i.e. aircraft) without having to look at the meter while measuring, no range changes to deal with, no zeroing of the test leads. No erroneous readings, only when continuity is made, does it continuously sample measurements and lock in the lowest resistance reading and holds/displays it for 10 seconds (display backlight also comes on), then automatically resets (or manually select the front panel "Auto Measure Reset" switch to start over).



Lightweight - It only weighs 3 1/2  Lbs,  so little weight that it can be carried around your neck (Side panel "D" ring clipped onto the carrying case strap) and can make measurements while still in the case, (Hands Free) without having to hold the meter. An Optional Transit Case "OP-100" a hardshell impact resistant foam lined transit case is also available. 

*  4 ½ digit resolution, automatic ranging  from 000.01 milliohms to 2.0 Ohms fullscale 

*  Enhanced Designed based upon the USAF Bonding Meter (USAF's original AMPTEC 620UKB Bond Meter) - ideal replacement for obsolete, aging and over-priced 3 ½ digit AC Bonding Meters. As a ruggedized milliohmmeter The AMPTEC 620LK offers high accuracy (DC  - better than 0.1 milliohm), 4 ½ digit resolution, 0.01 milliohm resolution with "No Warm-up" required its ready to use when turned on.   

*  High Accuracy - 4 Wire Kelvin Milli-Ohmmeter with 0.1 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 620LK Bonding Milli-Ohmmeter make it ready to use the instant it's water-proof power switch turned "on". 

*  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 (Duracell Coppertops) or Optional Rechargeable "AA" (NiMH cells ), 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.

* AMPTEC 620LK Bonding Milli-Ohmmeter Commercial Air Package available:

1) Includes the protective padded carrying case (holds the bond meter and the probes, see photo above).

2) 4-Wire Kelvin Handheld Probes (OP630-406S Mini-probes - 5' long covers a 10' spread) part of the Commercial Air Package (similar to 10' OP630-405S long photo below) along with the US NIST Traceable Calibration Certificate and Operator manual.

Option 630-405S Heavy Duty Spring Loaded Gold Plated Kelvin Probes (10' long)

The "LM" Package of Heavy Duty Spring Loaded Gold Plated Kelvin Probes include a 10' long set (20 ' span - see photo shown above) of spear tipped Probes plus a 5' long Heavy Duty Spring loaded Kelvin Probes and a spare set of spiked tips (can be swapped out using a pair of pliers). The LM package for the AMPTEC 620LK Bonding Milli-Ohmmeter also includes the padded carrying case, U.S. N.I.S.T. Traceable Calibration Certificate and operator manual (1 year warranty). These OP630-405S Heavy Duty Spring Loaded Gold Plated Kelvin Probe tips are about 50% stronger spring compression than the standard 4' long AMPTEC Kelvin Mini-probes that are part of the more economical "Commercial" package. The sharp point tips themselves are also stronger and a 30% larger diameter than the standard AMPTEC commercial Kelvin Min-probe tip.

3) Operator/maintenance manual and 4) U.S.A. N.I.S.T Traceable Calibration Certificate. The AMPTEC 620LK Low Ohm Bond Meter is the ideal replacement for Aircraft Equipment Maintenance Team's to modernize their inventory of old heavy bonding ohmmeters they been using since the 1970's. 

As a battery powered ( 4 ea, "AA" alkaline), 4 ½ digit milliohmmeter (bond meter) , the lightweight portable. AMPTEC 620LK Bond Milli-Ohmmeter can safely measure the resistance of cable lug to metal bonds, jumpers and bolted metal to metal connection integrity from 0.01 milliohms to 1999.9 milliohms.  The 4 Wire Kelvin test leads (handheld probe set) automatically eliminate test lead length resistance errors and Kelvin probe contact resistance errors. The AMPTEC 620LK Safety Bond Milli-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 620LK Bonding Milliohmmeter

The AMPTEC 620LK Bonding ohmmeter normally comes with 4 ea. disposible AA Alkaline batteries (ie Duracell coppertop), and battery life with disposible batteries depends on the usage (typically several weeks of use). The Optional "NiMH" can typically operate for years of normal use on a standard set of 4  "AA" rechargable batteries (Rechargeable NiMH - 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).  

Easy to Calibrate "No Covers to Remove"

In addition, once the tamper resistant calibration sticker is removed from the AMPTEC 620LK Bonding Milli-Ohmmeter's rear panel, its easy to get to the unit's two calibration access holes and it's a breeeze to calibrate. There are "No Covers" to remove, the PMEL or calibration facility simply connects the 620LK to the proper Primary Resistance Standard and has two simple adjustments to make (Fullscale@100 milliohms and 10% of scale@1.00 milliohm). Calibration hole plugs are also included (inside carrying case pocket) if the AMPTEC 620LK Bonding Milliohmmeter user desires to use them.

Independent Certification - Environmental Test Laboratory in Los Angeles, CA - While fully operational, the AMPTEC 620LK 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. "Explosive Atmospheres").

It was shown to be fully MIL STD 810 Method 511 Rev F. "Explosive and Volatile Atmospheres" compliant @ +50°C.  This means the AMPTEC 620LK Safety Bond Milliohmmeter when making contact with the item under test ( aircrfat chassis, fuel tank etc) does not produce sparks with minimal kinetic energy levels (not hazardous, will not ignite jet fuel or other volatile hydrocarbons).

IP54 - Ingress Protection Rated (Water Spash)

The AMPTEC 620LK Bond meter's ITT "Trident" weather-proof connector  (IP-54) 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 620LK bond meter front panel Tridenttm connector.  

Optional 4 Wire Kelvin Pistol Grip Probes

The AMPTEC 620LK Bonding Ohmmeter Commercial package includes: Padded Carrying Case, Manual, Calibration Certificate and  a set of 4 Wire Kelvin Handheld Probes or 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 620LKtm 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.

Unlike Our Competition, the compact AMPTEC 620LK others doesn't need or use a  Heavy Weight Battery Pack  

Any brand of "AA" Alkaline or optional rechargeable NiMH "AA" battery will work

Unlike some of our competition's, heavy weight bond meters with "lead acid battery - bowling ball" equivalent mass of 10 LBS or more . . .  The AMPTEC 620LK Bonding Ohmmeter (3 LBS vs 12 LBS) does not use or need a heavy weight lead acid based battery pack, like those found on older model bonding ohmmeters. The compact AMPTEC 620LK is powered by 4 ea "AA" alkaline or can be optionally powered by any set of 4 ea. standard "AA" NiMH Rechargeable batteries. The lighter compact nature of the AMPTEC 620LK Safety Bonding Milli-Ohmmeter makes it ideal for carrying out to the flight deck or extended multiple bond measurements for (Aircraft) production use. Imagine having to wear/hold our competitors (12 LB) Bonding Ohmmeter while reaching up with the probes to make a difficult to reach spot for a bond measurement on an aircraft. You get the picture - The compact AMPTEC 620LK wins handsdown for ease of use and accuracy.      

Integrity of Measurement and an instrument's accuracy is important to us. It should be important to you. To provide proof, in writing, that an instrument is truly accurate, many instrument companies charge extra for a new instrument's calibration certificate, Not at AMPTEC RESEARCH. All new AMPTEC instrumentation comes with a U.S. N.I.S.T. traceable calibration Certificate, good for 1 year, at "No Extra Charge". After the 1 year calibration interval has expired on your AMPTEC meter, we can still re-certify the product for you. Contact our customer service department for details.

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 620LK 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.)