13.8v computer

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^ Don't know about the computer.

If you buy a used UPS, get one without batteries. They are too heavy for shipping with batteries in them and are more prone to damage. And new batteries are cheap and ship cheap.

The battery stuff I suggested is for parallel setup, but really you should fuse it if you go 24V series with only two batteries. Whatever setup you choose, fuse it for sure. :)
 
Should I go 24v? That's a lot more money, because I have to get a stepdown "transformer", 24v charger, and a 24v solar charger for it. Is the gain worth it?
 
^ No. Just mentioned it cuz I didn't know what you were going to do in the end. A 12V parallel setup is probably the best bang for buck.

What is your objective? To be able to keep things online with full power failure?

My setup is for brownouts and surges to protect electronics, backup power for shop lights in case I'm out there working during a blackout. Short term power only, then it's over to generators. The 2kw inverter generator powers the 3KW UPS for all electronics and a 7.5 KW does the rest of the house.

With the computer on the links above it needs a monitor. What are you going to do for a monitor? Do LED/LCD's run on 12V?
 
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Out of order from your post, so I can get the flow I want.

^ No. Just mentioned it cuz I didn't know what you were going to do in the end. A 12V parallel setup is probably the best bang for buck.
Ok. Cool. 12V seems to be the cheapest to do, and the easiest from what I understand. I'll have to regulate it down if I do 24V or 48V, so I'm really not looking forward to those losses.

With the computer on the links above it needs a monitor. What are you going to do for a monitor? Do LED/LCD's run on 12V?
I already have a 20" 12v LED monitor, it draws about 2A peak, and that's totally within my "power budget."

What is your objective? To be able to keep things online with full power failure?
Really I just want to run everything on solar. Clean isolated power is key for HF operations. Being able to run in the event of a failure is also a good thing to have. I don't want to have to run on handheld radios unless I absolutely have to.

I just want to have an independent setup for when the power goes out, as it tends to around here. There have been enough times where after a minor storm we've lost power and cellular service. If there's snow added to that, I can't get up the hill for the exit to my cul-de-sac to get medical attention. Potentially, there's a stream that could flood and cut off my auxiliary exit, and that brings me to one other exit that doesn't involve hoofing it through the woods. Unfortunately that exit (we'll call this the main exit) is a road lined with trees and power/telephone poles. Potentially, I could be cut off from the world for several days.

My goal is to run comms equipment for three days with no replenishment charge: no solar, no mains, no generator, potatoes hooked up in series, saltwater and pennies, etc. If needed, I can wire in a small chest freezer on an alternator to keep essentials cool, and run it for a couple minutes a day as a fridge. I really can't see things going so far sideways that I would be without power for seven days, and at that point, I'm sure there will be sun to run everything.

So, there you have it. My reasoning and my goals.
 
I keep AA flashlights throughout the house - lithium batteries in them in case of night time power failure.

If there are Northern Tool stores in your area, or if not they have online shopping available. They have solar panels in the 12V format for some decent prices and run sales on them from time to time. Maybe you already have the panels? How much solar capacity? 100W? 200W?

I've never used them. Would wonder how well the charging circuitry is in them. Are you going to also maintain the batteries on conventional "Battery Tender" or equivalent? That may be the best way to go for longevity on the batteries and to ensure full charge condition in the event of a blackout.

A small backup generator could also be a lifesaver.
 
I'm going to buy somewhere in the range of 100-200w of solar panels, and a charge controller for them. Harbor freight/northern tool solar panels suck. They're big, in-efficient, and there's no warranty on their output. I'll buy some good panels and be done with it, rather than playing with crap from the get go.

I do have a battery tender, but in the winter it's hooked to the motorcycle, and I have a different float charger that I'm using right now to charge the batteries. I plan on keeping them topped off either via solar or mains if needed. It'll also help a lot with their life, even though WalMart has a 5yr warranty on them. :D

I have a harbor freight 1kW generator with a 12V output on it. I'm going to play with it today, it's the last Friday in the month, so it's time to start and run it for a little bit anyway. I'll play with the RPM settings and get it set to 13.8v on the DC side, since I really don't want to use it for 115vac with as much loss there is on the inverter.
 
Well, I went a different way. I have a chromebook 11 coming (charges off a 5v cell phone adapter) and I used a monster of a machine I already had but had forgotten about.

IMG_20140120_170026.jpg


So, yeah. Dual 20" (I think, maybe 22") displays, AMD A10-6800K quad core, 8gb ram, 80gb SSD, and an NVidia 9800 GTX dual headed card. Audio goes into a home built Tripath TA2020 based 2x20W amp, then is made sound through some parts express 6.5" 2-way speakers.

Total cost: $278 (chromebook 11 + cd-rw to burn debian on all other parts were free)
 
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