Bitcoin Forum
December 15, 2018, 03:08:26 PM *
News: Latest Bitcoin Core release: 0.17.0 [Torrent].
 
   Home   Help Search Login Register More  
Pages: [1]
  Print  
Author Topic: Anyone know the Avalon 741 molex connector and how to repair it?  (Read 106 times)
subie
Newbie
*
Offline Offline

Activity: 58
Merit: 0


View Profile
March 19, 2018, 12:25:06 PM
 #1

Hello everyone,

One of the Avalon molex connector got burned by the PSU.

Does anybody know what is the model of the Avalon 741 molex connector? and how to repair/solder a new one into it?

https://dl.dropboxusercontent.com/s/sk3244bz3l12yr1/left_hashboard_burnt6pin2.JPG


Thank you!
PLAY NOW
Advertised sites are not endorsed by the Bitcoin Forum. They may be unsafe, untrustworthy, or illegal in your jurisdiction. Advertise here.
1544886506
Hero Member
*
Offline Offline

Posts: 1544886506

View Profile Personal Message (Offline)

Ignore
1544886506
Reply with quote  #2

1544886506
Report to moderator
HagssFIN
Legendary
*
Offline Offline

Activity: 1106
Merit: 1243


Electrical engineer (B.E.). Mining since 2014.


View Profile WWW
March 19, 2018, 12:54:49 PM
 #2

Uhh, that's badly burned.  Undecided

See my post here --> https://bitcointalk.org/index.php?topic=3121002.msg32670392#msg32670392

subie
Newbie
*
Offline Offline

Activity: 58
Merit: 0


View Profile
March 20, 2018, 07:51:45 PM
 #3

Thank you HagssFIN, I will reach out to lightfoot.
lightfoot
Legendary
*
Offline Offline

Activity: 1694
Merit: 1052


I fix broken miners. And make holes in teeth :-)


View Profile
March 20, 2018, 08:36:39 PM
 #4

Crunchy. I'd recommend sending it in for repair. The trick with these is you need to have preheat to warm the board enough to get the component off without damaging the vias. Doable, but requires some tools.

JHenry01
Newbie
*
Offline Offline

Activity: 4
Merit: 0


View Profile
March 25, 2018, 02:05:27 PM
 #5

lightfoot, is this a common problem with the HP common slot PSU's?  I had the same problem recently using Deepinthemines breakout boards with 750w PSU's
JHenry01
Newbie
*
Offline Offline

Activity: 4
Merit: 0


View Profile
March 25, 2018, 03:19:25 PM
 #6

Its MOLEX, LLC part number 0039301060

digikey has it: Digi-Key Part Number WM1353-ND

https://www.digikey.com/product-detail/en/molex-llc/0039301060/WM1353-ND/561080

I took apart my avalon 741 and removed the EBE5 pcb that has the molex connectors on it so I could work on it, the black plastic from the male connector had melted onto the female connector.  Put a hairdryer to it to soften the plastic a bit and was able to clean it out using needle nose pliers and a pick.  Anyway I am able to plug the PSU back in but I will be replacing this as soon as my order from digikey arrives.  

Tools:
Hakko 808 de-soldering station
Weller WES51 soldering station
Hobby creek helping hands holder
patience

I am switching out the HP common slot 750w with the 1200w's.  These pull 900w on 110v lines.  I was using the deepinthemines HP 1500W/1200W/750W DITM-W-12-75 plain breakout boards wired up with 16GA cable one 12V cable and one Ground cable per molex connector.

heres the damage:

https://imgur.com/a/rQjNM
Geronimoe
Newbie
*
Offline Offline

Activity: 20
Merit: 0


View Profile
March 25, 2018, 04:17:04 PM
 #7

JHenry01
Think your main problem is your cabling and not the PSU.
Looking at your pics you are using a single wire of 16awg for ground and supply to a single pin of the molex connector
The amps should be spread across all 6 pins of the molex connections with 6 x 16awg to stop it from overheating the wire.
JHenry01
Newbie
*
Offline Offline

Activity: 4
Merit: 0


View Profile
March 25, 2018, 04:33:10 PM
 #8

ok, starting to crimp some more cable right now.  I've got 12 psu's to rewire Embarrassed
philipma1957
Legendary
*
Offline Offline

Activity: 2310
Merit: 1425


Avalon 841 rocks


View Profile
March 25, 2018, 04:40:49 PM
 #9

Its MOLEX, LLC part number 0039301060

digikey has it: Digi-Key Part Number WM1353-ND

https://www.digikey.com/product-detail/en/molex-llc/0039301060/WM1353-ND/561080

I took apart my avalon 741 and removed the EBE5 pcb that has the molex connectors on it so I could work on it, the black plastic from the male connector had melted onto the female connector.  Put a hairdryer to it to soften the plastic a bit and was able to clean it out using needle nose pliers and a pick.  Anyway I am able to plug the PSU back in but I will be replacing this as soon as my order from digikey arrives.  

Tools:
Hakko 808 de-soldering station
Weller WES51 soldering station
Hobby creek helping hands holder
patience

I am switching out the HP common slot 750w with the 1200w's.  These pull 900w on 110v lines.  I was using the deepinthemines HP 1500W/1200W/750W DITM-W-12-75 plain breakout boards wired up with 16GA cable one 12V cable and one Ground cable per molex connector.

heres the damage:

https://imgur.com/a/rQjNM

Does anyone have one of these modules?  I could use one.


I mine alt coins with https://simplemining.net...
I see BTC as the super highway and alt coins as taxis and trucks needed to move transactions.
NotFuzzyWarm
Legendary
*
Offline Offline

Activity: 1652
Merit: 1141


Evil beware: We have waffles!


View Profile
March 26, 2018, 01:38:43 PM
 #10

Not to rub it in but... *why* on earth would a person wire these plugs using only 1 wire pair? Did they seriously think that it would work and all those other connections are just unneeded spares?

For bitcoin to succeed the community must police itself - Joshua Zipkin aka Joshua Alexander leaked AMT A1 miner skype chats
How a miner mfgr SHOULD operate: HaggsFIN trip to Canaan My info useful? Donations welcome! 1Fuzzyk398kDWVjuC5qPX5v6CjSkvbgAbd
-Support Sidehacks miner development. Donations to:   1BURGERAXHH6Yi6LRybRJK7ybEm5m5HwTr
philipma1957
Legendary
*
Offline Offline

Activity: 2310
Merit: 1425


Avalon 841 rocks


View Profile
March 26, 2018, 07:21:32 PM
 #11

Not to rub it in but... *why* on earth would a person wire these plugs using only 1 wire pair? Did they seriously think that it would work and all those other connections are just unneeded spares?

he had a bad day I guess

I mine alt coins with https://simplemining.net...
I see BTC as the super highway and alt coins as taxis and trucks needed to move transactions.
lightfoot
Legendary
*
Offline Offline

Activity: 1694
Merit: 1052


I fix broken miners. And make holes in teeth :-)


View Profile
March 27, 2018, 11:23:47 PM
 #12

lightfoot, is this a common problem with the HP common slot PSU's?  I had the same problem recently using Deepinthemines breakout boards with 750w PSU's
The root of the problem is either wires that are too small to the plug, or a power supply that sags under load. The sagging thing is interesting, if the voltage drops to 10v, the current has to go up to maintain the load. Since P=IE (mmmm, pie!) lower E=higher I. Which causes more heat, which increases the resistance of the pin which leads to more voltage dropped and the usual burning.

I use the Emerson supplies myself with 16 gauge wire plugs. No problem there. In terms of getting the plugs off I find that using some good old rosin/lead solder on the pins first (to allow with the ROHS) REALLY drops the melting point a nice bit and makes it easier. You can also get some chipquick. :-)

C
lightfoot
Legendary
*
Offline Offline

Activity: 1694
Merit: 1052


I fix broken miners. And make holes in teeth :-)


View Profile
March 27, 2018, 11:25:01 PM
 #13

Not to rub it in but... *why* on earth would a person wire these plugs using only 1 wire pair? Did they seriously think that it would work and all those other connections are just unneeded spares?

he had a bad day I guess
Heh. I remember someone who actually chained a second BFL single miner onto the second plug, and wondered why it toasted the first plug. Same engineering failure as the Kansas City walkway collapse.

(ie: oops)
lightfoot
Legendary
*
Offline Offline

Activity: 1694
Merit: 1052


I fix broken miners. And make holes in teeth :-)


View Profile
March 27, 2018, 11:31:23 PM
 #14

Not to rub it in but... *why* on earth would a person wire these plugs using only 1 wire pair? Did they seriously think that it would work and all those other connections are just unneeded spares?
To be more serious, I'm guessing he had all three plugged in. The reason one toasted is that heat thing: Remember as the pins get hotter the resistance goes up. Which means it drops more voltage which means more heat. It's a positive feedback loop, and why you see one pin incinerate, then the second, then the third. With multiple plugs one burns first then the second then the third.

C
Pages: [1]
  Print  
 
Jump to:  

Sponsored by , a Bitcoin-accepting VPN.
Powered by MySQL Powered by PHP Powered by SMF 1.1.19 | SMF © 2006-2009, Simple Machines Valid XHTML 1.0! Valid CSS!