AMPTEC Research · Intrinsically Safe Voltmeters
620EXV
Ultra-safe portable digital voltmeter for explosive atmospheres
620EXV is a battery-powered portable digital voltmeter that reads 0 to 30V RMS, built to check firing circuits and related system wiring for voltage. It is certified to MIL-STD-810 Method 511 and UL-913 for use in explosive atmospheres, and red and green LEDs show at a glance whether the voltage is under the set threshold. Engineers in defense, ordnance and aerospace who need an intrinsically safe voltage check choose it for exactly that reason.
Overview
AMPTEC 620EXV is an ultra-safe portable digital voltmeter with a 30V RMS full-scale range, 10mV resolution and a 4-digit LCD that refreshes 3 times per second. It exists to check firing circuits and the wiring around them for voltage before anyone touches them. GO and NO-GO LEDs (threshold adjustable, 60mV by default) show immediately whether the reading is within the safe limit, and the LEDs resolve the 60mV decision better than the four-digit display does. 620EXV is certified to MIL-STD-810 Method 511 and UL-913, is built under ISO 9001:2015, and is classed as an Arc Flash Safe device for explosive atmospheres. The rugged portable design (NSN 6625-01-595-2019) is used across defense, ordnance and aerospace wherever an intrinsically safe voltage measurement is required. Note that the batteries are rechargeable and the charger is not itself rated for hazardous areas, so plan charging in a safe location.
Key specifications
| Measurement range | 30V RMS |
|---|---|
| Resolution | 10mV |
| Accuracy | ±10% |
| Display | 4-digit LCD, 3 updates per second |
| GO indicator | reading < 60mV (adjustable) |
| NO-GO indicator | reading > 60mV (adjustable) |
| Power | 4 AA NiMH rechargeable cells (1.2 V); alkaline cells must not be fitted |
| Low battery indication | "LO BAT" |
| Dimensions | 7.56″ x 7.69″ x 3″ |
| Weight | 5 lbs net / 7 lbs shipping |
| Operating temperature | -20° to 55°C |
| Storage temperature | -40° to 70°C |
Features
Intrinsically safe design
Certified to MIL-STD-810 Method 511 and UL-913 and classed as an Arc Flash Safe device, so it can be used in explosive atmospheres.
Firing circuit voltage checks
Built to measure voltage on firing circuits and related system wiring, with a 30V RMS range and 10mV resolution.
GO / NO-GO at a glance
Red and green LEDs show whether the voltage is under the threshold; the threshold is adjustable (60mV by default), so the call is quick and unambiguous on site.
Portable battery power
Runs on 4 AA NiMH rechargeable cells, weighs 5 lbs and shows a "LO BAT" warning, easy to carry for field work.
Wide temperature range
Operates from -20° to 55°C and stores from -40° to 70°C, so it keeps working in harsh defense and aerospace field conditions.
Typical applications
Firing systems
Firing circuit voltage pre-check
Before assembling or disarming pyrotechnic devices, technicians use 620EXV to confirm the voltage on firing lines and related system wiring. The green GO LED shows at once that the line is under the safety threshold (60mV by default), so residual voltage cannot trigger an initiator during the work that follows.
Explosive atmospheres
Intrinsically safe measurement in hazardous gas atmospheres
Where flammable gas or vapor is present, such as propellant loading stations, munitions storage or ground support equipment bays, the 620EXV UL-913 intrinsic safety certification and MIL-STD-810 explosion-proof design keep the meter from becoming an ignition source. Electrical staff run voltage checks without purging the area first.
Aerospace maintenance
Incoming electrical checks on flight vehicles
Before overhauling the electrical systems of a flight vehicle, including UAVs and rockets, maintenance shops use 620EXV to confirm that safety-critical circuits such as ejection seats and emergency cutoffs are fully de-energized. The 4-digit LCD reading and the dual LED indication give QA staff a record for inspection evidence, in line with NASA and USAF procedures.
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)
Probe and lead options
Cases and consumables
Downloads
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