X3T9.2/92-035 Rev 2
To:       X3T9.2 Committee (SCSI)

From:     George Penokie (IBM)
          Claude Mosley

Date:     April 29, 1992

Subject:  SCSI-3 P-Connector requirements



The following changes, if accepted into the SCSI-3 SPI standard,
would result in a more reliable connector system.  The changes
listed are a result of the connector SWIG held on 3/16 in San
Diego.  Reference the SPI March 13 rev for sections and figures.

Section 5.3

Add the following paragraph to the end of this section:
     The P-connector system shall be a multi-wipe design with
     contact geometry and normal force sufficient to pass the
     following test:
          1)   Initial contact measurement is made using the test
               procedure for Low Level Contact Resistance as
               defined in EIA 364-23A
          2)   50 mating/unmating cycles
          3)   Contact resistance is measured (this is an optional
               step)
          4)   Perform flowing mixed gas test per IEEE 1156.2 on
               mated connectors
          5)   Measure contact resistance and if there is a delta
               less that 15 milliohm then the connector passes

     The resistance shall be measured using a 4 point dry circuit
     method directly across the mated contact.

Figure 2

Change the note to read as follows:
     NOTE: Dimension B8 and B10 are opening in the dielectric.  The
     socket contacts (not show) are to be centered within the
     opening.

Figure 3

Add A16 to the table as follows:
     A16    1.016 +/-0.254 R  0.040+/-0.010 R

     Note: the dimensions are the same for both 50 and 68 pin
connectors.

Figure 4

Change the note to read as follows:
     NOTE: Dimension B8 and B10 are opening in the dielectric. The
     socket contacts (not show) are to be centered within the
     opening.

Figure 5

Add A19 to the table as follows:
     A19    1.016 +/-0.254 R  0.040+/-0.010 R