Date: July 16,1992                            X3T9.2/92-155 Rev 0

    To: X3T9.2 Committee (SCSI)

    From: Claude Mosley (IBM)
          George Penokie (IBM)

    Subject: Connector Requirements

    The P-connector system shall be a multi-wipe design with contact
    geometry and normal force sufficient to pass the following test:

    1-Measure contact resistances of the connectors being evaluated
      using a test procedure for low level contact resistance.  Use
      EIA 364-23A (Low Level Contact Resistance Test Procedure For
      Electronic Connectors) as a reference procedure.  Record
      measurements as initial contact resistances.

    2-Unmate and mate connectors 50 cycles.

    3-Remeasure contact resistances as per step 1 (optional.

 |  4-Expose mated connectors to mixed flowing gas (MFG) consisting of
 |    10 PPB of chlorine, 10 PPB of hydrogen sulfide, 200 PPB of sulfur
 |    dioxide, and 200 PPB of nitrogen dioxide for 20 days at 70%
 |    relative humidity and 30 degrees Celsius.  Use ASTM B-827
 |    (Standard Practice for Conducting Mixed Flowing Gas
 |    Environmental Tests) as a reference procedure.

    5-Remove connectors from MFG, remeasure contact resistance per
    step 1.  Compare resistance to measurements in step 1.  Any
    contact which has a increase of 15 milliohms or greater is a
    failure.

    The remaining is for informational purposes and need not go into
    the standard.

    Mixed flowing gas tests

    IEC
     -20 PPB Chlorine
     -200 PPB Nitrogen Dioxide
     -100 PPB Hydrogen Sulfide
     -75% Humidity and 30 Degrees Celsius
     -20 days exposure

    IEEE
     -10 PPB Chlorine
     -200 PPB Nitrogen Dioxide
     -200 PPB Sulfur Dioxide
     -10 PPB Hydrogen Sulfide
     -75% Humidity and 30 Degrees Celsius
     -20 days exposure

    IBM
     -3 PPB Chlorine
     -500 PPB Nitrogen Oxide
     -300 PPB Sulfur Dioxide
     -40 PPB Hydrogen Sulfide
     -70% Humidity and 25 Degrees Celsius
     -12 days exposure

    Batelle Labs
     -No Sulfur Dioxide