Topic: Antminer fire prevention (Read 1113 times)

There CRAP if its melting his sh!t!
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my kia forte  has a speedometer  the reads 120 mph  I can get it to that speed  on a downhill straightaway.

If the car  is pushed to those speeds it is unsafe.

The car can cruise at 80 mph for hundreds of miles with no issues.


Most of the miners are asking the molex  to do 120 mph  and not cruising at 80.

and they talk and think just like you wrote in the quote.

I don't mean to blanket genuine Molex connectors, my sentiment was that the "Molex" connectors used in nearly everything these days are very generic and god knows who the supplier is and their standards.  So, some relatively cheap Dielectric grease goes a long way in this situation.

The Molex PCIe connectors are *not* crap...
The only issue with them is in the past designers choosing to push more current through them than what they are rated to carry (for example KNC) and worse, not taking into account what is often mated to them eg, cheap (un-plated) or worn out PSU connector sockets with too-thin wire. When that happens of course they discolor and probably burn.

Stay within their stated ratings and use the correct gold-plated or at least gold-flashed socket pins along with decent 16ga wire and they work great.

If you take the steps above that I've outlined, you can be safe.  I've had them running for a while now.  I also felt the power cord to the wall and it was hot, so I changed to a higher gauge one that I had and was much better thereafter

Oh wow. It seems like dangerous to leave it on for the night.

I think that the materials for the common molex are crap and rated pretty low.  That's why they went to 3 connectors/hash board on the S7-S9.  Do those connectors even replace the ones on the PCB directly.

BTW, you can tell that it starts with one hot pin:

You can tell that it started with one pin getting very hot:

https://i.imgur.com/ZvPhP3n.jpg

Only 5 hours of mining at home on the wall plug w/ S5

https://i.imgur.com/rE54K46.jpg

Replace damaged connectors with new high quality ones. Rather than GPU type power connectors, you might want to look at using Anderson Powerpoles or R/C type high current barrel connectors. Those are rated for a lot more current.

So, I picked up a couple of Antminers S1-S5 and a couple of them had burnt out connectors.  The boards were fine and so were the headers, but the connectors were burnt.  It is a very good idea to use Dielectric grease to spread the thermal load across these connectors.  Dielectric grease works wonders in that situation. Air is actually an insulator, after a while it is like a convection oven. If you gap out the air and the grease spreads the thermal load, then the connector stays cool. Problem with plastics is that they have a critical autoignition temperature, once reach it they light up.  Take a lighter to an old Molex connector, you'll be surprised at how it will keep going once it is lit up.  Loctite sells a tube for $5 and makes for good insurance.

I also noticed that one of the connectors was getting especially hot out of four on an S5, I thought that part of the board had a particularly high current draw or something (this is after applying dielectric grease).  Nope, the connector was from the main bundle vs from the modular PCIe connectors.  Must be something about how the winding or the circuit is setup in the PSU I'm using. Doing a round robin of the connectors on that particular machine now has the connector temp relatively even.

I'm trying to see if anyone has a thread going or pics of the parts that fail on the board due to heat.  I'm wondering if coating them in some sort of thermal paste to spread the load would help them be more reliable.