SATA power connectors - where to get them ?

Just buy the right cable you need. The cost has to be cheaper than your time, much less the time to make sure that you got it wired right.

They are ubiquitous.

Do you try to make your own flashlight? No. You BUY one at the store.

SATAcables.com is one source.

I would if I could get exactly what I need.

I am designing enclosure for custom made RAID server for 40 SATA disks with hotswap capability and for that I need a cable with multiple connectors at exact lengths.

This means that I need to aseemble them myself.

WRT to making a mistake with wire positions, I'm not afraid of that. One would have to be drunk to make such simple mistake and not been able to see it until he actually connects the drive.

It shouldn't also be a problem to make a simple tester or use cheap old drive for testing.

Well, Molex makes the connectors, and there's a bunch of options. They also make cable assemblies.

It's not clear how you'd 'hotswap' but I'm thinking there's an adapter board and backplane involved, maybe the SATA cable part is just a shortie? So, maybe buying forty 'standard' subassemblies is less expensive than the crimp tooling to build your own.

Y adapters would make 2 short pigtails each, 99c free shipping eBay.

40 SATA drives? Wow.

How many different power supplies are you going to use for all of those SATA drives?

Would you REALLY want all 40 on the same power supply unit?

Would having 20 or 40 separate tiny power supply units be more reliable or less reliable than a situation where all 40 are on the same power supply??

Would you want a situation where all 40 go down at once, or one drive dying kills all 40?

Then again, how much trouble would

40 separate tiny power supplies present? ( Greater chances of failure? ) ( BUT they would each come with their own power pigtail!)

How many such units would you likely build? For one or two such units it might actually be cheaper to buy a bulk lot of pigtails and cut them shorter rather than buy the crimping tool.

Would it PAY to use 40 of these individual PS units they sell to use for external drive enclosures or would they create 40 times the failure rate?

That's 2.474 per power supply unit. $ 123.70 for 40 before shipping.

(You'd probably want to order some spares though)

Model Number:YH-3018 Input:100-240V/AC 50/60Hz,2A Output:12V--2A ,5V--2A

Not meant to endorse the vendor in any way...

Thanks, but this version doesn't allow me to string several connectors on one cable- it is meant for end of the cable.

I could improvise by using cable fragments between connectors, but I really don't trust crimping very much.

Still, it seems useable if I don't find anything better...

WRT to hotswap, SATA is AFAIK hardware-wise capable of it, it is just that it has no electronic for removal in insert detection. Otherwise, there should be no damage from drive insertion or removal under power.

So, my plan is to use userland application for drive rescan after drive swap...

WRT to enclosures, I think I can manage without them.

Yes. Power consumption of a single drive is around 7W, which means that 400-500W should be enough for 40 drives.

Besides, I was talking about enclosure, not actual capabilities of the system. I find it usefull to have some spare room in enclosure, since space is not at premium.

WRT to PSU- I am toying with the idea of designing one of my own. After trying many off-the-shelf units i find experience quite a dissapontment.

Also, I have made local 300VDC installation in my workshop, which is backed by battery. Basically, I have 20 x 12V/60Ah Pb batteries in series which makes 240-300V DC, depending on state of batteries. I use rectified 3-phase AC 220V, which gives me around 300V DC.

So, practically all my equipment ( computers, monitors, many tools, illumination etc) already work on DC. WRT to computer PSU units, I think I could further optimize them for such conditions and to improve their efficiency further.

You do NOT need 18 gauge wire. You need to branch up at the supply, not at the feeds to each drive.

No, putting a string of five drive supply lines on one cable is not a good idea.

You should also use at least a dual supply redundant system as well, and perhaps even a supply (or two) for each pair of drives.

Repairing one failed drive or continuing to feed data requests with one drive down in an array can be done. Placing them all on the same supply means that a supply failure brings down the whole system. A very poor design.

Discreet supplies would insure continued RAID operation with as many as two failures (I think), and rebuild/restore/update them when they came back up.

Why are you going to use 40 drives rather than fewer larger ones?

Could you put some pictures of your power conversions for computers and monitors on photobucket or similar?

I'd like to see your 300v battery and how you converted computer and monitor power supplies to run on DC.

Are you really in the LJUBLJANA Slovenia area, "Brane2"?

How is it that a guy capable of such power conversions can't locate these connectors?

Are you sure you want to set it up so that if only one of the 40 drives fails short, that the power supply and all other drives are shut down?

Again, why 40 drives and not fewer larger drives?

A true switching power supply will "come up" just fine with a DC input, provided it is of the right voltage (above 'low line').

Greegor was thinking very hard :

We might get to see the blue flashes and smoke if anything goes wrong with that 300volt supply. To the OP What is the point of all this diversion from standard tried and proved methods? >:|

--
John G

He is an utter retard.

Dual dongles on each would be better, cheaper, and more reliable.

,

I don't understand this. Connector's datasheet says it is needs AWG18. If I use it for whole group, then wire resistance gets unpleasantly high. If I "branch up at the supply" then I get whole mess of many separate power supply cables from PSU to the drives. Intention was to use multiple wire high current wire clamps on PSU side into which i could insert stripped end of all wires and then tighten them up with screwdrives or something. Power to drives would go through several thicker cables, one for each group, each cable of the exactly needed length, with connectors at the exactly needed places.

I could, but in practice I don't really need them for my application. DC is by its nature trivially filtered ( essentially one BIG cap will do the job), so voltage spikes of any practical energy are essentially nonexistent. It works very stable even without batteries, since short power outages that otherwise lock the system will rarely happen on all thre phases simultaneously. Furthermore, with three phases rectified input voltage never drops under Vmax/2 even without extra cap, so net power caps in PSU units have much easier jobs.

PSU failure is no big deal for my application, as longf as I have spare unit at hand. Relatively speaking, biggest percentage of all access is for reading, and eventual failed write can be repeated most of the time.

Under such conditions, two PSUs would be nice, but even one is good enogh, with other one as a cold spare on the shelf...

ne

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Depends on the application. But even so, I don't see the connection. If I have all drives in one RAID group and they are powered by two PSUs - one for each half of the group, then ANY PSU failure would stop my RAID.

Using special PSUs that can work in parallel and where EACH can cover power requirements of the whle system would be a different story, but for my needs unnecessarily complex and expensive.

as

Don' care for my app. Also, tolerance of two failed drives comes at steep price. Calculating Q-syndrome for RAID-6 is not trivial for SW RAID, while simple XOR is used for RAID-5.

This is the reason that I use RAID-5 + hotspare + coldspare + periodical backup of files in the "I_WOULD_DIE_WITHOUT" map to local hard disk on the shelf etc.

Why ? It works FLAWLESSLY for more than 4 years the teh moment.

Even more, before the conversion, I had seasonal PSU failures. Each spring we get showered with lightnings well above year average and this was usually the time when PSU in some of computers had died. After conversion, all PSU deaths were strictly related to their quality and age, not power grid events.

How much would you pay for the unit that has all the qualities of profi On-Line UPS units, routinely supply you with 10 kW of power if needed and give give you at least 20kWh worth of energy without much effort ?

1. I am not going to use 40 drives, but make casing with 40 drive bays. What is the difference ? Empty bays that can be well used. For example, for cold spares. Or for occasionaly plugging in a backup drive or three. Or for data migration from old raid to the new one etc etc.
2. So one can use drives with best space/price ratio or performance/ price etc.
3. Let say that I want RAID-5 with 32 2TB drives in RAID, one hot spare and one cold spare. This means 60-ish TiB RAID in 34 bays with 6 bays free. What is your alternative - 3TB drives ? That would mean few drives less but much higher price in the end...

Bane2: What kind of work are you doing that needs this much hard disk space, RAID-5 with 64 Terabytes, and are you really in the LJUBLJANA Slovenia area?

Is this a cryptography project on a government budget or how are you paying for all of this?

Please post links to photos of your PS conversions.

Someone has to have backup of the Internet ;o)))

Disks are dirt cheap. 2TB for =8060+. At the moment I have 15 TiB RAID-5 aray, made from 9 x 2TB + 2TB as hotspare.

But it would be fine to have more. Copies of our film materials, projects, ISOs of ur DVD disks etc etc.

I find it ubercool to have one massive server and to work on relatively lean workstations with small or without any HDD. That way I always know exactly where needed data is, regardless of which machine am I working ATM.

For me, access speed of hard disk is irrelevant for the most part. Any data that is not available locally on my server is for me almost useless. Disks are nowadays cheap, they don't burn much juice and even cheap ones can be used to build RAID arrays with dizzying transfer speeds on the cheap...

maybe later, when I finalize it an pollish it into something sellable, write a decent article etc.

Brane2: Did you used to use the name Green Xenon? You're starting to resemble him. He has Aspergers. What's your excuse?

Slovenia?

Never.

I'm an asshole.

Nice village.

You ain't real bright, boy.