NEPS Nitrogen and Dry Gas Purging Systems

Nitrogen is generally a reliable dry gas, which is economic, safe (when handled properly) and chemically inert with most metals and materials.

Bottled nitrogen is often specified as dryer than 2 ppm (parts per million) equivalent to a dew point of -94°F (-70°C). The gas source for drying should always be validated before use. As a rule of thumb the gas must be at least 10°C lower than required purge dryness.

• Molecular Weight: 28.01
• Boiling Point: -319.9°F (-195.5°C ) at 14.7 psi (101.3 kPa)
• Specific Volume: 13.72 ft.3 lbs.-1 (0.855 m3 kg-1 at 68°F (20°C), 14.7 psi (101.3 kPa)
• Critical Temperature: -232.5°F (-146.95°C)
• Critical Pressure: 493 psi (3,400 kPa)
• Heat Capacity: 0.249 BTU lbs.-1 °F-1 (1,040 Jkg-1 K-1) at 77°F (25°C), 14.7 psi (101.3 kPa)

Leak testing can be carried out to ensure the suitability of the equipment for pressurized purging. The default pressure test setting is 2.5 psi.

Leak testing with the NEPS nitrogen purge system is a simple operation and has a sensitivity that is related to pressure degradation against time. The NEPS nitrogen purge system has a display resolution of 0.01 psi allowing users to achieve high sensitivities depending on the monitored time for the equipment under test to degrade from the initial test pressure.

The equipment volume must be considered when calculating the actual leak rate.

60 Minutes to degrade by 0.01 psi 1,000 cc volume = 1.9 x 10-4 cc/second 10,000 cc volume = 1.9 cc x 10-3 cc/second

CAUTION: Leak testing must be conducted with a stable/constant ambient/equipment temperature. A variation of 3.6°F (2°C) can cause up to a 0.1 psi change in pressure.

Yes. It is available in a 19″ rack-mounted version, NEPS 1900 Racked, for use in automated test situations.

The NEPS 1000 comes standard with male and female quick disconnect. The female will need to be adapted to your nitrogen line and has a 1/4″ NPT female thread to connect to.

The standard NEPS 1000 and NEPS 1900 rack-mount models require nitrogen or other dry air sources. The NEPS 1000 pumped has a bed of molecular sieve desiccant that dries the incoming air prior to sending it into your enclosure and does not require a dry air source. This is particularly useful in field use where it might be cumbersome to have a bottle of high-pressure nitrogen on hand. However, periodically, the molecular sieve desiccant will need to be replaced. We carry a full line of desiccant products and can supply replacement desiccants for NEPS units.

No. The NEPS 1000 can be used with nitrogen, dry air, argon, and sf6 gasses. It should be noted that dry gasses are available in varying qualities and levels of dryness. (no flammable gasses should be used)

The NEPS will display a dew point range of +20°C (+68°F) to -80°C (-112°F).

No. After initial setup, the NEPS 1000 will automatically stop the dry gas cycling when the air stream leaving the equipment reaches a preset dew point temperature. With the addition of a remote sensor, the dew point stat feature of the NEPS 1000 will then resume dry gas cycling after the dew point temperature has degraded to a predetermined amount.

Yes. After repeated cycles, it will become apparent when the moisture has been removed from the hygroscopic materials in the equipment. It is a common misconception that the majority of the moisture in sealed equipment is contained in the empty volume of air. In fact, the majority of the moisture is contained in hygroscopic materials, such as electrical boards and plastic components.

Yes. You can lease a NEPS unit so you can test it for your specific applications, contact us for more information.