I just sold a noisy ups. The buyer replaced the fans and now it’s silent. Risk of death maybe worth it. Recommend a trained professional surf it but it does work
1 Like
Take a look at victron gear. It is all over 98% efficient, so it doesn’t need as much cooling.
For 2500w of load, you should have at least 5kwh of battery bank for stable power. ie:
1 Like
LiFePo4, “lithium iron Phosphate” batteries are now cheaper than lead acid car batteries (the cheapest lead acid batteries). And they last 15 years if you don’t baby them. Just don’t charge them when they are below freezing.
1 Like
I actually had this thought a few months ago and tried to order a pair of LiFePO4’s shaped like 12V9AH SLA UPS batteries from a Walmart.com marketplace seller, but they took the money and sat on it for weeks until Walmart auto-cancelled the order for excessive delay.
Lithium would solve the shipping cost problem, if they, you know, actually shipped. Perhaps I will try again. I am somewhat troubled by the absence of discharge current on most of the spec sheets.
The problem with that is that those batteries would have a maximum draw of 9 amps. 2 of them would give you a maximum power draw of around 216watts from the battery, or 190 watts from the inverter. Lead acid is good for high amperage short duration, which is why those UPSs often come with a cable to shut your computer down after 2 minutes. A single 12v 100ah lifepo4 can supply around a kilowatt for around an hour.
Larger problems need larger batteries:
or a generator.
I have 3 use cases.
1, we do trade shows, and vendor markets. Currently we are doing a weekly market that runs from 4PM to 8PM, plus an hour to pack and unpack. We get more sales because people can see our product. I run a 50ft 50 watt string light plus 3 19 watt spot bulbs doubling the light from the string. I was going through a car battery H7 80 pounds 70ah every 8 months to a year. The 100ah 12v lifepo4 battery should power this string for around 8 to 10 hours. Each battery is around 30 pounds and just as bulky as the lead acid car battery.
We live on the gulf coast and get both little and big storms that knock out power for a few hours to a few weeks.
The pair of lifepo4 will power internet at our house for a few hours, or an AC window unit for 2 hours.
The larger solar + battery I am building and my generator will at least partially power my house for a few weeks if needed. I am making an office space that can be used as a tiny house in an insulated shipping container in the back yard for next time it happens. So for we have had multi week power outages every other year.
That’s going to be pretty standard with UPSes of this size.
e.g. Eaton 9px6kva Datasheet says:
AC Mode Efficiency Rating (100% Load): 93
AC Economy Mode Efficiency Rating (100% Load): 98
I cant vouch for silence, because I’ve never even tried anywhere quieter than an office. As I said, it’s trivially easy to locate a UPS in another room. And most UPSes are needed in noisy environments, so practically no one cares.
I am an idiot when it comes to power. Give me a computer and I can do great things, but power… Not so sure about the magic thing.
You recommended the EG4 battery. I have a few questions about it. I am still looking for a 1500 watt (more is not bad, right?) UPS system for my office. My requirements are
- North American plug compatible
- Can handle high temperatures (110+ Fahrenheit)
- Cold temperatures are not a problem (I will not be anywhere where freezing temperatures are a thing)
- Countary I might be in humid areas like Central America
- At least 1500 watts of potential power consumption for my desktop/server equipment
- Office compatible (aka silent when not in battery mode)
- Won’t explode or kill me if I touch it (easy and possible to set up without being an electrical engineer)
- Rackmountable seems like a good option (I’d prefer an option that doesn’t take up too much space)
- Standalone (I’m still young, moving from apartment to apartment, and even considering moving to other Latin American countries, so I can’t have anything that’s a fixed installation)
- Affordable (for me this means not ultra mega crazy, but also not a lot of service requirements). I will probably be moving to a country where shipping is not easy, so I need something that will not break. If I have to pay a premium for that, but not have to drive the battery back to civilization just for service, I consider that a win.
- Other than that, I want the battery to last as long as possible for my budget. I need at least more than a 10 minute UPS because I not only want to get through the power loss for a safe shutdown, but also until the power comes back.
Is the EG4 battery what I need, or what would you recommend for my situation?
Also, I saw you recommended the EG4 somewhere else, are you affiliated with the company? Just asking for transparency.
1 Like
EG4 isn’t a “bad brand” but your concern is quite valid. Maybe something like this would be too big for you, but he does other builds too and the smaller version he shows might be right for you.
do note however, the bigger power inverters do make noise… but that can be compensated for relatively easily.
2 Likes
Will prose in the linked video is right on the money. He reviews the hardware, then runs it to spec and beyond. When I first started watching him he was reviewing solar systems for his mobile home, which was a big upgrade from being homeless. For the most part he has his priorities right. He tells you what works, what doesn’t, and why. How to do it safely and what is a waste of money. He reviews an ecoflow home system then a week later shows you how to build something with twice the capabilities for half the price, though you will need to a bit more work, like crimp some of your own wires.
I am not affiliated with any vendor but I am going to pull the trigger on building a solar system before next summer. As such I price compared all of the options I have been able to find, and signature solar is often 20% to 60% the price of their closest competitor who will sell to people doing diy work.
2 Likes