UHP Dual Switch Gauge

Certain industrial processes require mixing gases or switching several media. This action is particularly important in the following sectors:

  • Semiconductors, photovoltaic, and flatscreen production
  • Medical gases
  • Gas distribution systems
  • Life safety systems
  • Aeronautics and aerospace

Many applications in these industries have high purity (HP) and ultra-high purity (UHP) standards. This means that pressure measuring and switching instrumentation must also comply with stringent requirements for accuracy, media resistance, and leak integrity. On top of these compliance demands is limited space for two pressure switches.

WIKA’s UHP dual switch gauges meet all the above criteria for cleanliness, compliance, and compactness.

WIKA’s UHP Gauges with Two Switch Contacts

Our ultra-high purity gauges have two independent UHP switches that occupy the same dimensions as a single pressure switch. These Bourdon tube pressure gauges – models 230.15 and 230.25, for example – come with two SPDT (single pole double throw) reed switches that can be configured as NC (normally closed) or NO (normally open). Switching points can also be set or changed on site.

Other benefits of WIKA’s UHP dual switch gauges:

1. Clean design and fabrication

The pressure-measuring element has a crevice-free design, and the case and all internal parts are electropolished to ensure clean operations. After assembly, all UHP gauges undergo a helium leak test. To ensure that they meet UHP standards, the gauges are assembled, tested, and packed in class 100 cleanrooms. These instruments comply with SEMI standards, FM (USA), ATEX (Europe), and IEC Ex (International) non-incendiary guidelines.

2. Robust construction

WIKA’s UHP dual switch gauges have a stainless steel movement and are housed inside a stainless steel case rated IP54/NEMA 3. The high-quality, corrosion-resistant materials make this switch gauge suitable for poisonous/toxic, flammable, and corrosive media, whether it’s gaseous or liquid.

3. Gall-resistant connectors

The nuts in UHP gauges’ process connectors are typically made of stainless steel. However, most SS alloys will gall over time. Silverplating the threads will reduce or prevent galling, but silver tends to flake with repeated tightening and loosening, resulting in particle contamination.

This problem of silver flaking is why WIKA has transitioned to UNS S21800 in the nuts of our UHP process connectors. This particular stainless steel alloy has inherent lubricity and gall-resistant characteristics, which eliminates the need for silverplating. UNS S21800, which goes by the trademarked name of Nitronic 60, is standard on our female face-seal process connectors and is an option for male face-seal process connectors.

Applications of UHP Dual Switch Gauges

WIKA’s dual switch gauges are found in a variety of UHP applications. They can be set up to detect and alert users of low- or high-delivery pressure conditions in a system. These pressure instruments are also ideal for control, such as automatic switchovers or process shutdowns. Many of our customers use our HP and UHP gauges to monitor and control the operation of gas cylinders, gas panels and cabinets, valve manifold boxes, and gas distribution systems.

Our UHP dual switch gauges solve the problem of limited space in medical gas delivery and other processes, such as semiconductor, photovoltaic (PV) solar panels, and flatscreen fabrication. What’s more, as a two-in-one unit, a dual switch gauge simplifies application design and reduces inventory needs.

Contact our semiconductor and pressure specialists for more information about our complete line of HP and UHP pressure solutions.