The power went off at 2 am. The backup unfortunately only ran the two box filters for an hour. Then I added the battery operated air pump. The power came back on at seven. I was lucky every thing is okay. Next time I will try a low wattage power head. Maybe I will get more play time. I at least got an hour of life support.
Battery back up
- Thread starter Percula9
- Start date
BeanAnimal
Premium Member
We tried to tell ya 
But you were wrong that the pumps wouldn't run because that a true sine wave was required. The pumps ran without a problem, I just didn't have enough stored power. I did what I thought was best for what I could afford. I would say success was a mixed bag. I say more success because every thing survived. I appreciate everybody's help in this matter. We only learn by doing.
BeanAnimal
Premium Member
No, that is not what I said
I said: That means that it will not run motors well (if at all). If it is able to turn a motor, it will do so very inefficiently.
My statement was correct
A motor rotates through 360 degrees of motion based on the current and voltage available from a sine wave. The more the waveform deviates from a sinewave, the more inefficient the motor becomes. The more inefficient a load, the more battery power it wastes as HEAT (in the motor coil and/or output transistors of the inverter) instead of motion. Next time a sine wave inverter and a few automobile batteries would give you a much longer runtime. If things get rough, you can use the car to charge the batteries as you rotate them in and out of service during the outage. 1 or 2 large air pumps equipped with airstones can move an awful lot of water. For long outages, allowing the temperature to slowly drop is a good thing. Your livestock respires slower in colder water and will be much less stressed and use less oxygen.
We are glad to try and assist. Just be aware that sometimes you don't have to learn by doing. If you ask the question, others may have already learned and been able to pass along good information without the need for trial and error
dzhuo
Active member
BeanAnimal
Premium Member
No, the pumps ran less efficiently than they would of on the true sine wave provided by your house current
"Good enough" is a broad subject. Your goal is run time, not equipment protection. So in the future you want to choose a product that will help maximize the runtime. The marine battery with stand-alone inverter is not a great choice for cost vs runtime compared to a UPS targeted at computer usage.
The real world motor efficiency and operating parameters are 100% dependent on the the actual shape of the waveform and the physical properties of the motor. Your UPS was not designed to run motors, doing so is hard on the output transistors and driver. The effect is amplified as the battery voltage drops during discharge.
Furthermore, the better the ups, the better it will manage battery usage and inverter power. Battery battery management equates to longer runtime.
Just some food for though
I live in Louisiana and my power was out for 3 days last year when hurricane Gustav came through town. I have two battery powered air pumps that automatically come on when the power goes off. Those two pumps run on two D cell batteries. They ran for the full 3 days while my power was out and I didn't lose a single coral or fish. My tank is a 120 gallon reef with lots of mature SPS and LPS corals. Those little air pumps worked great and were very inexpensive. Cost me about $15 EACH. They don't move a lot of water but they keep the water oxygenated. Everyone should have at least one of these on their tank. I swear by them.
Stemonia what are the battery powered air pumps that you are talking about? A few weeks ago we had a bad storm come through and knocked out electricity from about 2am til 4pm the next day. I had a power inverter that I plugged into my cigarette lighter of my diesel pickup and ran an extension cord into my house and ran 2 power heads, one in my dt and one in the qt. It worked pretty well especially since my diesel truck idles very efficiently.
I got them from my LFS but here is a link to them on Marine Depot's website. There are two here to choose from. The ones I have are the Hagen air pumps.
http://www.marinedepot.com/ps_searchItem.aspx?SearchText=air pump&parsed=1
http://www.marinedepot.com/ps_searchItem.aspx?SearchText=air pump&parsed=1
