3B1 Power Supply Summaries

Wed Feb 14 14:16:57 AEST 1990

In article <87.25d7fc59 at venus.ycc.yale.edu>, newman at suncis.ycc.yale.edu (Andrew Newman) writes:
> Greetings:
> 
> There has been a lot of talk lately about 3B1 power supply availability. 
> As I understand it Halted no longer has any of the 3B1 pwr. supplies left 
> in stock.  Does anyone have a source for these items?  If not, does anyone
> wish to offer a voltage pin-out for the power supply connector?  I figure
> in the worst case I could kludge up some sort of external power supply if
> mine were to fail (it hasn't yet!).
> 
> Finally, what are the odds of using a 7300 power supply in a 3B1?  Does anyone
> actually know what the differences are?
> 
	Yes, I have a couple of 3b1 PSUs stashed in my garage, I thought 
ahead and bought ahead. I could part with one or two at a 
suitably exorbitant rate.

	Furthermore, I glanced through my files and found some info that 
may be pertinent:

 I just got this mail message from Thad Floryan (thad at cup.portal.com):

 ===================================================================
                       UNIXPC POWER SUPPLY PINOUTS
                             18-Pin Connector
  .
  .
  .
  |       O  O     O  O O  O            O   O     O   O  O
  |     BLK  [  YELLOW  ]  BLK          [RED]     [  BLK ]
  |  +------------------------------------------------------+
  |  | O  O  O  O  O  O  O  O  O  O  O  O  O  O  O  O  O  O |
  |  +------------------------------------------------------+
  |   18          J1        *-----------*     *---------* 1
  +------------------------------------------------------------...

  +5 VDC is commoned to pins 2, 4, 6, 8 and 10
   is also commoned to the two (2) holes marked [RED]

  +12 VDC is commoned to pins 12, 14 and 16
   is also commoned to the four (4) holes marked [YELLOW]

  -12 VDC is available at pin 18

  GROUND is commoned to pins 1, 3, 5, 7, 9, 11, 13, 15 and 17
   is also commoned to the five (5) holes marked [BLK]
 ------------------------------------------------------------------
                         POWER SUPPLY RATINGS
  Power Systems, Inc.
 System     Model Number Convergent Part No. +5 V +12 V -12 V
 ------ ------------------- -------------------- ---- ----- ------
  3B1     PS 1610-1  D-65-00056-1, Rev. B 20 A 5.0 A 300 mA

  3B1     PS 1610-1  D-65-00056-01, Rev. A 20 A 5.0 A 300 mA

 7300     PS 1569  D-65-00042-00, Rev. E 20 A 3.5 A 100 mA

 7300     PS 1569  D-65-00060-01/A  20 A 3.0 A 300 mA

 The 3B1 supplies have the AC rating: 90-130 VAC, 58-63 Hz, 245 W
 The 7300 supplies have the AC rating: 90-130 VAC, 58-63 Hz, 195 W

  Lenny Tropiano            ICUS Software Systems      [w] +1 (516) 589-7930
  lenny at icus.islp.ny.us     Telex; 154232428 ICUS      [h] +1 (516) 968-8576
  {ames,pacbell,decuac,hombre,sbcs,attctc}!icus!lenny     attmail!icus!lenny
 ------ ICUS Software Systems -- PO Box 1;  Islip Terrace, NY  11752 ------

Re: Wolf Paul's questions  (my answers posted since  they seem to 
be of general interest) ...

Q: "1. Does a 3b1 PS fit into a 7300?"
A:   It  should.  Both  supplies  have  the  same  mounting  hole 
     arrangement  and appear  to be the same height,  so vertical 
     clearance should be OK for either a 7300 or 3B1 case.

Q: "2.  Are  there 220VAC  or  240VAC versions  of  these  power 
     supplies  available?   (I just  bought  a 7300 and it  looks 
    like I will be moving to Europe at year's end.)"
A:  The  AT&T UNIX PC REFERENCE  MANUAL  (the book with  all  the 
    schematics)  has an appendix "International Version" in which 
    is  stated: "The electrical specification  for this equipment 
    is 220-240 volts."
    In  general,  many  switching  power  supplies have  a single 
    jumper  that  permits  primary  operation on either 120VAC or 
    240VAC. 

Having just returned from the West Coast Computer Faire in which 
I  was  demo'ing  the UNIXPC  for  the past 3 days  in  the  AT&T 
Computer Users' Group booth, I'm pooped and unable to open one of 
the  machines  right  now  to see if  there  IS  a jumper  on the 
UNIXPC's power supply.

    HOWEVER,  rest assured that you  can operate  your UNIXPC  in 
Europe  using a step-down transformer  (external device), and  my 
original  doubts concerning problems  with a line frequency of 50 
Hz have been cast aside due to the successful operation of  a 3B1 
by  Jim  Sanchez of SYTEK  in  Brussels since January  1988;  his 
system  has been (and still is!) operating 24 hours/day. If you'd 
like Jim's email (uucp) address (via SYTEK in Mountain View, CA), 
let me know; Jim enjoys correspondence  and can tell you the  mfr 
and model of the stepdown transformer he's using.

Q:  "3. Do you have an address  where one can order  one of these 
babies?"
A:  Although I'm not certain  this is the same subcontractor  who 
   mfd'd  the UNIXPC's power supplies, I have found this entry in 
   one of my various    buyer's guides:

        Power Systems, Inc.
        12 Tobey Road
        Bloomfield, CT  06002
        ph:  203/243-0357
        TWX: 710/425-8778

In case news has "expired" at  your site, repeating  the original 
info: 

The  3B1 power supply is  mfd by Power Systems, Inc. and is their 
model  PS 1610-1 (Convergent part number D-65-00056-1,  Rev. B).  

Its specs:
        90-130 VAC, 245 Watts, 58-63 Hz
        +5 VDC at 20 Amps
        +12 VDC at 5 Amps
        -12 VDC at 300 mA

The  7300 power supply is also  mfd by Power Systems,  Inc and is 
model  PS 1569 (Convergent  part number D-65-00042-00,  Rev. E).  

Its specs:
        90-130 VAC, 58-63 Hz
        +5 VDC at 20 Amps
        +12 VDC at 3.5 Amps
        -12 VDC at 100 mA

Thad Floryan [ thad at cup.portal.com (OR) 
..!sun!portal!cup.portal.com!thad ]

Many thanks to Thad and Lenny for the above info.

-- 
Julian Macassey, n6are  julian at bongo.info.com  {ucla-an!denwa!bongo!julian
N6ARE at K6IYK (Packet Radio) n6are.ampr.org [44.16.0.81] voice (213) 653-4495