questions about DIY 12V battery backup

[rwb500]

I am going to build a 12V battery backup that will be connected to two MP60's and my Apex (just the 12V power to the Apex head unit). The goal is to keep oxygenation going for 24+ hours in my absence. Apparently the MP60's draw about 12W each at minimum speed. The Apex is 8W or less.

I believe everyone is connecting their equipment with a single common positive and a single common negative. But I noticed a lead-acid battery charger will reach 14-15 volts during charging, so the devices would also be seeing this increased voltage.

1. Does the charging voltage being over 12V cause any problems for the Apex or the Vortechs?

2. Does the Apex draw current through the 12V power supply if an EB8 is energized (normal conditions)? If yes, will this wear out my battery or my battery maintainer?

3. These are my tentative equipment choices. Thoughts?

Noco Genius 5A charger/maintainer


100Ah SLA battery

MIGHTY MAX BATTERY 12-Volt 100 Ah Rechargeable Sealed Lead Acid (SLA) Battery ML100-12 - The Home Depot

Delivering power when you need it, the MIGHTY MAX ML100-12 12-Volt 100 Ah uses a state of the art, heavy-duty, calcium-alloy grid that provides exceptional performance and service life in both float and

www.homedepot.com

Thank you

 

[fishguy242]

my be wrong ,but think you need dc to ac converter,i think amps will destroy equip,
hopefully others will chime in . @Eagle_Steve ? [USER=169459]@Lost in the Sauce

 

[KStatefan]

I use a voltage regulator in my setup for the part that goes to my controller(GHL). The part that goes to my powerheads (Tunze)is not regulated.

Have you looked at a LiFePO4 system instead of the lead acid?

 

[YOYOYOReefer]

i use a solar charge controller to charge my 400AH battery bank it also has backup to land based power and in worse case it turns on a generator. no issues with any 12 volt appliances, nothing is really 12v, should be called 14 volt. My pumps and equipment all hook to 120 volt coming off the sine wave inverter which runs off the batterys.. . If your backup power is set up right should be no isssues.

 

[rwb500]

smart ideas thanks guys

 

[Brian_68]

Yes, will need a 12 V DC to 120 V AC inverter to power the APEX / pumps. Don't forget the draw of the converters themselves as they can be significant and are not anywhere near 100% efficient depending on what is chosen. If the pump uses 12 watts it will be more than that coming from the battery.

 

[YOYOYOReefer]

its called an inverter, for the intended use, make sure to get a sine wave inverter.

 

[Spieg]

MP60s run on DC... no need to convert to AC and then back to DC again (this would be a tremendous waste of battery power).

 

[RobB'z Reef]

I'd seriously consider lifepo4. Yes it's a slightly higher initial investment but lead acid is ancient garbage. It'll work, but not for very long (2-3 years vs 5-10) and at a much higher capacity over time. A good pure sine wave converter should be about 97% efficient. You can build a system to go straight to the battery with everything and skip the power bricks but adding in fuses and possibly step ups when needed for 24v just increases complexity. But maybe that's ok too. An MPP with an inverter makes everything pretty awesome, safe and automated but it's a steep investment. A good ones I'd recommend is from MPP Solar. You should be able to run your pumps with the difference while charging without an issue.

 

[Jenuvio]

its called an inverter, for the intended use, make sure to get a sine wave inverter.

Yes. Make sure to get a pure sine wave. I have my lights and powerheads running on solar and one of my pumps failed due to using a modified sine wave. Note that a modified sine wave inverter will work but it shortens the life of your equipment if constanty running.

 

[Brian_68]

I'd seriously consider lifepo4. Yes it's a slightly higher initial investment but lead acid is ancient garbage. It'll work, but not for very long (2-3 years vs 5-10) and at a much higher capacity over time. A good pure sine wave converter should be about 97% efficient. You can build a system to go straight to the battery with everything and skip the power bricks but adding in fuses and possibly step ups when needed for 24v just increases complexity. But maybe that's ok too. An MPP with an inverter makes everything pretty awesome, safe and automated but it's a steep investment. A good ones I'd recommend is from MPP Solar. You should be able to run your pumps with the difference while charging without an issue.

They are only that 97% efficient if pulling a decent load typically 30-50% of rated and a specified type of load. Use a 500w inverter and only pull 5% (25w) the efficiency drops to 75% or even 50% in actual testing. Standby with no load is a killer for battery drain.

 

[FishyFishFish]

Why are people talking about inverters, to supply DC components?

 

[BZOFIQ]

Yes, will need a 12 V DC to 120 V AC inverter to power the APEX / pumps. Don't forget the draw of the converters themselves as they can be significant and are not anywhere near 100% efficient depending on what is chosen. If the pump uses 12 watts it will be more than that coming from the battery.

its called an inverter, for the intended use, make sure to get a sine wave inverter.

Absolutely NOT!. There is no point to convert it down to 12V DC to upconvert to 120V AC to downconvert it back to 12V. That's insane.

You need a power supply/charger to both supply power to your device and charge battery. In the event of a power loss you can power your pumps/apex directly from the battery.

 

[Brian_68]

Why are people talking about inverters, to supply DC components?

The APEX was mentioned as well and that is not DC.

 

[BZOFIQ]

The APEX was mentioned as well and that is not DC.

He is talking about powering the brain for monitoring during outages. - That's 12V DC

 

[DWill]

Use LiFe batteries and solar to charge them at least as a backup. I have my all my pumps running of off solar and LiFe batteries. Power from the house is the backup. The backup to all of that is a small generator that will run my return pump, heaters and my refrigerator and a couple lamps in the house.

 

[BZOFIQ]

I did exactly what the O/P is trying to do with both the 12 & 24V outputs. The Idea is to provide power and provide battery backup to DC Pumps and Powerheads along with apex and couple of other things using industrial power supplies and modules. These things are designed to operate in critical environments with quality far exceeding what is provided with your hobby grade equipment.

Here is my setup, not all completed in this picture as I dont have anything recent. It doesnt have to be this elaborate at all.

I setup similar for a friend of mine but on a much simpler scale. 2 SLA batteries, 10 Amp P/S, UPS Module and a DC Breaker.

Look at post #26 in this thread for some ideas. In addition to what I posted there you'll need 24V to 12V converter. These things can easily be found on ebay.

What are some of your favorite uses for breakout boxes?

I've heard nightmares about FMM so I found another way.

www.reef2reef.com

 

[RobB'z Reef]

They are only that 97% efficient if pulling a decent load typically 30-50% of rated and a specified type of load. Use a 500w inverter and only pull 5% (25w) the efficiency drops to 75% or even 50% in actual testing. Standby with no load is a killer for battery drain.

That's a good point thank you!

 

[ConectadoNZ]

I went with PO4lithium battery and I do power 2 MP40s, plus Vectra S2 using their fuse cable and the booster for the Vectra! When you add from the battery to the Ecotech controller that will be converted as my understanding so it’s all working as intended…