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By Ron Williams, 10-3-04
  • The C.H.M. has two 1401 systems:
    One Is a U.S. ( 60 Hz ) system on the tour floor.
    The other is a German (50 Hz ) system in the Restoration Lab.
  • I will refer to them as "tour" and "lab" systems or machines.
  • The restoration team is charged with making the lab system operational.
  • A lot of inspecting, cleaning, and bench testing has been done. With a few bugs repaired.
  • The 1401 (CPU ) , 1406 ( Additional core) ,1403 ( Printer ) are or soon will be ready for A.C. power.
  • The 729s ( Five tape drives) have not seen much attention lately due to team vacations.
  • They ( 729s ) are still in mechanical repair mode.
  • The 1402 ( Reader/punch ) is in need of significant electrical and mechanical safety and functional repair.
  • The tour 1402 is temporarily in the restoration lab for comparison and parts swapping.
  • All machines in the system rely on the 1402 for their primary power.
  • The power supply logics that came with the lab 1402 do not reflect the machine.
    I.E. Circuit breakers 1 and 2 do not exist in the 1402.
    Power for 729s is not allocated per logics.
    Plus/minus 3v. power supply is missing and wiring is taped back.
  • There is some very sub-standard, non-IBM wiring in the lab 1402 power area.
  • There is no power cable for the 1402.
  • Many thanks to Jim Yee ( electrician ) for getting power to the Elgar ( 50 Hz converter) and helping us check it out.
  • The logics and phase strapping in the 1402 indicate it wants WYE configuration.
  • With my limited knowledge of three phase power, I am unclear whether the Elgar can put out the needed voltage.
  • IBM specs call out "Three Phase 60 Amp Service" for this system configuration.
    I believe that means a huge 4 pin connector and a 4 conductor plus ground,cable. Unless/until the 729s are on line, we won't need near that much power.
  • The Elgar has a 30 Amp outlet on it. This could power the 1401,1402,1403,1406.
  • I would like the team to have permission to take functional parts from the tour 1402 as needed to bring the lab 1402 up to an operational and safe level.
    This could include:
    Taking CB-1*
    Taking CB-2*
    Taking at least 1 power cable harness
    Taking Contactor 1*
    Taking Contactor 2*
    Design, make,and install one or more plastic shields to cover
    exposed high voltage areas.
    *..This would also put the 1402 in spec; so power to the 729s can be shut off at will.

    Note...l/we don't want to do the above without the help and blessing of the 1402 team ; but they are very scarse, and the 1402 is a bottleneck.

Ron Williams