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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: Lo on February 07, 2003, 04:41:42 PM

Title: 2 Pwr Supplies in 1 box?
Post by: Lo on February 07, 2003, 04:41:42 PM
Voltage/connector issues aside, does anyone see any problems with this?

My meager 185 watt PS needs help if I want to have 3 HD's and 3 Disc drives in my HP 900A box, so I thought to use my old dead PB 166MMX pwr supply to power half of the drives?  Yes, it would fit ok.

Are there like, grounding issues? Or is 185W enuff?  Thanks for input
Title: Re: 2 Pwr Supplies in 1 box?
Post by: Karlos on February 07, 2003, 04:50:01 PM
Surely buying a much beefier replacement would be better?
Title: Re: 2 Pwr Supplies in 1 box?
Post by: Lo on February 07, 2003, 05:08:23 PM
Spending more bucks is always better, but hey, we are Amigans!  heh
Title: Re: 2 Pwr Supplies in 1 box?
Post by: blobrana on February 07, 2003, 05:39:15 PM
I`v e been tempted in the past to bolt on another power supply to the outside (at the back)...240 +

So apart from the extra noise, uglyness and potential death ( due to exposed wires) i see no reason why not to go ahead.
Title: Re: 2 Pwr Supplies in 1 box?
Post by: Wol on February 07, 2003, 06:34:11 PM
Hi,

Connect a GROUND WIRE ONLY !!! between
each power supply (0v), This will make sure
that each supply has the same GROUND reference.

DO NOT CONNECT ANYTHING ELSE !!!
OR IT WILL BE BOOM BOOM TIME..
 
Title: Re: 2 Pwr Supplies in 1 box?
Post by: Castellen on February 07, 2003, 07:55:32 PM
Should work fine, so long as the ground connections are common between power supplies.
Which they will be, the IDE/SCSI cables contain a number of ground connections which will do this for you automatically.

Using two power supplies in parallel will not cause them to blow up, the only thing that's going to happen is that if the output voltages are not equally ballanced between the two supplies, one supply is going to work harder than the other one.
Title: Re: 2 Pwr Supplies in 1 box?
Post by: Lo on February 07, 2003, 08:52:55 PM
ok, so ground the Black wires, right? no problem, here goes, I..*8~#zzt
Title: Re: 2 Pwr Supplies in 1 box?
Post by: iamaboringperson on February 07, 2003, 08:59:42 PM
Quote

Karlos wrote:
Surely buying a much beefier replacement would be better?

i agree!  :-D
its funny how some people think though, isnt it?
 :-o  :-o
Title: Re: 2 Pwr Supplies in 1 box?
Post by: Paul_Gadd on February 07, 2003, 09:22:52 PM
While power supplies at 300watt are so cheap is it really necessary to mess around using two when a new 300watt psu can be bought for around 8 quid.
Title: Re: 2 Pwr Supplies in 1 box?
Post by: iamaboringperson on February 07, 2003, 09:32:55 PM
or thirty bucks!
Title: Re: 2 Pwr Supplies in 1 box?
Post by: on February 07, 2003, 10:16:46 PM
My towerised a3000 works this way.

The original a3000 psu + an AT one.
Title: Re: 2 Pwr Supplies in 1 box?
Post by: iamaboringperson on February 07, 2003, 10:30:01 PM
Quote

keltia wrote:
My towerised a3000 works this way.

The original a3000 psu + anAT one.

ok, thats fair enough, since the A3000 uses its own custom PSU...  :-)
but unless you want a redundant power supply setup, 2 psu's is a dumb idea!
 :-)
Title: Re: 2 Pwr Supplies in 1 box?
Post by: lempkee on February 08, 2003, 01:15:33 AM
i have bad experience with this...

my mediator required me to use a AT psu ;( and since my amiga is powreed by ATX meant that i had to use 2 psu's ,
it resulted in that the fans on the weaker psu died, and almost killed my hdd's + keyboard adaptor (the AtX OnE) ,

on the ATX i had keyboard connector , 3 hdd's and cd + cdrw

on the AT i had mediator + the diskdrive etc...

but i forgot to mix the 2 grounds, so as i said....wasnt a good pleasure, but it seems to be OK now (when i am back on 1 psu)
i didnt fry more than 2 psu's (ATX ones) , 1 went first and i belived it was old and bad so i just got another one....and same happened again (after a 2+ month period)

hope this helps out, anyway i invested in a 400watt one...to supply all, and ofcourse its an AT one since my mediator is AT ...AAAAAAAAAAAAARGH...
(had to replace my rbm towerhawk adapter also with an elbox one... (keyboard ad.)

good luck
Title: Re: 2 Pwr Supplies in 1 box?
Post by: Quixote on February 08, 2003, 07:28:53 AM
Castellen cautioned:
Quote
Should work fine, so long as the ground connections are common between power supplies.  Which they will be, the IDE/SCSI cables contain a number of ground connections which will do this for you automatically.
;-) I take it that this is why my A3000's four external SCSI devices, each on its own power supply, have no troubles.
Title: Re: 2 Pwr Supplies in 1 box?
Post by: Castellen on February 08, 2003, 09:28:35 AM
Exactly right.
Using a 2nd power supply inside the computer case to power hard drives, CDrom, etc is no different to external SCSI devices and the like having their own seperate power supplies.

I can't say it's the tidiest way to do something, but there's no reason why it wouldn't work.