DIY Universal Battery Backup For Your Reef

[Finatik]

@Finatik Inverter/chargers are not my personal preference, but they will certainly work just fine for this application. It's really all you will need beside a battery. It incorporates all the parts you need to make this system work. I would only order 1 inverter/charger, unless you plan to have a separate battery/battery bank for each. Since each inverter/charger will try to charge the batteries when the power is on, you may get some unexpected results from two chargers trying to run at once. Unless they're dumb float chargers and all they do is float the batteries to a certain voltage. But unfortunately, there's no way to know what mode of charging these things will use.

The batteries will be the real deciding factor in how long your system runs. Ideally, you should get a Kill-A-Watt to measure how much power all the components you want to run will draw. Because you're talking about a rather expensive system, I personally would not try to plan capacity without knowing exactly how much power you need. If you use Apex controllers, you might be able to tell your power usage from the controller.

If I can talk you out of running the heaters on the battery backup, I would. Unless you live in a cold area, the tanks will likely not cool down very much. Additionally, heat is not usually an emergency unless we're talking about several days of power loss and very cold temperatures (in the 60*s). There's no reason you couldn't run the heaters on batteries, but it's going to eat a lot power.

I've created a calculator to make finding the power requirements of battery backup systems easier. It can be found here. Simply plug in the wattage of your equipment, how many hours you want it to run, and the calculator will give you the amount of amp hours you need. The inefficiency and discharge limits can be changed, but those two values are good estimates. If we use 100W as your load and a 24 hour run-time, the calculator says you need 275 Ah of battery power. This battery is 100Ah, so you would need three of them in total (100Ah * 3 = 300Ah) to run 100W for 24 hours. You'd need to double the batteries for double the run time. Conversely, you could double the run time by reducing the load in half (running only 50W of equipment instead of running 100W).

If we assume your 1000W heaters only run half the time, they would increase the amount of batteries you need by roughly six times. The costs really start to add up quickly if you want 24-48 hours of run time. In my case, I run a 7W pump in my sump and a 7W pump in my display (a Koralia 425 and Jebao PP-4), so a single 100Ah battery will give me 60+ hours of runtime. You can certainly buy as many batteries as you can afford and this system will work. But at a certain point, a solution like Tesla's Powerwall may actually be more economical.

Hi @chipmunkofdoom2 and @Brew12

So I've already purchased two of the 2000W Inverter/Chargers by Renogy (one for each of my 120Gs).

@chipmunkofdoom2 you mentioned that this particular model wasn't your personal choice. Why ? Is there something wrong with this particular model ?

Can the Inverter be out in the open inside my fish room, or should I build some type of enclosure for it ?

Also, what type of unexpected results might I encounter from running both of them at the same time ? If there is a prolonged power outage, I will want to be able to power the critical components for both of the 120Gs to keep my tank inhabitants alive. I plan to have seperate batteries for each one.

Lastly, is there a particular battery that you recommend I use with the Inverters I have in order to achieve the results I'm looking for (as mentioned in my previous post above) ?

Sorry for all of the questions, but I just want to make sure I do this correctly AND in the safest manner.

Thanks again for your input and assistance with this. You guys are awesome !

 

[Brew12]

@chipmunkofdoom2 you mentioned that this particular model wasn't your personal choice. Why ? Is there something wrong with this particular model ?

I don't believe his preference is because of this model. I believe he prefers separate battery chargers that aren't built into the inverter. You get better control of how the battery is charged that way. These should be fine since they have presets for each type of battery but you don't have the control.

Can the Inverter be out in the open inside my fish room, or should I build some type of enclosure for it ?

I would leave it in the open. These things can generate some serious heat so an enclosure would be less than ideal.

Also, what type of unexpected results might I encounter from running both of them at the same time ? If there is a prolonged power outage, I will want to be able to power the critical components for both of the 120Gs to keep my tank inhabitants alive. I plan to have seperate batteries for each one.

With separate batteries, they will be fine. If you connect them both to the same battery sets it can cause all sorts of dangerous issues.

Lastly, is there a particular battery that you recommend I use with the Inverters I have in order to achieve the results I'm looking for (as mentioned in my previous post above) ?

I would use a marine deep cycle battery designed for 12V trolling motors. Brands are much less important than they used to be imo. You can get them at most auto parts stores or even at Walmart.

 

[chipmunkofdoom2]

@Finatik @Brew12 is spot on. It's not that particular inverter/charger that I don't like. I'm just not a huge fan of inverter/chargers because they package everything into one device (charger, inverter, and transfer switch). If any one of those parts breaks, then the inverter/charger is toast. Unless you have a really good warranty. In a complete DIY system, if your charger fails, you can get almost any smart charger designed for your batteries. If the transfer switch fails, just get a new one. If the inverter fails, any inverter with similar power rating will do. As Brew12 also pointed out, the way that these devices charge the batteries is usually an unknown (they likely just float to 13.2 - 13.6VDC or so). I personally prefer to have a multi-stage smart charge as opposed to just floating the batteries to a set voltage. A quality AGM battery will last you up to 10 years if you don't cycle it too hard and avoid sulfation, which a quality smart charger will do. Lastly, a DIY system tends to be cheaper. A 2,000W PSW inverter alone will run you around $200 - $400, depending on the brand. Add a $30 battery charger and a $30 transfer switch and you've duplicated an inverter/charger for half the price.

The Reongy inverter/charger you chose is actually a pretty good product. If you're going to use an inverter/charger, that is not a bad choice at all.

Are the tanks in the same room? Or in close proximity? Personally, if possible I would return the second inverter/charger and just run one with one battery bank. There will be less to wire and you'd save money on the inverter. Even if you run your heaters on the inverter, 2000W is likely sufficient (unless you have a thousand watts worth of pumps, which is unlikely). You could have one inverter with a big battery bank powering both aquariums.

In terms of batteries, I prefer AGMs because they're sealed and have pretty good depth of discharge, as well as generally long shelf life. 100Ah AGMs are a pretty decent compromise in terms of capacity and size. You could buy a few of them and tie the batteries together to form a high-capacity 12VDC power source. Wiring battery banks is a little more complicated than just hooking them together though. Be sure to do some research on the best way to wire lead acid battery banks if you're going this route. Regular flooded deep cycle batteries certainly work, just be aware that they will release hydrogen gas when charging. You need proper ventilation if you're not buying a sealed lead acid battery.

 

[chipmunkofdoom2]

Thanks for the invite! And this is a nice little system you have come up with, I love how it is both safe and reliable. Great job! I know you said you test in monthly, any thoughts on adding a push button, momentary, normally closed, in line with the relay coil to make testing easier?

Thanks that means a lot coming from R2R's resident electrician!

I haven't thought about that. I typically just unplug the utility power cable and make sure it fails over to the inverter properly. But, I suppose it wouldn't be too tough to wire in a momentary switch. Would you wire the switch to interrupt the mains AC flow entirely? Or would you just wire the switch to interrupt the AC going to the coil? They both should accomplish the same thing (de-energize the coil, which connects NC and COM), but switching just AC to coil will likely be switching much less current.

 

[Brew12]

Thanks that means a lot coming from R2R's resident electrician!

I haven't thought about that. I typically just unplug the utility power cable and make sure it fails over to the inverter properly. But, I suppose it wouldn't be too tough to wire in a momentary switch. Would you wire the switch to interrupt the mains AC flow entirely? Or would you just wire the switch to interrupt the AC going to the coil? They both should accomplish the same thing (de-energize the coil, which connects NC and COM), but switching just AC to coil will likely be switching much less current.

I would just de-energize the coil. It's much safer to do that than interrupting the main AC and for the purposes of what you are testing, it works the same.

 

[Finatik]

@Finatik @Brew12 is spot on. It's not that particular inverter/charger that I don't like. I'm just not a huge fan of inverter/chargers because they package everything into one device (charger, inverter, and transfer switch). If any one of those parts breaks, then the inverter/charger is toast. Unless you have a really good warranty. In a complete DIY system, if your charger fails, you can get almost any smart charger designed for your batteries. If the transfer switch fails, just get a new one. If the inverter fails, any inverter with similar power rating will do. As Brew12 also pointed out, the way that these devices charge the batteries is usually an unknown (they likely just float to 13.2 - 13.6VDC or so). I personally prefer to have a multi-stage smart charge as opposed to just floating the batteries to a set voltage. A quality AGM battery will last you up to 10 years if you don't cycle it too hard and avoid sulfation, which a quality smart charger will do. Lastly, a DIY system tends to be cheaper. A 2,000W PSW inverter alone will run you around $200 - $400, depending on the brand. Add a $30 battery charger and a $30 transfer switch and you've duplicated an inverter/charger for half the price.

The Reongy inverter/charger you chose is actually a pretty good product. If you're going to use an inverter/charger, that is not a bad choice at all.

Are the tanks in the same room? Or in close proximity? Personally, if possible I would return the second inverter/charger and just run one with one battery bank. There will be less to wire and you'd save money on the inverter. Even if you run your heaters on the inverter, 2000W is likely sufficient (unless you have a thousand watts worth of pumps, which is unlikely). You could have one inverter with a big battery bank powering both aquariums.

In terms of batteries, I prefer AGMs because they're sealed and have pretty good depth of discharge, as well as generally long shelf life. 100Ah AGMs are a pretty decent compromise in terms of capacity and size. You could buy a few of them and tie the batteries together to form a high-capacity 12VDC power source. Wiring battery banks is a little more complicated than just hooking them together though. Be sure to do some research on the best way to wire lead acid battery banks if you're going this route. Regular flooded deep cycle batteries certainly work, just be aware that they will release hydrogen gas when charging. You need proper ventilation if you're not buying a sealed lead acid battery.

@chipmunkofdoom2 Yes ... The tanks are in the same room. I live in a 2BR apartment and this particular apt unit came with an extra room they call a "den" but it has no windows or ventilation of any kind other than the heat and A/C vents in the ceiling. So I chose to make this my "fish room".

I chose this particular Inverter "because" it was an all-in-one unit and I was trying to cut down on having so many separate pieces of equipment to buy, arrange, monitor and keep up with in this one room. The tanks themselves have enough separate pieces of equipment !!! (smile).

So I'll have the two 120G display tanks in there (which both have 24G refugiums) along with a 40B and 20L for QT. All of that plus these two Inverters will make for a pretty full room, which I imagine is going to generate quite a lot of heat. To be safe, I'll probably have an electrician do the wiring for me. Electronic wiring is not my forte at all - and it will be worth the cost to ensure that I don't end up with something that could be a fire hazard.

 

[Blue Spot Octopus]

Thank you thank you for this thread.

 

[doughboy]

Amazon has a 5amp smart charger on lightning deal sale for $16.99 for the next 5 hours. I just ordered one.

INTEY 6v/12v 5A Smart Battery Charger, Portable Trickle Battery Charger for Vehicle, Truck, Motorcycle, Tractor and Boat

https://www.amazon.com/dp/B074875MTK/ref=cm_sw_r_cp_api_i_wdUeBbA7FVCQG

 

[doughboy]

Got the charger, Amazon Prime Sunday delivery. The fan is on while charging and is quite noisy. I’ll see if it turns off while trickle charging.

It’s charging a 35ah battery I got from harbor freight with 25% off coupon on Memorial Day for $57 with tax.

 

[doughboy]

Testing my battery backup setup.

Battery is connected to a low battery alarm protection module then to a DC-DC step up booster to get 24v out to power my DC return pump and power head.

The low battery protection module will disconnect when battery voltage is low and sound an alarm buzzer. The low voltage trigger is variable and I set it to 11.7v for this test.

The DC-DC booster keeps the output at constant 24v. I tested it on input from 11v to 13.8v and output is always 24v. This is important to keep the return pump running at set speed so as not to affect the Herbie drain flow.

I will be hooking up the 5amp smart charger directly to the battery so it will be used as my power supply to the pump when battery is charged.

No transfer switch or inverter needed for this setup. I do have to unplug the DC jack to turn off the pumps though. I did get a 24v relay module to use as transfer switch in case I need to power the pumps separate from the smart charger.

 

[chipmunkofdoom2]

@doughboy what kind of pumps do you have? Are they Ecotechs? If so, you actually don't need the 12VDC to 24VDC step up converter. The battery backup jack on Ecotech powerheads is designed to accept 12VDC straight from a lead acid battery.

No transfer switch or inverter needed for this setup. I do have to unplug the DC jack to turn off the pumps though.

True, but as a reminder to those out there who may be considering a similar setup, you do need DC-powered pumps for this to work. Many reefers have DC pumps now, but not everyone does. The DC pumps must also have a battery backup input, or you will still have to wire your own transfer switch to fail over to battery power when the power goes out. I know that Ecotech pumps have a battery input, but not all DC pumps do. You are correct though, a direct DC power source is the most efficient for DC pumps.

Out of curiosity, what did you mean by this statement?

I did get a 24v relay module to use as transfer switch in case I need to power the pumps separate from the smart charger.

 

[doughboy]

I am using jebao return and powerhead.
for powerhead, yes, running slower at 12v is fine and extends the backup time. That is how coral box battery backup works as well. But for return pump, I need to keep the rate constant, otherwise it will mess up the herbie drain flow. I may eventually configure to backup the powerhead only. I have to test running at 12v vs 24v to determine if I want to keep the step up converter.

If I did not use a transfer switch relay, then the smart charger is always in charge mode, as the pumps draw power from the charger. Not sure if that affects the battery long term, as battery I think is not in trickle charge mode while pumps are pulling power from the charger (charger yellow light is ON). If I have the relay, then the battery load is cut off, then I am sure the battery is on trickle charge mode at 13.8 v (charger green light is on). Do you think it will be fine with the smart charger connected to battery and powering the load? A car battery is usually not disconnected from the car when hooking up a charger, but that is usually not a long term setup.

 

[chipmunkofdoom2]

I am using jebao return and powerhead.
for powerhead, yes, running slower at 12v is fine and extends the backup time. That is how coral box battery backup works as well. But for return pump, I need to keep the rate constant, otherwise it will mess up the herbie drain flow. I may eventually configure to backup the powerhead only. I have to test running at 12v vs 24v to determine if I want to keep the step up converter.

If I did not use a transfer switch relay, then the smart charger is always in charge mode, as the pumps draw power from the charger. Not sure if that affects the battery long term, as battery I think is not in trickle charge mode while pumps are pulling power from the charger (charger yellow light is ON). If I have the relay, then the battery load is cut off, then I am sure the battery is on trickle charge mode at 13.8 v (charger green light is on). Do you think it will be fine with the smart charger connected to battery and powering the load? A car battery is usually not disconnected from the car when hooking up a charger, but that is usually not a long term setup.

I see what you mean. You're right, the Jebao has no battery backup port, so it's 24VDC or half speed at 12VDC.

It sounds like your system connects the Jebao pumps directly to the battery (through the 12VDC to 24VDC step up of course). The smart charger might be okay powering the load of the pumps. Basically, the charger is supposed to detect when the battery's voltage drops and step up the voltage/current to keep it charged. As the pumps run and drop the voltage, the charger should detect this and start supplying more current to the battery. But, it depends how the charger works. Smart chargers are generally (to the best of my knowledge) not designed to run a load, they're simply designed to charge a battery. By applying a load, you might trigger the charger to restart it's cycle, and the battery might be subjected to relatively high voltages (14.4 VDC or more) because of the way that most of these charge programs work.

What I would personally do (and what I'm planning to do for my Jebaos) is get a 24VDC DPDT relay. Take the Jebao power supply and wire it to the coil and to the normally open (NO) terminal. Take the battery output and wire it to the normally closed (NC) terminal. Then, take the output that goes to the pump and wire that to common (COM). When the power is on, the Jebao power supply will energize the coil. This will connect NO to COM, which means the Jebao power supply runs the pump. When the power fails, NC and COM are connected, which means the battery power flows to the pump. When the power comes back on, the coil energizes again and the power supply starts running the pump again. The battery is disconnected from the pumps and can charge without issue.

For a more simple system, you could just float the battery at a set voltage. Basically, you'd need to get an AC/DC power supply that outputs 13.6 VDC and connect that to the battery. When the power is on, the power supply will run the pumps. When power fails, the pumps will draw from the battery. When the power comes back on, the AC/DC power supply will charge the battery until it reaches 13.6V and supply the pumps with power. The downside is that I personally don't like just floating lead acid batteries. I feel like the batteries respond better when re-charged with a multi-stage charge. What I've learned about batteries suggests that floating leads to sulfation and stratification. But, it's an option.

 

[doughboy]

I tested using this relay with a similar connection to do the switcing
https://www.ebay.com/p/1-Channel-Is...AVR-DSP-Arm/1831460012?_trksid=p2047675.l2644

The low voltage protection module worked. It disconnected the load at 11v and sounded the alarm buzzer.
I am now test charging using the smartcharger with the pumps still connected.
Its a 5amp charger and the pumps take under 2 amps.

 

[doughboy]

for those looking to buy a battery, harborfreight has a 25% coupon on their website now good till 7/22.
The 35ah battery will cost $52.49+tax with coupon.
make sure to check the manufacture date sticker on the battery. It should be within the last few months, usually 2-4months, max 6 maybe.

 

[Ryanbrs]

This is just a way better option than a standard UPS. Wish more people had something like this on their systems.

 

[Reef-junky]

So with a car battery sitting not being used would it have changed once in a while? If so how often?

 

[Reef-junky]

I mean charged. Auto correct.

LOL

 

[bigaf84]

I'm going to build this before winter comes

 

[saltyfilmfolks]

Wow. Very nice work. @chipmunkofdoom2

You’ll forgive my impatience , I didn’t read the whole thread. I do have a question and perhaps it’s been covered and or you could point me I the right direction or the post if you remeber it.

I’ve been noodling this a while.

Everything in my tank except the heater is dc. It really doesn’t make sense to run an inverter. I should be able to use the same tender to charge , but run either 12 or , 24 volt by using an additional 12v battery or a buck puck, and run a 24dc line to the tank.
It seems too easy, seems like I need a switch in there. When the power is cut the draw is then only from the Battery automatically, but.
Or use a charger of higher amps than I’m using in the tank to make sure the battery gets topped up.
Additionally , I should Be able to connect a solar panel to it. Add a couple resistors and have cell phone and laptop charging.

It doesn’t really get cold in San Diego much , but I could use a smaller inverter if needed at the tank end. I’m a actualy more worried about losing power in the summer due to all the ac units.(my fans are dc too)

Any Thoughts or experience there O wise chipmunk of doom ?