AMPTEC Research · Intrinsically Safe Igniter Testers
620BA
Ultra-safe bridge-wire resistance measurement with a failsafe 8 mA current limit for electro-explosive devices
The Amptec 620BA is the igniter tester you reach for when the resistance you need to read sits inside a detonator, a squib, a flare or a bridge wire. A failsafe current-limiting resistor network holds the test current below 8 mA no matter how the circuit fails. A 4 1/2 digit LED display and ±0.02% of reading accuracy on the low ranges make it a standard bench and field meter for ordnance, aerospace and defense labs. Evencat is the sole distributor for AMPTEC Research in Taiwan.
Overview
The 620BA belongs to the 620 series, the family of igniter testers built on a design approved by the USAF for electro-explosive device testing. What matters in this class of instrument is not the readout but what the meter can never do: the failsafe resistor network guarantees that current through the device under test stays under 8 mA even with an internal fault, so a sensitive detonator or bridge wire is never fired by the measurement itself. Four ranges cover 2 Ω, 20 Ω, 200K Ω and 20M Ω, with 100 uΩ resolution on the lowest range and a base accuracy of ±0.02% of reading. That spread handles low-resistance bridge wires at one end and insulation checks at the other. The meter reads out on a 4 1/2 digit LED display, connects through banana jack binding posts, and runs from four rechargeable 5AHr NICAD batteries, so it works equally well on a bench or at an ammunition site. It is UL-913 compliant and built under ISO 9001:2015. Before ordering, decide whether you need the RS232C interface or the isolated AC supply for a fixed test station; both are factory options.
Key specifications
| Display | 4 1/2 digit LED |
|---|---|
| Resistance ranges | 2 Ω / 20 Ω / 200K Ω / 20M Ω |
| Best resolution | 100 uΩ (2 Ω range) |
| Base accuracy | ± .02% of reading & ± .05% of range |
| Failsafe test current | 8 mA (failsafe) |
| Nominal test current | 5 mA (2 Ω / 20 Ω ranges) |
| Update rate | 3 readings/second |
| Open-circuit voltage | 1.6 VDC |
| Maximum input voltage | 250 VDC |
| Power | 4 rechargeable 5AHr NICAD batteries |
| Operating temperature | 0° to 50° C |
| Dimensions | 9.75″ x 10″ x 3.25″ |
Features
Failsafe current limiting
A current-limiting resistor network keeps the test current below 8 mA under every fault condition, so sensitive detonators and bridge wires cannot be fired by the meter.
Intrinsically safe by design
Built for ultra-safe resistance checks on bridge wires, detonators, flares and other electro-explosive devices, and compliant with UL-913 for intrinsic safety.
Four resistance ranges
2 Ω, 20 Ω, 200K Ω and 20M Ω ranges with 100 uΩ best resolution, covering low-resistance bridge wires through to high-resistance insulation checks.
Accurate LED readout
A 4 1/2 digit LED display with ±0.02% of reading accuracy and 3 readings per second gives a clear, stable value without waiting.
Rechargeable battery power
Four internal 5AHr NICAD batteries and banana jack binding posts make it a carry-anywhere meter for the lab and the field.
Typical applications
Aerospace manufacturing
Acceptance testing of rocket and spacecraft ignition systems
On rocket motor and satellite separation-device production lines, engineers use the 620BA to measure the resistance of squibs and bridge-wire initiators and confirm each part sits within its design tolerance. The failsafe circuit caps the test current at 8mA, removing the risk of firing a device with the measurement current.
Ordnance safety
Continuity safety checks on military munitions and explosives
Ordnance technicians at bases and ammunition plants use the 620BA to verify continuity on initiators, flares and pyrotechnics during explosive handling procedures. Its UL-913 intrinsic safety compliance and its lineage from a USAF Non-Nuclear Munitions Safety Board approved design allow it to be used where flammable gas or dust may be present.
Quality assurance
Outgoing electrical QC at a pyrotechnic component plant
At the final electrical inspection station, makers of pyrotechnic devices use the four ranges of the 620BA (2Ω, 20Ω, 200KΩ, 20MΩ) to sample bridge wires and ignition heads of different nominal resistance at ±0.02% accuracy, building traceable batch records that meet ISO 9001:2015 quality system requirements.
Options and configuration
Tick the options you need. We compile the configuration into a list and carry it into the quote form.
Standard equipment (included)
Hardware options
Downloads
Need pricing, specifications or lead time for 620BA?
Also available for rent: 620BA is part of the AMPTEC rental program, for project peaks, calibration backup and pre-purchase trials. Rental inquiry →