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looking for a LiFePO4 UPS solution for modem/router

James in TN

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Mar 30, 2023
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central TN
I'm looking to find an all-in-one LiFePO4 solution as a UPS for my modem and router. My intention is to plug both devices into the power station's DC outlets rather than using the wall bricks that came with them. I'd even like to go so far as to keep the AC inverter shut off, if possible, as they will drain the battery uncessessarily.

The first device I tried was the Bluetti 600W EB3A. I charged it to 100%, then let it sit off while I was waiting for the male-to-male DC cables to arrive. After 1.5 weeks, the EB3A had lost 15% of its battery charge down to 85%, and that's with nothing plugged into it and the AC inverter off. Item was returned.

The device I'm going to try next is the Allpowers 600W R600. The odd thing that I noticed with this system is that it only turns on UPS when the AC inverter is turned on, not the DC outlets. So far, in testing, DC devices will remain on when the unit is unplugged from the wall with the AC inverter (and UPS option) turned off. It does make me wonder if the devices are being powered by the battery and not getting their power passed-through from the wall.

Perhaps I'm not looking at this correctly. Is the UPS option only really required for AC devices on these units? How can I be sure the power is passed-through when plugged into the wall rather than unnecessarily using the battery? (it does say 0 input with the DC device is running while plugged into the wall)
 
Look at the Wetown 1500 on Amazon, solid unit and works as a true UPS. Switchover time is fast and atm, it is priced at about the same $ as a high end mid-sized unit. Unfortunately, there aren't many units out there that really serve this function well in the mid-sized price range.
 
For mine I stick to the original plug packs.
I'm looking to find an all-in-one LiFePO4 solution as a UPS for my modem and router. My intention is to plug both devices into the power station's DC outlets rather than using the wall bricks that came with them. I'd even like to go so far as to keep the AC inverter shut off, if possible, as they will drain the battery uncessessarily.

The first device I tried was the Bluetti 600W EB3A. I charged it to 100%, then let it sit off while I was waiting for the male-to-male DC cables to arrive. After 1.5 weeks, the EB3A had lost 15% of its battery charge down to 85%, and that's with nothing plugged into it and the AC inverter off. Item was returned.

The device I'm going to try next is the Allpowers 600W R600. The odd thing that I noticed with this system is that it only turns on UPS when the AC inverter is turned on, not the DC outlets. So far, in testing, DC devices will remain on when the unit is unplugged from the wall with the AC inverter (and UPS option) turned off. It does make me wonder if the devices are being powered by the battery and not getting their power passed-through from the wall.

Perhaps I'm not looking at this correctly. Is the UPS option only really required for AC devices on these units? How can I be sure the power is passed-through when plugged into the wall rather than unnecessarily using the battery? (it does say 0 input with the DC device is running while plugged into the wall)
 
Look at the Wetown 1500 on Amazon, solid unit and works as a true UPS. Switchover time is fast and atm, it is priced at about the same $ as a high end mid-sized unit. Unfortunately, there aren't many units out there that really serve this function well in the mid-sized price range.
Thanks for this option. It's a bit big for my application, but I'll definitely look at it for another project.
 
Since it sounds like you can run everything with DC (12V?), why not just run everything off of a battery? Get a battery charger and keep it plugged in as necessary.
There is no worry/concept of cutover times, no unnecessary inverters or electronics powered up.
I wasn't looking to run 24/7 off the battery, only when the power goes poof. With that said, this suggestion may be what I end up doing indirectly. I believe that the power station will pass through to its DC outlets, so I shouldn't be using the battery if plugged into the wall. It appears to allow for seamless operation if I pull the plug, even without the AC inverter (and UPS) on. More testing will be required.
 
For mine I stick to the original plug packs.
The reason I wanted to use DC power for my modem and router when running off the battery is for efficiency. I believe it will run longer from the battery when powered from DC rather than AC. Also, the AC inverter itself drains battery life.
 
Yes, you have a small loss in two regulators if the devices aren't OK for LFP charge voltage, but it's pretty small, and a lot less than an inverter. If you run a 4S battery, any car adapter regulator will probably do the job. Since you likely won't care about a fast charge back to full, you can probably get away with a 13.6V float, which is probably within tolerance for most 12V router/etc.. In which case, you don't even need a secondary regulator, just a fuse.
 
The reason I wanted to use DC power for my modem and router when running off the battery is for efficiency. I believe it will run longer from the battery when powered from DC rather than AC. Also, the AC inverter itself drains battery life.
 
After a 2-hour outage last night I was researching this myself. I have some equipment that becomes a hassle when I lose power, and a few things appear to have actually been damaged.

Generally LFP isn't really the right solution for a UPS; you are paying a premium for high discharge cycles that you won't use. If you add in load shifting then there is a better chance it will make sense.

For me, I will likely end up with an LFP battery and DC-DC converters for equipment... but finding them has been harder than I expected. I'll cycle it every evening for 4 hours and charge it in the afternoon when I am over-producing solar. I need 12V, 19V, and regulated 48V for my system.
 
After a 2-hour outage last night I was researching this myself. I have some equipment that becomes a hassle when I lose power, and a few things appear to have actually been damaged.

Generally LFP isn't really the right solution for a UPS; you are paying a premium for high discharge cycles that you won't use. If you add in load shifting then there is a better chance it will make sense.

For me, I will likely end up with an LFP battery and DC-DC converters for equipment... but finding them has been harder than I expected. I'll cycle it every evening for 4 hours and charge it in the afternoon when I am over-producing solar. I need 12V, 19V, and regulated 48V for my system.

There are DC converters that can produce those voltages, but they are not cheap. ( $200 - 800 )

48 volt ones tend to be associated with telecom applications, so are inherently built very well to that standard.

The 12 volt regulated DC converters that are cheap are honestly not very good and have a lot of RF noise. The good ones cost about $0.30 - 50 / watt. I use them to make 12 volt regulated power in vans from 24 and 48 volt packs.

Honestly if you have 120 vac from your solar setup, just use it to make the DC voltages that you need for modest size loads with 3 regulated voltages.

I know that there are inverter losses, but for 3 voltages it is a lot of money for modest gain.
 
After a 2-hour outage last night I was researching this myself. I have some equipment that becomes a hassle when I lose power, and a few things appear to have actually been damaged.

Generally LFP isn't really the right solution for a UPS; you are paying a premium for high discharge cycles that you won't use. If you add in load shifting then there is a better chance it will make sense.

For me, I will likely end up with an LFP battery and DC-DC converters for equipment... but finding them has been harder than I expected. I'll cycle it every evening for 4 hours and charge it in the afternoon when I am over-producing solar. I need 12V, 19V, and regulated 48V for my system.
As well as serving as a 5KW @ 240v UPS...
The LFP I have gets used every night.
It supplies 300 W @ 240 V for 14 hours 365 days a year. If the power outage is at 4 AM in the morning I would still have enough left to cover the outage until I have sunlight.
It has been running 2 years. My payback on this particular setup would be 8 more years as I paid AUD $5000.
Subsequent copies have cost 1/2 of that.
Currently all of my Solar & Batteries together will be paid back in 5 years.
Whatever voltage of the power packs - my UPS system runs them. All the LED lights, routers, modems, TV's, phone chargers, security cameras, computers, Chromecast devices, fridges etc.
 
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There are DC converters that can produce those voltages, but they are not cheap. ( $200 - 800 )

48 volt ones tend to be associated with telecom applications, so are inherently built very well to that standard.

The 12 volt regulated DC converters that are cheap are honestly not very good and have a lot of RF noise. The good ones cost about $0.30 - 50 / watt. I use them to make 12 volt regulated power in vans from 24 and 48 volt packs.

Honestly if you have 120 vac from your solar setup, just use it to make the DC voltages that you need for modest size loads with 3 regulated voltages.

I know that there are inverter losses, but for 3 voltages it is a lot of money for modest gain.
My solar is AC-coupled, and currently no battery. I have APC and Cyberpower UPSs scattered throughout the house-- two in my office, two in the utility room, one for the living room, and one for the den. My problem is I actually need >4h of ride-through for at least three of the UPSs. I 5kWh server rack can easily do that; even 2.5kWh is plenty.

I really should just consolidate all server-type equipment in the utility closet rack and go for a single server rack battery plus a 1000W inverter/charger and be done with it, but there are a few bigger projects required to make it happen.
 
@Shimmy Maybe you can add or move some panels off to a DC based setup?

You are right that good quality AGMs can work just fine for what you are doing.

I have a 5000 / 48 quatro sitting around at my shop doing nothing. Supposedly it can generate the needed sine wave output to make an AC coupled solar array work, even when the grid is down. Have not tried it.
 
Check out this one: Unfortunately it is only available in South Africa and it doesn't have a brand.
I don't like to have Lithium-ion batteries in my home either. Especially when they are always being charged to 100% SoC.
Most available mini 12v ups's are based on Lithium-ion. The circuitry for a mini ups like this is relative simple. I think I am going to make my own one, based on Samsung or LG 18650 or 21700 LiFePO4 (LFP) batteries.
Anyone interested?
 
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Check out this one: Unfortunately it is only available in South Africa and it doesn't have a brand.
I don't like to have Lithium-ion batteries in my home either. Especially when they are always being charged to 100% SoC.
Most available mini 12v ups's are based on Lithium-ion. The circuitry for a mini ups like this is relative simple. I think I am going to make my own one, based on Samsung or LG 18650 or 21700 LiFePO4 (LFP) batteries.
Anyone interested?
If you haven't checked this out it might be an easier approach: https://www.mini-box.com/OpenUPS

Supports 5-24V output, most battery chemistries, 6A output, up to 6s battery. I have looked at them multiple times over the years but never pulled the trigger. (My equipment is generally centralized, so I end up needing a mix of voltages.)
 
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