Battery Backup DIY

[lpramos]

I'm following the excellent thread below on prepackaged systems for small Wh, but I need to go BIGGER.

Battery Backup

I'm looking for opinions and help regarding automatic battery backup. What do you use/suggest, etc? I have a jackery for backup but I still have to manually plug things in. I am looking for something that would automatically trigger on if a power failure is detected. If that is something...

www.reef2reef.com

I need advice on how to keep power for at least 2-3 days+ after a storm/hurricane. I'm in an apartment in Ft Lauderdale, so I can't have a generator. All of my equipment is DC (mostly Sicce), so I don't need an inverter. I don't need my heaters or lights powered, because Florida.

Can you all please comment on the schematic attached?

Meanwell has good power supplies. Victron has a good shunt and 12V DC to 24 V DC converter. I'm OK with the chinese LiFePO4 batteries, since there are good teardowns, tests and recommendations on YouTube.

But, I can't find a suitable DC to DC transfer switch. I found the "Automatic Emergency Power Switch, DC 12V 12A 150W AC Backup Battery Switch" on Amazon, but I'm not sure I trust it.

Same for the "DC Power Distribution Module, Rocker Switch, Fused, Pluggable Top Wiring Terminal Block, DIN Rail and Screw Mount (4 Channel)"

I don't like the expense of the Kraken and I don't like the 24V to 12V step down on battery backup. I'm a novice to electrical, but I like to assemble custom/tailored systems.

All comments are welcome.

@VintageReefer
@Tamberav
@Beruka
@Dragen Fiend

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[Dragen Fiend]

Personally I would just do a power station. But if you insist...

Hmm not sure how this will play out. Your devices are a mixture of 12v/24v. Your using AC 120v power supplies to convert to DC 12v/24 for output. You also want DC to DC for battery backup.

Just from your power consumptions: Your looking at 4kwh per day to keep things running.

I dabble in electronics myself however my designs are never efficient lol.

I would remove the power supplies that come with the components and use meanwell power supplies.
For cheap but good batteries I'd get from batteryhookup. I've been shopping there for years for my DIY projects.

Wall outlet-----Meanwell 24v 14.6A power supply- use a step down for 12v. Always use higher voltage and step down when needed.

Amazon has tons of DC auto transfer switches. Pick your poison.
This would work fine for the application. If you need something beefier look around.
DC transfer switch

You really don't need a distribution board unless you want a organize look. I'd just hook it all up to the meanwell power supply and the DC switch as long as its all rated to handle the current. Though the size of the cables may indeed make you need a breakout


For me it would go

Wall outlet----Meanwell 24v 14.6a---DC transfer switch 24v main terminal 1 ---- 1,2,3
main terminal 2-----24V to 12v step down---4,5,6
Wall outlet- battery charger- 4kwh-12kwh battery 24v-----------DC transfer switch backup terminal 1----1,2,3
backup terminal 2---4,5,6

 

[lpramos]

That's all good advice, thank you. I've been reading 24V is better. Yes, I'm going with the single large Meanwell brick.

Roughly $800 for a power station will give me ~1000 Wh. The same coin can get me over 3000 Wh DIY. Cables and connectors excluded from both. You might consider it. Again though, I'm a novice and I don't know what I don't know.

Thanks again.

PS. Yes, lots of kWh. If a hurricane laid waste, I would turn off everything off but the Sicce XStreams.

 

[Dragen Fiend]

That's all good advice, thank you. I've been reading 24V is better. Yes, I'm going with the single large Meanwell brick.

Roughly $800 for a power station will give me ~1000 Wh. The same coin can get me over 3000 Wh DIY. Cables and connectors excluded from both. You might consider it. Again though, I'm a novice and I don't know what I don't know.

Thanks again.

PS. Yes, lots of kWh. If a hurricane laid waste, I would turn off everything off but the Sicce XStreams.

Yea I'm a big fan of DIY for batteries and solar. Though at this scale. It would make more sense to get a subpanel and hookup a dedicated inverter/batteries to the circuit you need to power your tank.

I paid $1300 per 5.12kwh.