Most commonly available clamp ammeter do not allow you to measure DC using the clamp.

There's no Kill-A-Watt but there's definitely knockoffs available for 220/240V receptacles.

I would have expected a greater variance on the 5s hashrate than what yours appear to be showing.  On a sample of 10 units, I see 5s hashrates vary anywhere from <1TH up to over 3TH and sometimes even 6TH.

Gotcha.. what's your take on Ghash? 

Eclipse and Ghash haven't hit a "lucky streak" since October. 

Take a look at Organofcorti's mining pool stats. 

http://organofcorti.blogspot.com/2015/03/march-29th-2015-mining-pool-statistics_30.html

Ghash has been quite "unlucky" since October 2014.  Take a look at the stats for all of the other pools OoC creates.  Eclipse (BFL) and Ghash have both been strangely "unlucky".  The numbers don't lie. I used to mine on Ghash until the numbers started looking "funny". The stats, along with the ghash double spend fiasco have pretty much taken this pool off my list.

http://4.bp.blogspot.com/-C5ZNIUeeqpk/VPw6AAZgbJI/AAAAAAAABkk/1va1tLRLtyg/s1600/2a_profitPlot_2015-03-08.png

Can you SSH into it?

At 55CFM I don't think that fan moves anywhere near enough air to call it a replacement for the existing S4 fans.  Think you need something in the vicinity of 300 CFM.  And at $30USD I'd think you could do better by going with a Delta.  JMHO.

You lost me at "monarch"

I haven't mined on nicehash but I believe it's one of those altcoin hopping proxy pool, isn't it?  Altcoin blocks are much easier to find than btc blocks. Too bad those weren't all btc blocks. I'm guessing you've found quite a bit of practically worthless altcoin blocks. 

What is the single board running off the corsair pulling at the wall?  Wondering if I can run 2 overclocked boards off a single 750W server psu.

Can anyone please state which email provider they've gotten to work with this other than Verizon?

I've used:

• Gmail
• Comcast
• Wowway
• Yahoo
• AT&T

All fail to work.

Any idea on a static pressure spec? 

Is anyone else having issues with the email?

I've got:

server name: smtp.gmail.com
Server Port: 465
Use SSL: Checked
Username: full email address (ie. abc123@gmail.com)
Password: double checked correct (it's an application specific password since I have 2-factor on the email account)
From Name: name on gmail account
From Address: same as username
Send alert to Address: another gmail address (ie. def456@gmail.com)
Subject: Antminer Alert

I keep getting alert email failed notifications.  
No email received in my account.


this is with v5.1

No dead PSUs on any of my S4 units so far.  I have one that seems to flake out after a few days though and needs a power cycle.  When I do end up with a PSU issue, I'll look into it and see what needs to be repaired. I haven't even looked inside one.  Hopefully the components are easily repairable/replaceable using a soldering iron.  I'd hate to have to haul out the hot air rework station.

Well, I'm happy to report that my attempt at repairing the fans was a success.  I had quite a few fans that needed repair. I was never a big "fan" of buying fans.  Even in the old GPU days, I'd find tricks to repair the fans instead of buying new ones.

I ordered 3mm retaining rings from McMaster-Carr
http://www.mcmaster.com/#98541a111/=wdsnjk
$5.00 for a bag of 100 pieces

Also ordered the requisite pliers
http://www.mcmaster.com/#58225a21/=wdso3i
$16.98

Remove the sticker on the fan to expose the bearing and most likely a bunch of dried up grease and the old retaining ring that wore off. I found a few that look like the ring completely disintegrated because I was unable to find any evidence of an old one.



Remove the fan blade, remove the bearings, and carefully remove the spring from the shaft. Don't lose the spring
If the old retaining ring is still under the sticker and it didn't disintegrate you'll be able to see the wear that happened.  Here's a pic of a new retaining ring alongside a worn one.



I had to do some trimming of the retaining ring pliers since it didn't fit into the bearing area.  Used a dremel to carefully remove some material so that the fingers of the retaining ring pliers would reach into the hole.

Here's the pliers with one side done:


and then both sides:


I used denatured alcohol to clean everything well (the fan housing, area where the bearings sit, the bearings and the fan shaft).  Liberally dabbed some lithium grease on the first bearing that sits on the spring.  Don't place any grease on the other bearing until you have it seated and the ring installed.  Then hit it with some grease.  If the ring is not placed correctly, the fan will not spin frictionless. You'll feel and hear the shaft grinding.  If there's any grinding, the most likely culprit is that the ring isn't installed on the shaft groove properly. I used some gorilla duct tape to seal the end.

I averaged about 7 minutes per fan.

Thanks!  I just sent an email.  Was hoping to try repairing these myself so I don't have to keep bugging you guys with fan replacement requests.  Seems the ring might be a 3mm?  I've ordered 100 rings.  If they are the right size, I should be set for a while 

Well... I've gone thru another bunch of fans for my S4s.  Going to put in a request for replacement fans with Bitmain, but having taken one apart, it looks like they should be repairable.  Has anyone tried to figure out what size the retaining ring is that holds the fan spindle.  It looks like all these fans are failing similarly.  The ring pops off, probably due to wear.  I'm assuming it's metric.  Looks like 3mm. Just FYI, the second image shows the existing retaining ring popped back onto the spindle but it seems a bit loose and will probably pop off again.  I'm guessing the ring has worn down a bit, just enough to let it pop off.

See attached pics.