1200A 12V power supply

[MattiFin]

I think this should qualify for Danger Zone: Bought 6x HP Bladesystem 7000 12V 2400W power supplies for next to nothing (about 7usd/pcs)
Connected in parallel I should have compact 12V 1200A power supply.

Now I'll just have to find bunch of those C19 power cords. Looks like I'm going to end up paying more for the power cords than the power supplies.

 

[JBertok]

If those are the same ones I am thinking of, I am pretty sure they need high voltage input. The last C7000 chassis I saw running was on a 208V UPS and PDU. They will run on 240V too.

 

[DIYrich]

If you are connecting in parallel, you may pay even more for handling the 1,200a output.

 

[Chuntzu]

I think this should qualify for Danger Zone: Bought 6x HP Bladesystem 7000 12V 2400W power supplies for next to nothing (about 7usd/pcs)
Connected in parallel I should have compact 12V 1200A power supply.

Now I'll just have to find bunch of those C19 power cords. Looks like I'm going to end up paying more for the power cords than the power supplies.

I have done this with 12xhp server power supplies, I have it set up for 14.5v so 1200amp continuous and 1800ish peak for a few seconds!

 

[Symbioquine]

Probably worth mentioning (at least for other folks that find this topic), power supplies like the ones for computers usually aren't designed for supplying constant current (CC). In other words they will try and hold their output voltage stable at all costs until you try and draw too much power at which point they (should) shut off to protect themselves and the load.

Not sure what OP is trying to use this power supply for, but it probably isn't suitable for general purpose battery charging. (Though I suppose it might work for lead acid battery charging which is usually pretty self-limiting in terms of charge rate.)

 

[wpns]

Connected in parallel I should have compact 12V 1200A power supply.

Wow! But also: Why?

 

[MattiFin]

Wow! But also: Why?

Replace batteries when bench testing 12v inverters, use as auxilary power supply with car ecu updates or something like that.
Heck, at that price and current capability I might even use them as a car booster starter.

Probably worth mentioning (at least for other folks that find this topic), power supplies like the ones for computers usually aren't designed for supplying constant current (CC). In other words they will try and hold their output voltage stable at all costs until you try and draw too much power at which point they (should) shut off to protect themselves and the load.

Not sure what OP is trying to use this power supply for, but it probably isn't suitable for general purpose battery charging. (Though I suppose it might work for lead acid battery charging which is usually pretty self-limiting in terms of charge rate.)

These are server power supplies designed for redundant operation.
One chassis can have up to 6 of these parallel and they manage current/load sharing "somehow" between the invindual power supply units. While they are certainly not battery chargers there is a slightly better change that they have active current limitation instead of just shutting down.

 

[Chuntzu]

Wow! But also: Why?

Very good question! I had most of the power supplies laying around from server builds that I have done for people over the last 10 years or so, and they weren’t doing anything. It powers some 12v amplifiers I have for car audio that I was into when I was younger. They have cosmetic stractches and the like so not going to fetch top dollar selling them. It makes for a very over powered garage stereo setup. there are a bunch of people on rc car forums that sorted out a lot of these power supplies for there battery chargers like the x8 and what not. But the cb radio guys figured out the parallel pin and how to adjust the crowbar and voltage settings to make these useful for there needs. I have been working on some high c-rate battery testing with scib lto cells but it’s not cheap to find 500amp capable power supplies. When I actually get the test rig set up with the electronic loads and data acquisition hardware in place to safely test charge and discharge of 12-15v 500 amps I will post it up but for now it was super cheap to build and works like a dream! Sorry for the ramble trying to speed type while working on something!

 

[Chuntzu]

Replace batteries when bench testing 12v inverters, use as auxilary power supply with car ecu updates or something like that.
Heck, at that price and current capability I might even use them as a car booster starter.


These are server power supplies designed for redundant operation.
One chassis can have up to 6 of these parallel and they manage current/load sharing "somehow" between the invindual power supply units. While they are certainly not battery chargers there is a slightly better change that they have active current limitation instead of just shutting down.

Exactally bench flashing ecus and I have no doubt this could handle starting a car. There are guys running 20-30 of the 1200-1400 watt in parallel for large cab radio setups that have showed 2800-3000 amps at 15-16v

 

[wpns]

large cab radio

CB radio? 48KW input? Yowza!

 

[Chuntzu]

CB radio? 48KW input? Yowza!

Right!!! But I can understand the want for something way over built/over the top. Sometimes it’s fun to push the boundaries and see what things can do. Not shown in the photos are the fuses, breakers, etc so that I don’t hurt myself or others while having some fun.

 

[Sennen]

They're just trying to turn the "Tickle Me Elmo" into an "Inhale Me Elmo"

 

[Chuntzu]

They're just trying to turn the "Tickle Me Elmo" into an "Inhale Me Elmo"

I’m going to be honest, I have no idea what this means.

 

[Supervstech]

I’m going to be honest, I have no idea what this means.

 

[Sennen]

I’m going to be honest, I have no idea what this means.

Someone ran an excessive amount of voltage through toys out of boredom...

 

[Chuntzu]

Someone ran an excessive amount of voltage through toys out of boredom...

This was awesome! Very rarely do I find myself actually laughing out loud to something! This one got me, and the smoke at the end was priceless! Thank you for that!

 

[efficientPV]

I bought a number of those server power supplies. I haven't seen one that will do 14.5V. I made them slightly adjustable. From what I remember they go into over voltage shutdown. Although mine were PFC, the chip didn't mind DC on the input.

 

[Chuntzu]

I bought a number of those server power supplies. I haven't seen one that will do 14.5V. I made them slightly adjustable. From what I remember they go into over voltage shutdown. Although mine were PFC, the chip didn't mind DC on the input.

A lot of them don’t have documentation adjusting the voltage up or down. The ones I picked up, have two locations you add a resistor and it allows you to adjust the voltage (higher) in my case and adjust the crowbar (this was the term used by the folks who figured it out) which gives you some adjustability on when too high of a load will kick out the power supply. Like the over voltage protection.

 

[MattiFin]

Modifiying the output voltage wasn't the easiest one. I traced the 12v feedback to the control board but there is no easy way to cut the trace at any point. Found also instructions in russian: https://www.drive2.ru/b/579148509551264539/

There seem to be still active OVP circuit somewhere on the PSU even I thought that the OVP would be from the same trace as control voltage.
Adjustment range goes up to 14.2v so I don't feel necessary to poke around with the OVP any further.

For modification you need either serious big-ass soldering iron to remove the coil or good desoldering station and a bit of skill to remove the control board.
I opted to remove the control board, method shown on link above would need 300W lead roof soldering iron.
Control board is also a bugger to remove, some of the pins connect to heavy ground pours that suck all the heat from your iron.