High voltage power supply standard

The popular VPX for high performance computing is a multifaceted, multilayered family of standards covering everything from modules to chassis to systems to architectures. The range of applications targeted by this technology require many dot standards to cover all cases. A recently fast-tracked standards effort illustrates type of work underway at VITA to make the VPX technology more robust.

Power supplies can be plug-in modules to VPX systems. This requires connector technology for both the power supply modules and the reciprocating backplanes. Sealed connectors are typically required for high voltage applications in harsh environments. The recently accredited ANSI/VITA 86-2019 High Voltage Input Sealed Connector Power Supply standard defines an environmentally sealed connector pair, which is compatible with the backplane footprint as defined in the ANSI/VITA 62.0 Modular Power Supply Standard for 3U power supplies operating in harsh environments operating off a high voltage input.

The modules defined in ANSI/VITA 86 rely heavily on the VITA 62 standard and are further adapted for applications where VPX power supplies are used in harsh airborne environments. Power supply vendors are expected to comply with VITA 47 environmental considerations to ensure survivability in the harsh environment of many of the deployments they will encounter. This makes the VITA 86 efforts ever more important in addressing these challenging environmental conditions when using VPX technology in military applications.

VITA 86 defines both the mechanical and electrical requirements for commercial-off-the-shelf (COTS) modules intended for creating modular power supplies. The primary focus is to support VPX and OpenVPX standards when designing systems meeting ANSI/VITA 47 environmental conditions with COTS modules that are compatible with the VPX specifications.

As part of the work to create VITA 86, a new connector system was defined, optimized for the harsh environmental needs of VITA 47. This connector mechanically fits within the envelope defined in VITA 62 and VITA 48.2 for 3U Plug-In modules. It also supports the electrical requirements as defined in those standards. This facilitates the production of backplanes and allows system designers to define where and how many power supply modules are to be used within any given system without re­designing the backplane.

The Rantec Power Systems, Inc. Ruggedized Sealed Power Connector (RC-V86) family of high-power military interconnect systems is designed for the harshest environments in a 3U form factor needing higher input voltages up to 500VDC, while withstanding the effects of harsh airborne environments including altitude, corrosion, shock, and vibration. The RC-V86 (Figure 1) is a reliable interconnect solution with low contact resistance and capable of withstanding a high number of mating cycles. This connector was selected as the reference connector for the VITA 86 standard.

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Figure 1: The Rantec RC-V86.
(Click graphic to zoom)
 

Environments:

  • Operating Temperature: -55 °C to +85 °C per MIL-STD810G, Method 501.5/502.2, II
  • Storage Temperature: -65 C to +125 °C per MIL-STD-810G, Method 501.5/502.2, I
  • Temperature Shock: -65 °C to +125 °C per MIL-STD-810G, Method 503.5, I-C
  • Operational Altitude: -1,500ft to 70,000ft per MIL-STD -810G, Method 500.5, II
  • Mating Durability: 500 mating cycles
  • Shock: Sustain up to 300G 3ms half-sine shocks per MIL-STD-810G, Method 509.5
  • Vibration: 43.92 GRMS 15-2,000HZ random vibration per MIL-STD-810G, Method 514.6, I
  • Salt fog for 500 hours per MIL-STD-810G, Method 514.6, Procedure I
  • Fluid contamination per MIL-STD-810G, Method 504.1,
  • Humidity per MIL-STD-810G, Method 507.5, II, and relative humidity of 100 percent

The initial effort focused on 3U VPX modules, but future updates to the standard are under consideration for 6U VPX power supply modules. VPX considers and supports a wide range of environmental and performance characteristics. VITA 86 helps in providing the necessary standards to meet those characteristics.

For additional information please visit, www.rantec.com or contact Phil Keohen at pkeohen@rantec.com or (805) 596-6015.