Topic: ANTMINER S4 Discussion and Support Thread - page 120. (Read 301481 times)

Okay so my B2 S4 arrived yesterday, plugged it in, manually set difficulty and I'm off to the races - no problems.

Got the email about the PSUs - confirmed shipping just now for a new one, but in the meantime, do I need to be worried about the PSU I'm currently running burning my place down??

It is worth noting that although a failed output MOSFET at high temperatures may result in some smoke from the PCB and thermal pad, it will not start a fire. All internal components of the PSU meet the requirements of the UL94-V0 flame retardancy standard, which certifies that any ignition will self-extinguish within a maximum of 10 seconds.

For your part dogie, you seem very quick to jump on anyone suggesting that there is a hardware issue which only exacerbates the problem now that you're a paid rep for the company. I'm having a hard time faulting you for being a little defensive given the vitriolic attacks against you that are unrelated to the issues at hand, but not everyone that comments on these posts is attacking you or Bitmain. People just want to see the problem resolved.

Unfortunately I set it up and went to work, finding out about the PSUs afterwards. Hopefully I still have a home to go to. lol

Dear loyal customers,
Today we have found out that the batch of power supplies shipped out in batch 1 and the first part of batch 2 Antminer S4s contain a critical defect. The customized power supply produced by AplusPower Co. Ltd is suffering from an unacceptably high failure rate and will be replaced with immediate effect.
We take full responsibility for the problems caused and had not anticipated the unique loading conditions of a miner when selecting and testing the suitability of these power supplies. You can read more about the defect in the post below.
We are now taking steps to ensure that customers are impacted as little as possible. The rest of batch 2 S4s will come with the improved power supply as standard.

The following actions are being taken for miners already delivered:
1)  If your PSU has already failed:
•   Submit a RMA request with some pictures and proof [ie with your username in the photo] of your PSU’s failure to [email protected].
•   We will then ship a new PSU out as soon as possible.
•   We will also issue compensation to the value of 10 days of mining profit calculated starting from shipping date
2) If your PSU has not failed and the miner is running normally:
•   We will ship a new PSU to you.
•   Please do not contact support yet, you will receive an email asking to confirm your shipping.
      

---

Analysis of power supply failures within the first batch of Antminer S4s

We are sorry for the inconvenience you may have experienced regarding power supply failures, or even sporadic events of smoke from our first batch of Antminer S4s. We immediately set out to investigate the reports of failed power supplies from customers, and have made immediate changes to improve the quality of future deliveries. What happened with these power supplies is not acceptable.



The power supplies failed by two different mechanisms:

1) Failed TR1 or TR2 MOSFETs on the power factor correction (PFC) circuitry.

After investigations, it was found that the unusual service conditions a miner puts on its power supply was the cause of the failure. The repeated abrupt, dynamic loading generated significant current through the PFC circuits, eventually leading to the failure of the TR1 or TR2 MOSFETs.

The replacement power supplies have significantly upgraded PFC circuits in order to improve performance and prevent a recurrence of the problem.


2) Failed MOSFET on the output Synchronous rectifier circuit

A MOSFET on the output Synchronous rectification circuit was also found to be failing, due to the repeated and sudden load changes during the miners’ operation.

During normal operation, the output MOSFET is expected to carry a current of approximately 30A and operate at a surface temperature of around 80C. The failing MOSFET was found to be heating up significantly further than this, causing the carbonized black PCBs and smoking thermal pad.

It is worth noting that although a failed output MOSFET at high temperatures may result in some smoke from the PCB and thermal pad, it will not start a fire. All internal components of the PSU meet the requirements of the UL94-V0 flame retardancy standard, which certifies that any ignition will self-extinguish within a maximum of 10 seconds.

In response to this problem, the sample filter in the Synchronous rectifier circuits have been altered to erase the excessive current, and so the MOSFET will not fail again. In addition, several high temperature prevention circuits have been added which will better protect the power supply from overloading and excessive temperatures.


Moving forwards

We always perform significant dynamic testing on chosen power supplies, however in this case we failed to recognize the special conditions and specific loading characteristics the miner would place on the power supply. Our testing has been altered to replicate and include these loading characteristics on any power supplies introduced in the future. Once again, we are sorry.

As long as you can have watch your miner..... Better safe and get Fire hydrant and smoke detectors. Dont leave the house unattended.

Just disagreeing with the people saying it can't be fixed with firmware. Open sourcing is a decision which someone higher would have to do.

Okay so my B2 S4 arrived yesterday, plugged it in, manually set difficulty and I'm off to the races - no problems.

Got the email about the PSUs - confirmed shipping just now for a new one, but in the meantime, do I need to be worried about the PSU I'm currently running burning my place down??

More off topic stuff, but forced to reply to the lies...

1) Yes, I have a masters in mechanical engineering - you just repeating "no" does not remove my degree :/
2) No its not from MIT
3) I've been financially independent from my parents for the last 7-8 years.
4) I never lied that I was/am/will be paying for college....
5) I've never forced anyone to donate, even for any of my guides...
6) If people want to donate, they can do. In the last 18 months donations have not exceeded $200 or so.
7) It was in £
It was sales. I don't know about you but I don't want around donating companies by their net worth.
9) Post a scam accusation, this is all off topic.

You have a BEng in Mechanical Engineering? I have a Masters (MEng) in Mechanical Engineering, you are a million miles away being qualified for this - you're going to have a rude awakening once you do more research. [I too I am unqualified for this....]

4 years of engineering and a 2 year MBA at Harvard/MIT = big bucks. Your attempt at logic was a good try though.

Yeah, he did. Not sure what you're disagreeing with, the issue isn't resolved at this point and is contingent on Bitmain fixing their driver.

Alternately, when you talk to them you should bring up the possibility of open sourcing their chip protocol and driver source. It would solve a lot of their problems.

Its a problem while we're waiting for a firmware fix / hack. For now, put it onto BTCGuild / Ghash / Slush's and set difficulty manually to 2048.

But he did say:

Says who - the bitmain messenger boy who's paid to deny everything negative?

Waiting for Bitmain to release firmware fixes can be a long, drawn out affair, as S2 users will confirm. Hardware issues can't be "fixed" by software patches - anybody with the slightest understanding of software/hardware knows that. Which is probably why you don't......

But he did say:

You can keep quoting this, but he issued a firmware fix which 'fixed' it, and Bitmain will issue their own firmware fix soon.

They just need to get off their arses and fix their driver which appears broken.

You can keep quoting this, but he issued a firmware fix which 'fixed' it, and Bitmain will issue their own firmware fix soon.

Unfortunately not. I tried a simple hack on their driver and it only partially helped. They just need to get off their arses and fix their driver which appears broken.

NO you did not you little lying piece of shit. You got a master degree in less than a year? from MIT? while living in your mom's basement in UK?

The fact that you lied to get ppl to "donate" money while fcking brag about building a $1Million company at age of 13 does not make you a scammer? There is a reason why the forum prohibits begging now, to block fcking pathetic liar like you. There is nothing random about you, everyone here long enough knows what a joke you are.

Ckolivas was quoted a few pages back about it:


EDIT: Which presumably means that it can't be fixed by any new firmware releases - it's a hardware issue.

How can we confirm if we have the defective PSU if it hasn't failed yet? And how would it work if we are buying from a reseller, do we still get the new PSU ship directly to us or the reseller gets it?

Please describe how we can tell the difference from a defective PSU S4 model, and a non defective PSU S4 model, before they get defective.