CMD HD power supply replacement

[dr.v]

Hi guys.  I have the stock (knock on wood, still working) power supply for my CMD HD.  The older, switchable stock PS.  I want to have a backup PS.  The stock PS I have is rated 12V @ 1A and 5V @ 4.5A.  One of the replacements I'm looking at does 12V @ 1A and 5V @ 2A.  I remember reading somewhere on the internet (I have since searched and couldn't find the post) that the 5V line was for the drive mechanism itself and the 12V line ran the contoller (more or less).  Hence the current drawn at 5V will depend on the particular drive mechanism used.  I checked out my quantum mech and my seagate mech and neither specify a maximum drawn current.

Is 5V @ 2A sufficient or am I inviting trouble?

Tom

[RobertB]

The stock PS I have is rated 12V @ 1A and 5V @ 4.5A.

Sounds like the P.S. that came with one of CMD HD's.  In reality, CMD just provided a delabeled A500 power supply with a round connector for the HD.

Is 5V @ 2A sufficient or am I inviting trouble?

Without going through the trouble of digging out the low-powered CMD p.s. from my other HD, at the same website at http://come.to/cmd64  it tells that the (original?) requirement is 5V @ 2.2A.

          Truly,
          Robert Bernardo
          Fresno Commodore User Group
          http://videocam.net.au/fcug
          The Other Group of Amigoids
          http://www.calweb.com/~rabel1/
          Southern California Commodore & Amiga Network
          http://www.sccaners.org

[dr.v]

Good call, Robert.  Thanks.  Well if 5V @ 2A is near sufficient, I guess brand new CMD HD power supplies are easy and inexpensive to obtain!  That's great news.

[RobertB]

...I guess brand new CMD HD power supplies are easy and inexpensive to obtain!

If you don't want to mod an A500 p.s. for the CMD HD, then you can take an AT p.s., wire in the appropriate cable with round connector, and grab the power from that p.s. for the HD.

          Plenty of power there,
          Robert Bernardo
          Fresno Commodore User Group
          http://videocam.net.au/fcug
          The Other Group of Amigoids
          http://www.calweb.com/~rabel1/
          Southern California Commodore & Amiga Network
          http://www.sccaners.org

[dr.v]

Or I could drop $15 and buy a brand new one from ebay.  My only concern is/was it supplies 5V @ 2A.  Not 2.2A.  But I think it will suffice.  Even if I modified an A500 PS - I am still modifying an aging power supply.  The AT PS is something I may do at some point.  Not just for the hard drive, but to run several pieces of equipment from a single power source.
 

[maraud]

Or I could drop $15 and buy a brand new one from ebay.  My only concern is/was it supplies 5V @ 2A.  Not 2.2A.  But I think it will suffice.  Even if I modified an A500 PS - I am still modifying an aging power supply.  The AT PS is something I may do at some point.  Not just for the hard drive, but to run several pieces of equipment from a single power source.

It should be enough.  I ran mine 100% stable for a year on a 1581 PSU.  However, I replace the HDD with a solid state unit, so that reduced the power needed.  You'll just need to find a drive with a max draw of 10W to keep it at 2 AMP.