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Other => CPU/GPU Bitcoin mining hardware => Topic started by: aznatama on September 29, 2013, 08:29:59 PM



Title: can I use Ebay USB hub w/ 40a power supply?
Post by: aznatama on September 29, 2013, 08:29:59 PM
I was wondering, since the main issue seems to be insufficient power...

I have a 10-port ebay USB hub that came with a 5v 2a adapter.  However, after a few minutes of mining on my Erupters (3 installed), one will stop working, and overall, there's a high HW error rate.  two will work just fine though.  So I'm thinking that the main issue is power. 

Would it work if I wired these to a 5v 40a regulated power supply?


Title: Re: can I use Ebay USB hub w/ 40a power supply?
Post by: Photon939 on September 29, 2013, 08:34:14 PM
I was wondering, since the main issue seems to be insufficient power...

I have a 10-port ebay USB hub that came with a 5v 2a adapter.  However, after a few minutes of mining on my Erupters (3 installed), one will stop working, and overall, there's a high HW error rate.  two will work just fine though.  So I'm thinking that the main issue is power. 

Would it work if I wired these to a 5v 40a regulated power supply?


Most likely yes, but be careful with the cheaper hubs, they tend to be undersized for significant power draw. I am currently using a cheap hub with five BF1 usb miners but I had to solder the power wires directly to the pcb because the barrel jack was tiny and would've melted at  3+ amps of current.

I run 10 port hubs wired to an ATX psu's 5v rail that is also powering some BFL gear on the 12v rail. Keeps things tidy


Title: Re: can I use Ebay USB hub w/ 40a power supply?
Post by: aznatama on September 29, 2013, 08:56:52 PM
Yeah, I already looked at the connections.  They look alright, but I'll keep an eye on them and monitor tems as well to see how it works out.  Thanks.

I may wire the power supply to my Rosewill 10-port hubs as well, since it only allows 8 miners w/ stock supply.  This should clean up the wires.

Lastly, anyone know where to get barrel plug leads? not ones where I have to solder all the wires, but complete leads?  I would prefer not butchering the stock adapters, but I'll do that if I have to.


Title: Re: can I use Ebay USB hub w/ 40a power supply?
Post by: mogrith on September 29, 2013, 09:02:03 PM
not sure what size you need.
try http://www.digikey.com/product-search/en/cable-assemblies/barrel-power/1573698 (http://www.digikey.com/product-search/en/cable-assemblies/barrel-power/1573698)


Title: Re: can I use Ebay USB hub w/ 40a power supply?
Post by: aurel57 on September 29, 2013, 09:58:07 PM
I had two different 40 amp PSU that I tried and both failed. I do have two 20 amp PSU that are running 56 miners. I also started a blog with the links to the parts I bought. http://aurel57.blog.com/    http://aurel57.blog.com/files/2013/09/usb-hub-pictures-007-1024x769.jpg http://aurel57.blog.com/files/2013/09/asic-USB-miners.jpg


Title: Re: can I use Ebay USB hub w/ 40a power supply?
Post by: ssateneth on September 29, 2013, 10:21:22 PM
I tried those cheap chinese hubs. they're terrible, both with packed ac adapter, and separate 5v power. they blow. I had the ebay seller refund me after I sent them back.

If I buy a 10 port hub, I expect all 10 ports to work. No excuses.


Title: Re: can I use Ebay USB hub w/ 40a power supply?
Post by: aznatama on September 29, 2013, 11:16:10 PM
Aurel57,

Is there a reason you only ran 6-7 miners per hub?


Title: Re: can I use Ebay USB hub w/ 40a power supply?
Post by: aurel57 on September 29, 2013, 11:20:59 PM
Aurel57,

Is there a reason you only ran 6-7 miners per hub?
I only did because I had extra hubs and wanted to balance the load. I have had all 10 ports filled before but have been doing different combinations and checking voltage drop across the hubs. I have more USB miners coming in the next day or so and will start up another PSU and fill some of the hubs up as I get 70 miners hashing.


Title: Re: can I use Ebay USB hub w/ 40a power supply?
Post by: aurel57 on September 29, 2013, 11:24:03 PM
I tried those cheap chinese hubs. they're terrible, both with packed ac adapter, and separate 5v power. they blow. I had the ebay seller refund me after I sent them back.

If I buy a 10 port hub, I expect all 10 ports to work. No excuses.
There have been reports of even the Anker hubs having problems. But at $60+ per hub it starts to add up if a person wants to run 70-100 miners


Title: Re: can I use Ebay USB hub w/ 40a power supply?
Post by: aznatama on September 29, 2013, 11:37:25 PM
That's good to hear.  I plan to run 9 per hub, and I have the exact same hubs.  the port at the end is a little weird, and I may or may not fill that one.

Now to get some power cord leads...


Title: Re: can I use Ebay USB hub w/ 40a power supply?
Post by: Eternity on October 08, 2013, 03:03:17 PM
Buy hubs that are sold on amazon you will find some really good ones


Title: Re: can I use Ebay USB hub w/ 40a power supply?
Post by: surebet on October 08, 2013, 10:59:23 PM
Subscribing for future fire damage pictures.


Title: Re: can I use Ebay USB hub w/ 40a power supply?
Post by: aurel57 on October 09, 2013, 12:59:35 AM
Subscribing for future fire damage pictures.
No fires here.. And I added another 20a PSU which now have 70 miners total running. https://fbcdn-sphotos-g-a.akamaihd.net/hphotos-ak-ash3/1382810_10153322683680085_469328933_n.jpg


Title: Re: can I use Ebay USB hub w/ 40a power supply?
Post by: surebet on October 09, 2013, 01:30:27 AM
This was 7A run through a 2A hub:

https://i.imgur.com/s0SQ6XD.png
https://i.imgur.com/cO2FTkg.png
https://i.imgur.com/bITg6ke.jpg
https://i.imgur.com/lFv4pp9.png

40 amps. Yeah, go for it.


Title: Re: can I use Ebay USB hub w/ 40a power supply?
Post by: ElitePork on October 09, 2013, 01:45:43 AM
This really depends on how much Amp the hub is drawing. My hubs runs 8 BEs, (4OC + 4 stock) perfectly for days. It's a PSU of 5V 60A. It appears that it can't draw more than 10Amp for that hub and if you do, it will melt the power plug...


Title: Re: can I use Ebay USB hub w/ 40a power supply?
Post by: surebet on October 09, 2013, 02:42:58 AM
It's not just the plug you need to worry about, but it is a concern. Any other wiring in there like from the board to the PCB or the PCB itself might just decide to say fuck it and burn.

http://www.powerstream.com/Wire_Size.htm



Title: Re: can I use Ebay USB hub w/ 40a power supply?
Post by: h@shKraker on October 10, 2013, 03:47:47 PM
It is ABSOLUTELY TRUE .... you *CAN* catch a USB hub on FIRE if you have devices on it that pull enough current (ask me how I know :-D ).  The way I figure out when I'm getting close to the top end of allowd current in a USB hub device is I pull the plastic shroud off the 10-port strip hub and plug in just the hub PCB.  I then plug in my USB devices (block Erupters in this case) and with a dual latex gloved hand hold onto the USB PCB (Because 5 VDC@ 40AMPS will kill you graveyard dead if it passes across your heart).  I then power things up and if the USB hub PCB gets warm in my dual latex gloved hand I'm at a reasonable limit.  If the hub PCB gets hot in my dual latex gloved hand I pull the power plug IMMEDIATELY on the Hub and remove one USB stick and let the USB PCB cool to room temp.  Lather-Rinse-Repeat until you are holding a USB PCB that is only warm to the touch while running.  If you avoid this test you'll have a "fire ready / Fire making" USB hub PCB in a plastic enclosure (AKA surrounded by an accelerant) like the one in the pictures above  :o .


Title: Re: can I use Ebay USB hub w/ 40a power supply?
Post by: aurel57 on October 11, 2013, 09:43:49 AM
This really depends on how much Amp the hub is drawing. My hubs runs 8 BEs, (4OC + 4 stock) perfectly for days. It's a PSU of 5V 60A. It appears that it can't draw more than 10Amp for that hub and if you do, it will melt the power plug...
Pork of coarse you are right. It does not matter how many amps you have at the plug from the PSU unless its to low. What matters at that point is how many amps the hub is drawing. Then the only next thing is how well the connection is on the barrel plug, if the connection is not a good fit, they can heat up or if the amps are over the rated amount for the barrel plugs and/or circuit board. ( I am not sure what the max amps are for this hub but 10 amps may be well beyond the max?)


Title: Re: can I use Ebay USB hub w/ 40a power supply?
Post by: RaTTuS on October 11, 2013, 10:20:49 AM
it may also be worth "cutting the red wire" from the USB connector to the PC, this will stop power [+5V] being transmitted back to the PC on cheep hubs

Don't Daisy chain the hubs and power - power each separately


Title: Re: can I use Ebay USB hub w/ 40a power supply?
Post by: easynote on October 11, 2013, 03:51:51 PM
This china hubs is a fake... Poor material :D



Title: Re: can I use Ebay USB hub w/ 40a power supply?
Post by: mb300sd on October 11, 2013, 03:57:14 PM
I cut the power cord on a cheap hub and wired it into the host PC's 5V line, been running for 4 months now.


Title: Re: can I use Ebay USB hub w/ 40a power supply?
Post by: Zeek_W on October 12, 2013, 04:49:00 AM
Barrel connectors are NOT your friend.


Title: Re: can I use Ebay USB hub w/ 40a power supply?
Post by: terrapinflyer on October 14, 2013, 02:35:21 AM
So this is something I was thinking about today while I was looking at all the psu's plugged in to my power strips. Im considering this as a solution to that ugly mess of wires that my gf hates. I have all D-Link 7 port hubs that I would like to chain into one psu cord. Im guessing this http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=181143570443&fromMakeTrack=true&ssPageName=VIP:watchlink:top:en (http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=181143570443&fromMakeTrack=true&ssPageName=VIP:watchlink:top:en) should do the trick.


Title: Re: can I use Ebay USB hub w/ 40a power supply?
Post by: aurel57 on October 14, 2013, 08:33:13 AM
So this is something I was thinking about today while I was looking at all the psu's plugged in to my power strips. Im considering this as a solution to that ugly mess of wires that my gf hates. I have all D-Link 7 port hubs that I would like to chain into one psu cord. Im guessing this http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=181143570443&fromMakeTrack=true&ssPageName=VIP:watchlink:top:en should do the trick.
How many hubs are you going to run? I am using 3 of these PSU and running 70 USB miners https://fbcdn-sphotos-g-a.akamaihd.net/hphotos-ak-ash3/1382810_10153322683680085_469328933_n.jpg


Title: Re: can I use Ebay USB hub w/ 40a power supply?
Post by: terrapinflyer on October 14, 2013, 06:12:16 PM
I currently have around 60 miners so Ill probably do 3 as well. I was going to start with one and see how that go's Like I said Im really trying to clean up all the cords.