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Electronics => Repair => Topic started by: najrao on December 07, 2017, 01:47:06 pm

Title: IBM server power unit now bricked
Post by: najrao on December 07, 2017, 01:47:06 pm
I attach three pictures of the animal I picked up in apparently perfect serviceable condition. Though I am moderately good at deciphering dc power supplies, this very high power unit has left me baffled for a long time. If I can get it going, I can put it to good use, especially the 3.3/5V 150A output. There is no data forthcoming from IBM websites.
I can feed it at 350V dc from external PFC unit.
Obviously, no connectors are available, and I have to devise other ways, but that has not deterred me in the past.
I did do some sort of pinout identification, but the problem is finding what will 'enable' the output.
I would be grateful for any leads.
Title: Re: IBM server power unit now bricked
Post by: coromonadalix on December 07, 2017, 06:04:39 pm
there is a forum for server powersupplies, dont recall the name,  you can find bunch of psu pinouts there, and get some help

Normally you should have a 5vdc standby supply (constant voltage)

Sometime i did find the startup pin by adding a 4.7k - 10 k resistor in series with the 5vdc standy supply, and the psu should/would start, unless there is a voltage to ground startup pin ???
Title: Re: IBM server power unit now bricked
Post by: Nusa on December 07, 2017, 06:30:02 pm
there is a forum for server powersupplies, dont recall the name,  you can find bunch of psu pinouts there, and get some help

Normally you should have a 5vdc standby supply (constant voltage)

Sometime i did find the startup pin by adding a 4.7k - 10 k resistor in series with the 5vdc standy supply, and the psu should/would start, unless there is a voltage to ground startup pin ???

You're probably thinking of the rcgroups.com forum, that has reported on a lot of successful server supply pinouts and conversions usually for battery charging purposes. I've got some on my own shelves: 12V 40A DC supplies that cost me a whole $5 each to buy and convert.

It's not going to help in this case as this isn't the kind of supply that's useful to the RC industry. It's a DC-DC converter, expecting 350V DC as input. A supply voltage that makes sense in data centers, but rarely out in the real world.

The only people that are going to know much about this are the people that actually used them. And those people generally had the correct cables and backplane slots.
Title: Re: IBM server power unit now bricked
Post by: najrao on December 08, 2017, 03:44:15 am
RC groups had no answer.
Frankly, I have not gone enough deep into it yet, and will try to locate any Vsb and start up pins. There are three jacks, two at the front, with 32 pins in all. The main power jack seems to be all outputs.
I attach a picture of the innards, if that helps.
Title: Re: IBM server power unit now bricked
Post by: Bashstreet on December 08, 2017, 07:43:48 pm
Do you even know for sure there is pin out for PS_ON .

Why have you not tested the pins for power ?

As coromonadalix said there must be open line for 5v or or similar to offer the PS_ON