How to start S9 fans before the actual controller / boards (humid environment)

[VentMine]

Lets say I have 20 or so S9's on a rack, and the internals have collected condensation due to sitting idle in a cool, humid environment.

Don't worry about why... 

What is the easiest way I can rig up each S9 such that the fans start up prior to actually starting the controller and boards? Could I add some kind of relay or something?

I have a situation where there's nothing I can do to prevent condensation on the internals, as the miners will periodically shut down and they are located in a humid environment. If I can just first power the fans for a bit (before the miner itself fire up), I'm thinking the airflow will dry up the internals pretty quick and avoid a possible short-circuit. Using an external controller, I can then switch on the circuits to start up the miners once they are dry.

Any idea's?

[VRobb]

How do the internals of your miners get below the dew point of the air they're in? Might not be a scenario that's actually possible.

[NotFuzzyWarm]

I take it the miners are sitting directly in front of the cold air vents feeding the area as spot cooling? I've seen a lot of rather horrid industrial shop-floor environments at that is the only way I've see it happen to power equipment that has been powered down for a while... Partly for this reason you never ever want to duct cold air directly onto/into power electronics.

IF that is the case either move them or deflect the airflow around them as pre-heating or running the fans does not address the root problem.

[VentMine]

How do the internals of your miners get below the dew point of the air they're in? Might not be a scenario that's actually possible.

Because they are not housed in a conditioned building, they are housed in a shipping container open to the elements.

I take it the miners are sitting directly in front of the cold air vents feeding the area as spot cooling? I've seen a lot of rather horrid industrial shop-floor environments at that is the only way I've see it happen to power equipment that has been powered down for a while... Partly for this reason you never ever want to duct cold air directly onto/into power electronics.

IF that is the case either move them or deflect the airflow around them as pre-heating or running the fans does not address the root problem.

There is no ducting directly into the miners, but see response above to VRobb. When the mine is running, there won't be any issues. My main concern is when it is shut down (it will periodically be shut down, more frequently than a typical mining farm) the entire container and mine will cool. Once cooled dew and condensation will occur. I do have a back-up heater in place, but, there will also be times when it too doesn't have power.

So any idea's on how to rig up the miners so the fans can turn on first, as per my OP?

Cheers

[VRobb]

Well the easy way is you disconnect the power and i/o cables to the hash boards, power up the controller which powers the fans. The fans will run, though slowly since the temp sensors will show nothing, and run like that until you're confident you can power up the hash boards. Once you feel enough time has elapsed, power down. Reconnect the power and i/o to the hash boards and crank them back up.
What's that? You got more than a handful of miners?? And this may happen at any random time?? 
Don't know about that, still think way inside your container and inside the miners themselves there won't be any condensation of concern when powering up after any long down time. I'd think most moisture would be on outside surfaces, both container and miners.
But that's just my opinion, I could be wrong. 

[HagssFIN]

Humid environment is still a big risk for your miners with corrosion risk and etc.

[VentMine]

Well the easy way is you disconnect the power and i/o cables to the hash boards, power up the controller which powers the fans. The fans will run, though slowly since the temp sensors will show nothing, and run like that until you're confident you can power up the hash boards. Once you feel enough time has elapsed, power down. Reconnect the power and i/o to the hash boards and crank them back up.
What's that? You got more than a handful of miners?? And this may happen at any random time?? 
Don't know about that, still think way inside your container and inside the miners themselves there won't be any condensation of concern when powering up after any long down time. I'd think most moisture would be on outside surfaces, both container and miners.
But that's just my opinion, I could be wrong. 

I hope you are right, would sure make things easier.

[Elphamyto]

You may be able to do something that's automated from a host server/computer. Assuming you've assigned them all static ip addresses, you could run a bash script (shortly after powering on all the units) that would ssh into each miner and run a command like "killall -9 bmminer"

If the fans are left running after killing bmminer then there shouldn't be much (if any) current running to the ASIC's. Once the fans have done their job you could just run a second bash script that would ssh into each miner and reboot it.

[AtraxPool]

Get yourself a Dehumidifier! 

Electronics and damp do not get along and could casue a fire risk!

[leowonderful]

Get yourself a Dehumidifier!  

Electronics and damp do not get along and could casue a fire risk!

This. They usually don't cost too much and for a few bucks more you can get a dehumidifier that automatically empties itself. Not much need for anything else in this scenario IMO.

[VentMine]

You may be able to do something that's automated from a host server/computer. Assuming you've assigned them all static ip addresses, you could run a bash script (shortly after powering on all the units) that would ssh into each miner and run a command like "killall -9 bmminer"

If the fans are left running after killing bmminer then there shouldn't be much (if any) current running to the ASIC's. Once the fans have done their job you could just run a second bash script that would ssh into each miner and reboot it.

Interesting idea, I will consider this thanks for the suggestion!

"you could run a bash script (shortly after powering on all the units)" - Hopefully at this point not much current is running into the hashing boards (?).

[VentMine]

Get yourself a Dehumidifier!  

Electronics and damp do not get along and could casue a fire risk!

This. They usually don't cost too much and for a few bucks more you can get a dehumidifier that automatically empties itself. Not much need for anything else in this scenario IMO.

This is not an option for me. When the mine is powered down I will have no access to power *at all*, so I can't run a dehumidifier.

Sorry I haven't completely elaborated on the constraints I'm working with. I basically have no options to dehumidify or isolate the miners during a shut-down, because I will have no power. My only option to mitigate condensation is after I regain power. One obvious option is to first start a dehumidifier and or heater, to get rid of condensation, but this means I will have to wait X amount of hours before I can safely start up the miners (remotely too, no one will be able to physically be present).

The best solution I can think of is to somehow start the miner fans to reduce this down-time period after power is restored.

I appreciate the idea's so far, thanks guys!!

[Didley1JT]

Get yourself a Dehumidifier!  

Electronics and damp do not get along and could casue a fire risk!

This. They usually don't cost too much and for a few bucks more you can get a dehumidifier that automatically empties itself. Not much need for anything else in this scenario IMO.

This is not an option for me. When the mine is powered down I will have no access to power *at all*, so I can't run a dehumidifier.

Sorry I haven't completely elaborated on the constraints I'm working with. I basically have no options to dehumidify or isolate the miners during a shut-down, because I will have no power. My only option to mitigate condensation is after I regain power. One obvious option is to first start a dehumidifier and or heater, to get rid of condensation, but this means I will have to wait X amount of hours before I can safely start up the miners (remotely too, no one will be able to physically be present).

The best solution I can think of is to somehow start the miner fans to reduce this down-time period after power is restored.

I appreciate the idea's so far, thanks guys!!

I'm curious why you can only have power when the miners are on. Can you elaborate?

[BitcoinIntern]

Can you use some kind of redundant power to power up the dehumidifier? In such a way that those puppies start when the power goes off. I don't think it should be that difficult. Thanks.

[AtraxPool]

Why not take the fans from the miners and hook them up to a relay and speed control switch. that way you can turn them on alone first to dry out the miners then once ready you can power up the miners and hand control of the fans back to the miner?

But note if you do this you will be pushing cold air over damp electronics.  I highley recomend you find somewhere that is more suitable and less dangerous!

[Steamtyme]

I was thinking since you obviously have power restored by the time you are planning on drying out your miners. You may want to set up a few different fans to blow onto your miner set up, once everything is up and running with a dehumidifier or 2.

Another option is looking into Desiccant trays/bags/packets placed throughout the container during layup periods. It is what is used inside boilers during dry layups during prolonged downtime, to prevent moisture and corrosion.

I would also look into trying to seal whatever you can to reduce the exposure to the elements during these periods; and as much as you can during operation.

[BitcoinIntern]

I take it the miners are sitting directly in front of the cold air vents feeding the area as spot cooling? I've seen a lot of rather horrid industrial shop-floor environments at that is the only way I've see it happen to power equipment that has been powered down for a while... Partly for this reason you never ever want to duct cold air directly onto/into power electronics.

IF that is the case either move them or deflect the airflow around them as pre-heating or running the fans does not address the root problem.

So you are saying not to pull direct air from outside? How should it be done then? I always thought that pulling in direct cold air from outside is the way to go...Thanks.

[Steamtyme]

I take it the miners are sitting directly in front of the cold air vents feeding the area as spot cooling? I've seen a lot of rather horrid industrial shop-floor environments at that is the only way I've see it happen to power equipment that has been powered down for a while... Partly for this reason you never ever want to duct cold air directly onto/into power electronics.

IF that is the case either move them or deflect the airflow around them as pre-heating or running the fans does not address the root problem.

So you are saying not to pull direct air from outside? How should it be done then? I always thought that pulling in direct cold air from outside is the way to go...Thanks.

I think the point is to not have the cold exterior air blowing directly onto the miners, especially once powering them down, as they are the first surface the air touches, and that's where the condensation will occur.
Have the air come into the space, but direct it in such a way as to lower the overall temperature in the space.

[AtraxPool]

I take it the miners are sitting directly in front of the cold air vents feeding the area as spot cooling? I've seen a lot of rather horrid industrial shop-floor environments at that is the only way I've see it happen to power equipment that has been powered down for a while... Partly for this reason you never ever want to duct cold air directly onto/into power electronics.

IF that is the case either move them or deflect the airflow around them as pre-heating or running the fans does not address the root problem.

So you are saying not to pull direct air from outside? How should it be done then? I always thought that pulling in direct cold air from outside is the way to go...Thanks.

I think its more important to vent the hot air from the miners than bring cool air into the room if you are having issues with dampness.  If you can manage room temps by exhausting then your intake can be less as there is not so much heat to deal with meaning less chance of dampness on the boards..

On the other hand if you are in a damp area then more cool air is only going to make the problem worse.

You really should be looking into a better place for them why risk your equipment in a area that sounds very unsuitable for mining.

You might spend a fortune and a long time trying to make a stable area for your miners when you could probably find somwhere better and not have all the additional work.

[VentMine]

Why not take the fans from the miners and hook them up to a relay and speed control switch. that way you can turn them on alone first to dry out the miners then once ready you can power up the miners and hand control of the fans back to the miner?

But note if you do this you will be pushing cold air over damp electronics.  I highley recomend you find somewhere that is more suitable and less dangerous!

So this is the kind of answer i'm looking for, thanks Atrax. Can you elaborate on a potential set-up as you describe but controlling 30-70 S9's? What would be the most efficient set up to power all 30-70 fans using this relay-switch configuration?

Unfortunately, my source of power is cheap but I have 0 alternative options for alternate set-up. I'll elaborate on what I'm doing specifically in a later post, for now I'd prefer to keep it undisclosed until I can test it out.

I was thinking since you obviously have power restored by the time you are planning on drying out your miners. You may want to set up a few different fans to blow onto your miner set up, once everything is up and running with a dehumidifier or 2.

Another option is looking into Desiccant trays/bags/packets placed throughout the container during layup periods. It is what is used inside boilers during dry layups during prolonged downtime, to prevent moisture and corrosion.

I would also look into trying to seal whatever you can to reduce the exposure to the elements during these periods; and as much as you can during operation.

-Yes setting up fans could work but activating the S9's fans would be far more efficient.
-Good idea on the Dessicant! It's not ideal as it adds to the operating cost / overhead but it might be something I'm forced to do.

Thanks for the helpful feedback everyone. It's too bad I can't just modify the firmware to only power up the S9's fans on start-up (?).