Battery Backup?

[thesoulpatch]

I need a good one that could run the heater and a wavemaker or pump. Ideas? Prefer something small enough won't take a bunch of room up, but still last awhile.

Thanks.

 

[mcdrichj]

Do you know the wattage of everything combined and how long you want the backup to last?

 

[BZOFIQ]

Since you said you need heater included the Honda EU2200i would seem like the option. No battery based backup is going to last with a heater. Generally, with battery backup you're only backing up the flow.

 

[Dom]

I have 3 deep cycle marine batteries connected to a 5000 watt inverter. There is also a charger and an auto-transfer switch.

I get 36-48 hours out of it, depending on how much the heater comes on. After that, I have a Honda 3000is.

Typically, I leave the battery backup to support the tank overnight. I bring out the generator to run things and recharge the battery backup during the day.

 

[thesoulpatch]

Ah okay, I gotcha then.

Can't have a generator since I'm in an apartment. I'd get some sort of fine i'm sure.

 

[mcdrichj]

If you dont know the average wattage of everything you want on a battery backup them get a kill-a-watt or something similar and plug whatever you want to run into it and get the average hourly wattage that you use however this is highly dependent on the ambient temperature in the room since you want to use a heater. Anything is possible like @Dom has shown with their setup. You just need know know how much electricity (watts) and how much time you want to have a backup for.

 

[BZOFIQ]

I have 3 deep cycle marine batteries connected to a 5000 watt inverter. There is also a charger and an auto-transfer switch.

I get 36-48 hours out of it, depending on how much the heater comes on. After that, I have a Honda 3000is.

Typically, I leave the battery backup to support the tank overnight. I bring out the generator to run things and recharge the battery backup during the day.

Dom,

Do you have any pics of your setup? What are your heaters rated at? I'm very surprised you'd get that much run time off battery with heaters on.
I am planning to retrofit one of my APC SMTs with 2 x Deep Cycle batts I bought recently but I don't think I'd get anywhere the runtime you're quoting.

 

[thesoulpatch]

@mcdrichj Yeah, I don't know off the top of my head I have to look at everything when I get home, but the heater it self is 150w and then I have the nero 5

 

[mcdrichj]

Yeah but the heater in general wouldnt be on 100% of the time unless its too small and you are just under temp.

 

[braappn]

Hi haven't posted in a long time but logged in to give some input here. I researched this heavily when designing my tank.

Your easiest and probably cheapest option will be something like the Ecotech or Coralbox battery backups for their powerheads.

The more expensive and intricate option that takes up much more space will be deep cycle batteries combined with an automatic inverter/charger.

I went with the Tripp-Lite UT750UL inverter/charger and a single 200ah deep cycle agm battery. This is like an $800 setup. More batteries paralleled together will provide more run time accordingly. The size of the battery bank and therefore run time is limited only by space and money.

Run time is actually pretty simple to calculate. Convert the watts your equipment draws at 110 volts into amps at 12 volts. Factor in the inefficiency of the inverter of something like 20%. Then compare this to the amp hour rating of your battery bank. Google it for a better explanation.

My system powers my return pump. My sump is large relative to my display so I figured keeping this water volume tied in would help slow the temperature drop. I also have a small 50w heater connected to this setup. The heater is set to a lower temp than my usual tank temp, somewhere around 74 degrees. It is only meant to be a last-ditch effort to slow the rate of temperature drop before the temp gets truly critical.

I set it up this way to balance battery run time vs. tank survival. I can't remember my math exactly but I estimated it would run around 20 hours total with the heater kicking on for the last 8 hours. Power outages lasting longer than this are very rare in my area.

Another thing to consider is insulating your tank in any way possible to reduce temperature drop during a power outage. I have blue foam boards insulating my entire sump as well as the back and bottom of my display. It's cold where I live.

Also note it is not wise to run flooded lead acid batteries indoors in your home. They emit hydrogen gas when charging, and carry the risk of leaking. AGM batteries (more expensive) are much more appropriate indoors.

If you use an automatic inverter/charger, make sure the circuit it is plugged in to can handle the additional draw of the charger kicking on when the power comes back on.

For $800 I got piece of mind that my tank will be ok if I am away during an average short power outage. Longer than that and I would need more batteries. This is really just meant for when I am away. I also have a generator I can manually hook up if I am around.

I hope this rambling helps!

 

[mcdrichj]

The calculations P=I*V >>>> I=P/V

P is the power in watts, I is the current in amps, V is the voltage. You can take your wattage and divide by 0.8 to account for the 20% power of the inverter. Generally batteries are measured in amp*hours. Say you have a battery that is 12 volt, 200 Amp*hour and your power draw is 50 watts.

Compensate for inverter inefficiency 50/0.8=62.5 >>> Calculate Amps 62.5/12=5.2 >>> Calculate time in hours 200/5.2=38.46

Most likely you will use more than 50 watts but this is an example to help you with the calculations.