# Battery Backup for the Planted Aquarium



## magicmagni (Aug 19, 2004)

With all the power outages and brown outs lately I decided that something needed to be done. My fish were stressing out from the lights flashing on and off, the temp drops and I was getting frustrated with the filter that kept loosing suction. I have enjoyed using a uninterrupted power supply on my computer and wondered if one would work on my 55 gallon aquarium. I checked out www.APC.com and found that they had something that would handle the electricity my tank needs, but the backup time was nothing- under 5 mins. I looked at other options that would last longer, but they were over $1000 so I decided to go the DIY route. I figured a way to hook a larger battery to the unit and extend the runtime. Heres how I did it.

I scored a APC UPS from office depot for only $20!!








It can backup around 300 watts and came with a power strip and a USB cable (if you want to hook up to a computer to monitor it.) It also has surge protection (on a grounded outlet) It features an audible and visual indicator to show when it's working and will beep faster and faster as battery voltage decreases.

The battery that comes with it is quite small and is designed to fit inside the unit. For my application I decided not to use the original battery (now it's a paperweight) For this tank we need power and I got a lot of it. I used a marine battery from a local automotive place that I got for around $40 bucks and for a little extra I got a plastic container that it fits it. This is to be used externally of the UPS unit. Here's what I got.









In addition to the battery and the APC UPS unit I needed a little bit of hardware- all under $10
- 4' 12 gage insulated wire
- 2 male spade crimp on connectors
- 2 eyelet crimp on connectors
- 1 pack heat shrink

Here's how it went together:

I went ahead and made 2 2' leads that would go from the APC UPS unit and the battery terminals. I went ahead and crimped on an eyelet connector on one end for the battery side and a male spade connector on the unit side that hooks up to the female spade connectors on the unit. These connections were found inside the units battery compartment. They would normally be connected to the original 12V battery then fits inside. I went ahead a heat shrank the connectors to clean it up a bit and to help discourage shorts. Here is a pic of the connections to the unit. I just connected positives and negatives and that was it. There was no need to insulate the negative, but I went ahead and shrank over the spades to help make sure they stayed together and also to discourage shorting to ground.









To make for a better and safer install I wanted to put the cover back on the battery compartment. To make it fit a used a dremmel tool to notch out a place for the wires to fit through. I also used a zip tied the wires on each end of the notch to act as "stoppers." This will take stress off the terminations inside the battery compartment that was made.









Here is what the finished product looks like. Its really quite simple. Really all that I've done it replace the little 12V battery that is included with a much larger 12V battery so that there is a reasonable runtime.









Hooking it up to a load:

I had to be careful what I hooked up. I had to stay around 300 watts. Much over that and the unit would sense an overload and shut down. I realized that my tank consumes 630 watts so it was time to go on a diet. I decided to separate the hardware in two categories: UPS powered and non-ups powered.

I recommend hooking up the bare essentials only to the ups. This will give the longest run times and not over load the unit. I decided that the battery would run the following items:

-heater 150watts
-1 bank of lights 130watts
-filter 35watts
-ph probe 2 watts (well not needed, but for 2 watts why not?)

This gave me a total of 317 watts. A bit over my goal, but then again the heater is usually only on in short bursts.... crosses fingers.

The rest of the Items that were not run through the UPS:

-2nd heater 100watts
-2nd bank of lights 130watts
-substrate heater 80watts
-air pump 2.5 watts

I hooked up 2 power strips under my tank in the cabinet. One strip would be powered by the UPS and the other directly to the wall outlet. I hooked them close together so that I can easily change what gets and what doesn't get backup power simply by plugging and unplugging the item from is respective outlet.









The results:

I went ahead and unplugged the tank. As soon as I did the backup power came on seamlessly. The unit indicated with a little light on the front that it was running on backup. It also sounds an alarm every 30seconds. As the power gets lower the alarm sounds more and more frequently until the unit shuts off. I left my tank unplugged for an hour and it ran fine the whole time, but then I chickened out and plugged it back in. The battery was still at least 3/4 full so it probably would have gone hours.


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## dennis (Mar 1, 2004)

Magic,

Thats genius indeed There are a couple things that might be done to improve the runtime. If this was a serious problem for someone, (I believe places, like Singapore and parts of India often have rooling blackouts every day or so) they could invest in a heavier duty gel style battery and I am sure that a recharging unit could be attached to the battery and connected to the main power supply that wold keep it charged to full capacity when the power is on. One could also just take it back to the auto parts store when it needs recharging. You could also leave the heater off of the backup except for times when it would be absolutely necessary. Even a poorly insulated house in the dead of winter should not get to cold for a day. The tank should stay a few degrees warmer than the room temp, especially with 130 watts of light over it. Just a thought. Brilliant idea again


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## magicmagni (Aug 19, 2004)

Thanks for the reply. Rolling blackouts..... I thought that only happened in California LOL. I'm hoping that the UPS unit can recharge the battery-although it may take a while! I put the amp meter on it after an hour usage and there was current flow, but only about 500mA. Checked it again 6 hours later and it's decreased to 50mA so it is still charging, but almost there. Time will tell.


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## dennis (Mar 1, 2004)

I did not realize the UPS unit would charge up the battery, never thought of that. If so you should be fine Once again, great thread!


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## Piscesgirl (Feb 25, 2004)

That is ingenius indeed! Although I am developmentally disabled when it comes to doing things like that 

As for a poorly insulated house not getting very cold in one day in winter, that may be so - but a mobile home even in Spring and Fall can get extremely cold in just a few hours (or extremely HOT). In our ice storm two winters ago, I lost many fish to the cold - only saving some by running them to the office in buckets (luckily my office is in a hospital and power goes to hospitals first). Most luckily I was able to drive as the streets melted much earlier than anything else although the power lines, etc. were down and most were without power for three (the luckiest) to seven or more days (some folks I knew were out of power for fourteen days). And, my phone company (Sprint) kept getting their generators stolen, so my phone kept going off. 

I need someone to come make one of those things for me


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## Sir_BlackhOle (Jan 25, 2004)

Excellent work! I had thought about using a UPS also, but decided it was too expensive. This is a great alternative!


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## magicmagni (Aug 19, 2004)

I'm glad you all like my idea. Like you Sir_BlackhOle I had written it off because of price, but when I saw these UPS getting closed out for $20 I figured why not give it a go. Heck I had the battery already which was left over from another project. At first I actually tried to use my existing Back-ups 800 that is on my computer because it can backup more watts- (like 600), but it wouldn't work because it's made for a 24V battery. Using that would have meant buying another 12V battery and hooking the two in series. This would have made for an even longer lasting and higher capacity setup, but I decided it would be overkill for my tank.... now for a 100 gallon+ this is a possibility or perhaps necessity.

Piscesgirl: That's terrible that you lost your power for so long. I think the longest we ever lost our power here is for 2 days a couple winters ago. Fortunately we are very close to the power station so we tend to get the power back sooner than others. I don't know what your situation is, but many people these days use portable generators. They have them about the size of a lawn mower and run on gasoline. I've seen people use them when they go camping. I don't know what they cost, but maybe something to look into.


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## Piscesgirl (Feb 25, 2004)

I thought about generators, but they go 'missing' out here, and I don't have a garage or shed to store it in. I've thought about chaining it to my fence (I chain the lawnmower). 

People are very creative theives out here -- one person even ran a lawnmower apparently (to replicate the sound) and stole the generator while the owner was still in the house (asleep).


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## gpodio (Feb 4, 2004)

Have you run the battery flat and recharged it with this unit? This would be a god test to do. The charging circuit in this UPS is made to charge a 7AH battery and will therefore deliver no more than 1.75A (21W) charge load (the battery's maximum charging load). When the battery reaches the charging load, no more charging occurs to avoid overcharging the original battery. Although I have not modified this particular model, other APC UPS units that I have modified to use car batteries were not capable of delivering more current on the charging circuit than the factory setting. I therefore had to use a separate charger to charge the battery, usually a 10A or 20A charger. The easiest is to connect a regular automotive trickle or deep cycle charger to the battery however I have always removed the original charging circuit from the UPS unit as I think it could be damaged by the additional charger. Alternatively you could place some diodes on the charging circuits to stop the stronger one from potentially damaging the weaker one, but it's more work than cutting two leads and there is really no use in doing this unless you want the ability to place the original battery back in the unit at any time and take it on the road with you.

Still, charging both batteries to 21W, the car battery should last longer, but you could get much more out of it if you were to charge it to it's full capacity.

Hope that helps
Giancarlo Podio


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## anonapersona (Mar 11, 2004)

*temp and insulation*

I am fearing a winter power outage and so have added insulating board to the back of each of my tanks, as well as thin foam sheeting against the glass under the tanks. I used the white board that has a nice blue plastic side, looks like blue vinyl but with a bubbly effect. Just insulating a side or two will slow that temp drop considerably.


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## magicmagni (Aug 19, 2004)

Wow,

Forgot about this thread. Well my setup is still in operation and has survive several short power outages and brownouts, longest one being 3 hours.

gpodio:

Thanks for the info. So you've tried this before? Good to know someone else who has messed with this stuff. I've alway been a little uncertain about the ability of the charger to fully charge the battery, but thinking about it I think I'll work OK, but I'll have to test this out and see how long it'll go. I'm not an electrical engineer or anything, but I have taken a few electronics classes in college. If I remember right when voltage (force) is applied to a battery, the electrons will flow from the source (the charger) to the battery as long as there is less voltage in the battery. This will continue until the voltage in the battery is the same as the charger- they reach an equalization. (in this case it's 12V- if I remember correctly) The amperage or current flow is just how many electrons can get from point A to point B in a given time. High amperage is like draining your tank with a 4" hose compared to low amperage which would be like draining it with a straw. One allows more water to pass at one time then the other, but the speed (force) in which the water travels through the pipe (voltage) is the same. I think that my application is more like the straw analogy. It will take a long time to recharge, but will get there eventually (this is actually better for the battery). That said most automotive charging systems are around 14V not 12V so in reality a "12V" battery really holds about 14V. This fact may indeed hinder the runtime of my setup somewhat as the highest the UPS will charge the battery is 12V. So it doesn't last as long... so what? I suppose that if one wanted to optimize the run time they could do what you suggest and hook up a car battery charger, but I don't know if it would be worth the gain. Maybe get you an extra hour?? I don't know.


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## zeek (Jan 5, 2005)

magicmagni said:


> So it doesn't last as long... so what? I suppose that if one wanted to optimize the run time they could do what you suggest and hook up a car battery charger, but I don't know if it would be worth the gain. Maybe get you an extra hour?? I don't know.


From what I understand you tested this and got an HOUR of backup time before you gave up and applied power. This is phenomal considering you are backing up the lights!
I would not worry about the extra 2v to get the full 14v, because you have to consider the long-term cost of the electricity to power the extra charger. All the power we consume with our aquaria already places a significant burden on the electric bill, so I am watchful of this drain. Besides, when my power fails it's usually only a flicker or brownout. Never (knock on wood) has it been off for more than an hour, so I wouldn't have a need for the additional time the 2v would provide.

kudos for a great DIY tip! My UPS, same model as yours I think, only provides backup for the filters. Lights would be ideal...

zeek


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## gpodio (Feb 4, 2004)

Wow it has been a while!

Yes I use a similar method to power telescopes during field trips. There are several ways to charge a battery, each with their own advantages. Ideally one should find out exactly what is in your individual UPS unit to see if it would be wise changing it with something better or not. Charging can occur at a fixed voltage/variable current or the other way around which is the more common/cheaper method. A car battery is usually charged at 13.8 volts with little to no current control in order to get the fastest charge possible (newer cars may have more complex charging systems by now). A constant voltage, "taper" charger with current limiter is probably the best suited for such a role as this will keep a battery at full charge wihtout any damage even for long periods. Non current limiting charges work well to quickly charge a battery however they are not a good thing to use to maintain the battery charged. Considering we really don't need fast charging, more important is complete charging and good condition of the battery itself, a constant voltage charger with current limiting would likely be best. Most trickle chargers use similar charging circuits, while fast charges are different.

It really depends on how long of an outage you plan for. It's obvious the better the charge the longer it will run for and the better charger will also guarantee the battery is in good shape when it's needed. 

A simple setup I use for one telescope is:

Trickle charger => Car battery => power inverter (12VDC > 110VAC)

This is a good backup device to keep in the garage in case you need it during a long power outages or emergencies. It does not however have the circuit to provide 110V continuously without draining the battery, that is the useful circuitry from the UPS unit. We also use the inverters connected to our cars when the batteries run out, I guess if you have the spare gas the car can be used as a last resort for longer outages 

Giancarlo Podio


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## magicmagni (Aug 19, 2004)

gpodio:
Yeah, I'm not expecting a quick recharge so I think that the charging system on the UPS is adequate. That sounds like a good setup you have on your telescopes. I use a similar setup to power my laptop computer and stuff when I'm in the field and when in a bind it has served as a tank backup as well. Never though of using the car to power the tank in a bind, but hey it sure beats buying a generator!!! 

I've really havn't messed with this since I set it up, but probably this weekend I hope to "run it to the ground" I'll unplug the tank and see how long it goes documenting the voltage drop over time. It did backup for maybe 3 hours last power outage, but this was actually at night when the lights were off so it will be interesting to see how long it can go with the full load and then how long it takes to recover. For those interested I hope to document my findings here.


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## Sir_BlackhOle (Jan 25, 2004)

Looking forward to it!


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## gpodio (Feb 4, 2004)

magicmagni said:


> gpodio:
> Yeah, I'm not expecting a quick recharge so I think that the charging system on the UPS is adequate. That sounds like a good setup you have on your telescopes. I use a similar setup to power my laptop computer and stuff when I'm in the field and when in a bind it has served as a tank backup as well. Never though of using the car to power the tank in a bind, but hey it sure beats buying a generator!!!


They both run on gas so not much difference right? 



> I've really havn't messed with this since I set it up, but probably this weekend I hope to "run it to the ground" I'll unplug the tank and see how long it goes documenting the voltage drop over time. It did backup for maybe 3 hours last power outage, but this was actually at night when the lights were off so it will be interesting to see how long it can go with the full load and then how long it takes to recover. For those interested I hope to document my findings here.


I look forward to it too.

Giancarlo


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## mrmagnan (Jan 29, 2005)

magicmagni said:


> gpodio:
> Yeah, I'm not expecting a quick recharge so I think that the charging system on the UPS is adequate.


This is not good for the long term health of batteries. They need a significant amperage "bulk charge" to remove impurities and deposits on the battery plates. The low amperage will take forever to charge and will never dislodge impurities. I would go with the trickle charger after a power outage to maintain the health of your battery. This could mean the difference between a battery lasting a year or two or 10-25 years and will keep its capacity at th e maximum.



magicmagni said:


> gpodio:
> I've really havn't messed with this since I set it up, but probably this weekend I hope to "run it to the ground" I'll unplug the tank and see how long it goes documenting the voltage drop over time.


I would not recommend this on repeated occaisions. Most batteries should be kept withing 40-60% Depth of Discharge (DOD) to prevent damage to the plates.

If you want to calculate your healthy backup time, do the following:

1) Calculate your backup electrical load by adding up all the amps of continuous electrical components (lights, pumps, etc). Amps = Watts / Voltage

2) For a heater, which is non-continuous, determine what percentage of time it runs (remember your room will drop in temperature, so your heater will run more). Multiply this percentage to the amperage calculation in #1.

3) Total amps from step 1+2

4) You now have your load.

5) Find out how many Amp hours (AH) your battery is rated for. It may be expressed in "reserve minutes" for something like an RV battery. Consult the specs of your battery on the manufacturers website or phone and ask them the AH rating. While your at it ask them the recommended DOD for long term performance.

6) Take your AH rating and multiply by DOD. This will be your usable amps.

7) Divide your AH by the Load amps and........... that is how many hours backup you have. Keep in mind you can discharge deeper if the power outage is extra long. I would simply turn of some/all of your lights. Plants will survive without light for a while.

An example.

1) Continuous load = 220W / 110VAC = 2 amps
2) Non-continuous load = 330W /110VAC * (0.33) = 1 amp
3/4) Total load = 3 amps
5) Battery is 175 AH
6)175 AH * %50 DOD = 87.5 usable AmpHours (backup)
7) 87.5 AmpHours / 3 Amps = 29 Hours

Michael


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## mrmagnan (Jan 29, 2005)

*Industrial UPS setup*

I will outline how I would do this if I had a fish room or large tank and was concerned about outages.

1) Setup a 12VDC or 24VDC battery system using car batteries or sealed gel batteries (VRLA). Note. Car batteries are used for providing a quick burst of power and then the voltage drops very quickly. Not the best backup source because a car battery only has to start a car, not keep it running. I think an 12VDC RV battery would be very economical. See my previous reply/post on sizing battery systems.

2) Purchase an inverter sized to accomodate all the loads you are concerned about + 10-15%. I will let you decide what that is. Ask yourself, "are my lights that important?" because inverter watts cost money. If there are no electronics on your backup system, save more money by purchasing a modified sine wave inverter over a pure sine wave inverter. Computer UPS's are expensive because they are pure-sine inverters, which are crucial to electronics and circuits. Lights, pumps, heaters don't need pure sine unless they are very sophisticated and have chips. RV shops, renewable energy companies & online suppliers/manufacturers are all great if you shop around. Don't buy the best because it is just for backup after all. Analytic Systems in BC, Canada might sell direct to you if you're nice to them.

3) Purchase an Automatic Transfer Switch (ATS) which can sense when your grid power fails. It will then switch your AC loads to your secondary power supply (the inverter-battery system). These are used extensively in the backup power industry, and is a critical component of a UPS if you want it to work remotely. If you can simply change it over yourself, skip the ATS and simply plug everything into the inverter when the power goes down.

4) After a power outage, use your car trickle charger and charge it up. If it is a different voltage than the UPS battery bank (ie. 12 VDC vs 24VDC), you may have to hook up your UPS batteries in parallel rather than series to allow a charge. Charging is best done in ventilated areas...

Everything is very easy to set up. The only thing that may require some decent knowledge is the UPS as it is connected to your grid power (zap ouch).

PLEASE REMEMBER THAT A BATTERY BANK IS CAPABLE OF HURTING YOU. IF YOU ARE UNCOMFORTABLE WITH THIS STUFF, FIND SOMEONE WHO IS. IF YOU DON'T KNOW WHAT AN INSULATED TOOL IS, FIND OUT OR MOVE ON.

Enjoy.

Michael "Wind Turbine" Magnan


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## magicmagni (Aug 19, 2004)

Sorry about the delay. It seems that it's been difficult these days to get a connection to the APC site?? Server problems and such??

mrmagnan:

Thanks for all the info. The system you describe is also quite viable. I just used what I had on hand. The battery I am using is a "deep cycle" battery that I used to use on my fishing boat. I would have liked to get my hands on the sealed gel cells I use on the equipment at work, but that's another story. There are definitely better ways to do it than the way I did, but hey it works.

As far as calculating run time. I am familiar with what you're saying and that's a good way to do it too, but sometimes I like to do what I call a "reality check" and test it out for real, in this case I'm glad I did and probably should have run this test sooner considering the results.

As far as the battery health I was always under the impression that the best way to charge a lead acid battery was with a trickle charge- at low current?

Anyways here are the results of my test:

DIY Battery Backup test (405W max load)
Battery condition-full charge (green) 13.58 VDC
3:30pm disconnect main power 12.76 VDC
4:00pm 12.14v (grn)
4:30pm 11.95v (grn)
5:00pm 11.82v (grn)
5:30pm 11.81 (grn) 250w Heater on
6:00pm 11.59v
6:30pm 11.5v

So it got 3 hours backing up around 400Watts. A nice feature of this battery is that is has a built in hydrometer that tells you the batteries charge; however it stayed green though the whole test meaning the battery never dropped below 60% before the UPS sensed low voltage and shut down. Now here is where it got exciting. Remember when I said that this was rated for 300W? Well I didn't realize that the wrong heater was plugged into it so instead of the 100W heater I had the 250W plugged into it. At around 6:00pm I came in the room and I smelled something burning up a little. I didn't think anything of it yet, but by the end of the test there was no mistaking that it was the UPS!! The plastic on the bottom got so hot is started to melt!! Obviously when it says 300W they mean it!! I have since erred on the side of caution and give it 20-30W headroom so it doesn't heat up as much.

Well it's working fine still, so I didn't break anything internally, but now I am sure glad I did this test. Talk about a fire hazard. This is why I have to stress that anytime you take something a modify it you need to be careful!!

I checked the battery a couple of days later and the battery was back up to it's full charge. So anyways I am quite pleased with the results. The backup time is better then nothing and mainly will prevent the lighting from going on and off and the filters getting stuck and stuff. It is definitely one less thing to worry about during a short outage and buys me time to take action during a long outage. 

I havn't had much time so I have disconnected it for now, but hope to get it back on and do another full load test, but this time pay close attention to the heating issue. If it gets too hot still I may have to scrap this whole idea :-( or get a bigger UPS or look into mrmagnan method). I think however that it should be OK as long as I keep the watts under the 300W mark or a little lower, which is how it is set up to run now when it gets hooked up.

Jeff


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## mrmagnan (Jan 29, 2005)

Trickle charges are fine but they won't remove the buildup of sulphates on the lead plates.

Once a year you should drain them completely and give them a good bulk charge at higher amperage than is normal.

This will for the plates to shake off any impurities due to the high level of excitation. Call it a battery party.


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