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Home | Products | Squib Testing | 620A-4 | Digital Failsafe Ohmmeter

The 620A-4 Igniter Circuit Tester is our flagship ohmmeter. A failsafe and portable digital ohmmeter specifically designed for ultra-safe resistance testing on squibs, flares, bridge-wire, and other explosive devices, the 620A-4 was the first we designed in our long line of intrinsically safe instruments. Capable of making highly accurate resistance measurements from 20 Ω to 20 KΩ, this ohmmeter has a proven track record of durability: with 20+ year old units still being used in the field today. This unit has been designed to never have a current level that exceeds 8 mA – the cornerstone of our failsafe design. The 620A-4 is compatible with many convenient modifications, such as OP-247 Optically Isolated Power (enabling the unit to run on AC power rather than batteries) or OP-232 RS232C Interface (enabling the unit to communicate with your computer via an RS232 port), allowing you to fully customize your instrument and cater it to your specific needs. Due to its intense self-safety design and numerous certifications, the 620A-4 failsafe ohmmeter is the industry standard for military programs in need of igniter testing.

 

The 620A-4 safety ohmmeter has been approved by the USAF Non-Nuclear Munitions Safety Board for usage on all non-nuclear munitions, and independently certified to meet Mil. Std. 810 Mtd. 511 for usage in fuel-filled environments. Amptec is an ISO 9001:2015 certified company, ensuring each instrument is manufactured to the highest quality standard.  Every instrument made is designed and manufactured in the USA, comes with an extensive one-year warranty, and an N.I.S.T. calibration certificate with data at no extra charge.

 

Description

 

Range, Resolution, Accuracy, and Current Levels

Range20 Ω200 Ω2K Ω20K Ω
Nominal Current5 mA.5 mA50 uA5 uA
Failsafe Current8 mA8 mA8 mA8 mA
Resolution1 mΩ10 mΩ100 mΩ1 Ω
Accuracy± .02% of reading & range± .02% of reading & range± .02% of reading & range± .02% of reading & range

 

General Specifications

Display4 1/2 digit LEDTerminalBanana jack binding posts
Storage Temperature Range-20° to 70° COperating Temperature Range0° to 50° C
Dimensions9.75″ x 10″ x 3.25″Weight (Standard Version)3.5 lbs.
Power4 ea rechargeable 5AHr NICAD batteriesMax. Input Voltage250 VDC
Open Circuit1.6 VDCMax. Internal Voltage4.8 VDC
Update3 readings/secondTemperature Coefficient± .002% per 1° C

For further specifications (such as the various modified versions of this product) contact us or see the product data sheet.

Additional information

Weight5 lbs
Dimensions36 × 36 × 36 in
Model

Commercial, NSN

Contact To Purchase
  • Specifications
  • Ordering Information
  • Downloads

 

Range, Resolution, Accuracy, and Current Levels

Range20 Ω200 Ω2K Ω20K Ω
Nominal Current5 mA.5 mA50 uA5 uA
Failsafe Current8 mA8 mA8 mA8 mA
Resolution1 mΩ10 mΩ100 mΩ1 Ω
Accuracy± .02% of reading & range± .02% of reading & range± .02% of reading & range± .02% of reading & range

 

General Specifications

Display4 1/2 digit LEDTerminalBanana jack binding posts
Storage Temperature Range-20° to 70° COperating Temperature Range0° to 50° C
Dimensions9.75″ x 10″ x 3.25″Weight (Standard Version)3.5 lbs.
Power4 ea rechargeable 5AHr NICAD batteriesMax. Input Voltage250 VDC
Open Circuit1.6 VDCMax. Internal Voltage4.8 VDC
Update3 readings/secondTemperature Coefficient± .002% per 1° C

For further specifications (such as the various modified versions of this product) contact us or see the product data sheet.

Pricing Request

    Downloads

    Data Sheet Manual