My successful setup for a long lasting backup power supply!

[Aszpara]

I had a really hard time trying to find a reliable long lasting backup power supply for my tank, other than a generator. If the power goes out, chances are I won't be home to maintain a generator so I did some research and spoke with my stepdad who is an electrician and this is what we came up with.

What we decided was the best route was to use a pure sine wave power inverter along with a deep cycle 12V battery. There are also modified sine wave inverters which are a little less expensive but I've read that not all equipment will work with a that kind. To be safe, I purchased a pure sine inverter (see link below for what I bought).

I have yet to purchase the battery but I was able to hook my tank up with the power inverter to my stepdads deep cycle 12V battery (unfortunately I don't know more info about the battery) and ran it for about 18 hours with my 50W heater, chiller, aquaclear 20 filter and LED lights (for my fluval Edge 6 gallon). After the 18 hours, the battery was at about half so it probably would have lasted for a full 36 hours easily. If you don't have enough to purchase a battery right away, you could hook the inverter up to your car battery and just start your car every few hours to charge the battery.

Keep in mind that a heater or chiller won't be running full time (and only one at a time) and if you're using a backup power supply, you will want to run the minimum amount of equipment necessary. A battery operated pump would be beneficial during this time. I purchased one on amazon for $10 (see link 3 below).

You can purchase higher wattage power inverters but they'll cost a little more. My 300W inverter was about $100 but I suspect a 1000-2000W inverter wouldn't be more than $200. I think my stepdad said he paid about $100 for his battery.

Our plan is to eventually hook up the power through the inverter/battery combo and if the main power supply stops, the backup will automatically kick in. We're also planning to add a solar panel battery charger in my window to maintain the battery supply for longer periods without power (see link 2 below). The solar panel would only be helpful in areas that get a decent amount of sunlight. They're very affordable too, around $20-$25.

There really aren't any good options readily available for a good backup supply. I was really happy to find that I could put together a backup power supply that could last for over a day if needed. I'll update this thread once we make some progress with the power supply but until then, I'm happy to answer whatever questions I can! I'm still a newbie (started Jan 2015) and I've learned so many helpful things from this site so I was really excited to be able to contribute something of my own to the community. :bounce3:


Power inverter: $100-$200 (estimated)
12V deep cycle battery: $100 (estimated)
Solar panel battery charger: $20-$25

Link 1:
http://www.amazon.com/gp/product/B00...ilpage_o01_s00

Link 2:
http://www.amazon.com/gp/product/B00...=ATVPDKIKX0DER

Link 3:
http://www.amazon.com/Marina-11134-...44326679&sr=1-1&keywords=battery+powered+pump

 

[skeeter_ca]

That sounds like a great back up plan. One question, where is the battery going to stored? It needs to be in an area other than the house or garage. An outside shed would be optimal. When discharging and charging, lead-acid batteries can give off hydrogen gas which is poisonous and explosive. Be careful!

 

[Indymann99]

That sounds like a great back up plan. One question, where is the battery going to stored? It needs to be in an area other than the house or garage. An outside shed would be optimal. When discharging and charging, lead-acid batteries can give off hydrogen gas which is poisonous and explosive. Be careful!

Or just use a sealed battery like an Optima Blue Top
http://www.optimabatteries.com/en-u...d34m-bluetop-marine-boat-deep-cycle-starting/

 

[skeeter_ca]

You could but as far as can tell they don't come in deep cycle version, but I may be wrong. The advantage of a deep cycle over a standard battery is you can draw it down a lot further before it can damage the battery.

 

[Indymann99]

Blue top is deep cycle (or as close as it gets with Optima) - use them in my boat. They are very good.... not inexpensive... but good.

 

[skeeter_ca]

Ahh....ok

 

[CuzzA]

Aszpara,

Here is my tutorial on what I did. Post #19 give a detailed explanation of how the system works.

http://www.reefcentral.com/forums/showthread.php?t=2440002

 

[Aszpara]

That sounds like a great back up plan. One question, where is the battery going to stored? It needs to be in an area other than the house or garage. An outside shed would be optimal. When discharging and charging, lead-acid batteries can give off hydrogen gas which is poisonous and explosive. Be careful!

We don't have it set up right now but once the set up is complete, the battery will reside in the garage. My stepdad is very particular about things of this sort and he said that the battery would be fine in the garage since it does not give off much gas. I appreciate the heads up though!

 

[Aszpara]

Or just use a sealed battery like an Optima Blue Top
http://www.optimabatteries.com/en-u...d34m-bluetop-marine-boat-deep-cycle-starting/

Thanks for the suggestion! I was looking into getting a battery like this.

 

[Aszpara]

Aszpara,

Here is my tutorial on what I did. Post #19 give a detailed explanation of how the system works.

http://www.reefcentral.com/forums/showthread.php?t=2440002

Wow, what a great post! It sounds like you have a pretty similar set up to what I plan on doing. Thanks so much for sharing this with me! I really appreciate it! It will probably save me some trouble when I get mine fully set up!

 

[Rybren]

A few things for you to consider.

Links 1 and 2 are broken for me.

I don't know what solar charger you are looking at, but I can absolutely guarantee you that anything for $20-25 won't charge your battery. You will be lucky if you get 0.5A out of it and then only for a few hours when the sun is pointing directly at it. Your 12V Deep Cycle battery probably has at least 100Ah capacity. You need about 10% of the capacity to get any sort of decent charge into it, so that means that you'll need your solar system to put out a minimum of 10A. To get that, you'll need to spend a couple of hundred dollars on solar panels and then more $$ to get the solar charger.

In terms of the battery, what is its capacity and is it a true deep cycle or is it a marine/hybrid? If there is anything listed about CCA (cold cranking amps), then it is a hybrid battery and not a true deep cycle. A real deep cycle will have its capacity listed in Amp-Hours (Ah). The hybrid will still work, but it won't last as long, especially if you take it below 50% capacity very often.

Because you got 18 hours out of the battery and you think that it was down to 50% capacity, don't think that you'll get 36 hours out of it. It doesn't follow a linear line and will drop off rather quickly after 50%. Did you measure the specific gravity of the acid in the battery to determine that it was at 50%? That's the only way that you can tell.

Sorry if I sound like a downer, but I want to temper you expectations so you won't be disappointed later on.

I have two solar systems in place at my cabin. The first is very small and only charges a hybrid battery much like yours. The solar panels and charge controller (no inverter on this system) cost $200 and if I use the system a lot, it will take a couple of days to fully charge the battery (with no simultaneous use going on). This is because the solar panels are undersized for the capacity of the battery.

The other system charges a 24V 232Ah battery bank comprised of 4 6V True Deep Cycle batteries. I have 840W of solar panels, a high end Solar Charge Controller, and a good quality True Sine Wave inverter. Cost runs into the several thousands.

 

[Aszpara]

A few things for you to consider.

Links 1 and 2 are broken for me.

I don't know what solar charger you are looking at, but I can absolutely guarantee you that anything for $20-25 won't charge your battery. You will be lucky if you get 0.5A out of it and then only for a few hours when the sun is pointing directly at it. Your 12V Deep Cycle battery probably has at least 100Ah capacity. You need about 10% of the capacity to get any sort of decent charge into it, so that means that you'll need your solar system to put out a minimum of 10A. To get that, you'll need to spend a couple of hundred dollars on solar panels and then more $$ to get the solar charger.

In terms of the battery, what is its capacity and is it a true deep cycle or is it a marine/hybrid? If there is anything listed about CCA (cold cranking amps), then it is a hybrid battery and not a true deep cycle. A real deep cycle will have its capacity listed in Amp-Hours (Ah). The hybrid will still work, but it won't last as long, especially if you take it below 50% capacity very often.

Because you got 18 hours out of the battery and you think that it was down to 50% capacity, don't think that you'll get 36 hours out of it. It doesn't follow a linear line and will drop off rather quickly after 50%. Did you measure the specific gravity of the acid in the battery to determine that it was at 50%? That's the only way that you can tell.

Sorry if I sound like a downer, but I want to temper you expectations so you won't be disappointed later on.

I have two solar systems in place at my cabin. The first is very small and only charges a hybrid battery much like yours. The solar panels and charge controller (no inverter on this system) cost $200 and if I use the system a lot, it will take a couple of days to fully charge the battery (with no simultaneous use going on). This is because the solar panels are undersized for the capacity of the battery.

The other system charges a 24V 232Ah battery bank comprised of 4 6V True Deep Cycle batteries. I have 840W of solar panels, a high end Solar Charge Controller, and a good quality True Sine Wave inverter. Cost runs into the several thousands.

No worries on sounding like a downer, I appreciate the honest feedback. The solar charger would not be used to solely charge the battery. The battery would be fully charged when I need to use it and I'd use the solar charger to maintain the battery in the event of a power outage. It sounds like we'll have to do some reading up on them though to make sure the solar charger will be sufficient.

My stepdad has a voltage meter and that's what we were using to measure the life on the battery.

We haven't picked out a battery yet but I have read some information about them and was looking for a battery with amp hours listed.

I'll pass on the info to my stepdad and I'm sure it will be helpful when we start buying things to put the system together. Thanks!!

 

[Rybren]

You're welcome. Measuring battery Voltage will at best, only be somewhat accurate and ONLY IF the battery has been at rest with no charging or discharging for 3+ hours. Measuring Specific Gravity is the way to go. You can pick up a tester at an auto parts place for $5-6.

Here's a voltage v State of charge graph for you.

And here's a Specific Gravity v State of Charge table. Note that the SoC v SG changes depending on the temp.

 

[Bakerman]

Nothing at all wrong with your approach, any "ups" is, in the simplest terms, just a battery charger (controlled rectifier), a battery, and an inverter.

Solar panel is a good idea if you can justify the cost, but you may also consider simply using an appropriately sized battery charger off of AC to continuously charge the battery. That way, you can leave all of your equipment running on the battery/ups 100% of the time. When the AC goes out, the battery simply stops charging. No need to have any circuitry to swap the power from mains over to the battery system.

Ups and downs to this. Efficiency is one. Conversion of AC to DC and vice versa isn't without loss, and can be significant. So your 300 watt system on ac would take, oh, 400+ to run through an per sine wave inverter w/ battery charger all of the time. But 100 watts isn't much, and it can be expensive to construct a proper failover circuit.