About that reliability !Harbor Frieght

Alternative energy sources
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The usual. As I have two large solar PV systems here, and my lab assistant just put one in, and others are interested in things like this, here's where that stuff goes. This is mostly for things that work now, not "gee someday a fusor will do this" -- we know that, but it's not someday yet.
The hope is to save anyone embarking on this sort of thing a lot of wasted time and money, as at least I have been off the grid since 1980 and have had a lot of practice (and made mistakes you won't have to).

About that reliability !Harbor Frieght

Postby Doug Coulter » Wed May 13, 2015 10:52 am

Well, I had my very first unplanned downtime for the power system last night. I was in a G+ hangout and one of the guys estimated it to be around 10 minutes. I can now calculate 9's, as I have an actual failure - one data point doesn't say all, and things are slightly complex, but here goes.

I've been at this since 1979. We're about halfway through 2015, so being generous, that's 35.5 years.
60*24*365*35.5 is 18658800

It might have been more like 5 min but who knows. So subtract 10 min from the above number, and use it as the numerator, with the original as the denominator, and you get: 0.99999946406

Which shows for one thing how darned hard it is to get to high nines - doesn't take much downtime to ruin a perfect record, but hey, this ain't bad.

FWIW, neither the laptop I was doing the hangout on, or may "lan of things" data aq went down - they have their own batteries, respectively. But everything else did. Proximate cause was low batteries, and the cause of that was a burst plastic hose on my compressed air system that caused the compressor to run continuously (5hp). I'd stupidly left the air system on; I have shutoff valve that keeps it from running when I don't need it. I needed it for some shop work I did for a guest, and simply forgot to turn the valve back off. This would normally have not mattered, as I used to live in that building too, could hear the compressor run, a and the hose that popped was right next to my normal hangout couch - I would have jumped halfway out of my skin and run down to shut things off, but I've moved 30 yds away...and didn't hear it.

Obviously (well, I already knew this) my lan of things needs more nodes - for battery monitoring, load and input, the usual temperatures, weather and so on for that building, and perhaps a remote ability to turn the real power hogs off from the lan.

Again, the main point of that project is that I used to have to notice every single thing and take care of it manually - and I forgot something that was "free" because I don't live in that building anymore. Now monitoring that shop isn't free - I have to go over there, or use computers/sensors to get it done for me. It was of course, the other direction before I moved here (so I can remote control the fusor from a radiation-safe distance) but no matter, the concepts and goals are the same.

A sort of interesting anachronism - bringing modern tech to the age old art of homesteading. It does work if you do it right.
And I didn't lose even a single data point from the data-set I'm already taking, since that stuff has it's own UPS. Heh.

Yes, I had to go run a generator - letting batteries sit low is bad for them, though the terminal voltage came right back up without that huge load - I felt it wise to bring them to a decent level of charge, so trickled them overnight...and now the sun has done the rest. I think that was gentler than what the sun alone would have done as well, since it's a gonzo maxed out system that would just have started putting a couple hundred amps into the batteries the instant it could...the generator I used is more like 15 amps net of the campus loads.
Posting as just me, not as the forum owner. Everything I say is "in my opinion" and YMMV -- which should go for everyone without saying.
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Doug Coulter
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Location: Floyd county, VA, USA

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