AMPTEC Research · Igniter Testers
620VL-T
Wide-range intrinsically safe igniter tester with test current never above 8 mA
The AMPTEC 620VL-T is a failsafe ohmmeter for ultra-safe resistance testing of bridge-wires, squibs, flares and other explosive devices. A failsafe current-limiting resistor network keeps the test current at or below 8 mA, and five ranges span 20 ohm to 2 Mohm, so one instrument covers low-resistance bridge-wires and high-resistance firing circuits alike. It descends from the 620A-4 approved by the USAF Nonnuclear Munitions Safety Board and is a standard tool for igniter testing in defense, aerospace and munitions work. Evencat is the sole distributor for AMPTEC in Taiwan.
Overview
The AMPTEC 620VL-T wide-range intrinsically safe igniter tester was developed for ultra-safe resistance measurement of bridge-wires, squibs, flares and similar explosive devices (NSN 6625-01-721-7869). At its core is a failsafe current-limiting resistor network: even with a fault inside the instrument, test current cannot exceed 8 mA, so a sensitive electro-explosive device is not at risk from the measurement itself. Five ranges, 20 ohm, 2 kohm, 20 kohm, 200 kohm and 2 Mohm, use 4-wire Kelvin terminals to cancel lead resistance and a 4-1/2 digit LED display for the readout. Accuracy is +/-0.02% of reading and range on the three lowest ranges, easing to +/-0.05% on 200 kohm and +/-1% on 2 Mohm. The 620VL-T is derived from the 620A-4 that the USAF Nonnuclear Munitions Safety Board approved, is UL-913 compliant and is built under ISO 9001:2015. Rechargeable NICAD batteries make it as usable in the field as on the bench. When ordering, decide whether you need RS232C (OP-232) or an isolated analog output (OP-500) for logging, and whether the unit will live in a rack (OP-519S/D).
Key specifications
| Resistance ranges | 20Ω, 2KΩ, 20KΩ, 200KΩ, 2MΩ |
|---|---|
| Nominal current | 5mA down to 0.05µA (by range) |
| Failsafe current | 8mA down to 0.15µA (by range) |
| Resolution | 1mΩ to 100Ω (by range) |
| Accuracy | ±0.02% of reading and range (20Ω, 2KΩ, 20KΩ); ±0.05% of reading and range (200KΩ); ±1% of reading and ±0.2% of range (2MΩ) |
| Temperature coefficient | ±0.002% / 1°C |
| Display | 4½ digit LED |
| Terminals | 4-wire Kelvin |
| Maximum input voltage | 250 VDC |
| Maximum internal voltage | 4.8 VDC |
| Update rate | 3 readings/second |
| Power | 4 rechargeable 5AHr NICAD batteries |
Features
Failsafe current limiting
A failsafe current-limiting resistor network holds test current at or below 8 mA, so bridge-wires, squibs and explosive devices can be measured without risk of firing.
Wide resistance coverage
Five ranges from 20 ohm through 2 kohm, 20 kohm and 200 kohm to 2 Mohm cover most igniter and electro-explosive device resistances with one instrument.
4-wire Kelvin measurement
Kelvin terminals remove lead and contact resistance from the result, supporting +/-0.02% of reading and range on the low ranges.
4-1/2 digit LED display
The LED readout updates 3 times a second and reads directly, so a go/no-go call on the line is quick.
Battery-powered and portable
Four rechargeable 5AHr NICAD cells and a compact case suit both laboratory benches and field work.
Military and safety certifications
Derived from the USAF Nonnuclear Munitions Safety Board approved 620A-4, UL-913 compliant and built under ISO 9001:2015.
Typical applications
Aerospace and defense
Pre-launch resistance verification of pyrotechnic devices
Before a missile, rocket or munition is committed to a mission, military technicians measure squib and bridge-wire initiator continuity with the 620VL-T to confirm the resistance matches the design value. The failsafe limit of 8 mA guarantees the check itself can never cause an initiation, protecting both crew and hardware.
Pyrotechnic manufacturing
End-of-line bridge-wire resistance sampling
Manufacturers of pyrotechnics and industrial blasting products use the 620VL-T low 20 ohm range (+/-0.02%) at the end of the line to sample bridge-wire resistance lot by lot, screening out units that drift outside specification so every shipped batch fires consistently.
Hazardous sites
Maintenance checks of flares and pyrotechnics inside ATEX hazardous areas
Carrying EU ATEX approval (EEX-9B-IIC-T4), the 620VL-T can be used where flammable gases or vapors may be present, letting maintenance crews at naval bases, petrochemical sites and field depots survey flares and smoke devices in place instead of moving them out of the hazardous area first.
Options and configuration
Tick the options you need. We compile the configuration into a list and carry it into the quote request form.
Standard equipment (included)
Hardware options
Downloads
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