Emergency Water Circulation

[justDIY]

Ok, here is the heart of my e-water project.

It is an attwood V750 submerisble bilge pump, 750 GPH at 0 head.

I bought mine from Sporting Goods dept at Wal Mart, $17.47 plus tax.

my plan is to test these items:

how noisey the pump is
how effective it is at pumping water through plumbing
how long it runs off my 7aH 12v gell-cell battery

The instructions on the pump do not have any warnings about continous operation of the pump, but I'm sure it's not designed to run continously for years on end like a mag-drive or any other aquarium pump

My hope is to find a solution to temporary short and medium term power outages without having to resort to using expensive UPS systems or generators.

Here's some pictures:

[RogerMcAllen]

You are testing noise, eh?
"I'm sorry little fishies, but you have to die because my backup pump is tooo noisy. I hope you understand."

Sounds good, let us know how it works.

[justDIY]

HAH

no, i'm sure the fish won't mind the noise, but I do ... I like a silent tank, or at least, not thing that HUM like pumps (air or water).

the whoose of air is ok, even some trickling water - but humming drives me crazy!

[justDIY]

here's some pics of the battery I will be testing the pump with.

My calculations give me about 3 hrs of runtime from this battery on a full charge.

Not enough to last a big power outage, but I'm just testin here.

A 500 or 1000 Ah marine deepcycle battery would run this pump for days, if not weeks for the 1000

[justDIY]

running off my battery, I calculated about 450 GPH - probably because the battery isn't as powerfull as a boat battery.

running off a 12 volt transformer I calcuated about 600gph, but the pump was overloading the transformer too.

the pump appears to draw about 3 amps at <2 foot head.

I will test again this weekend using an automotive battery charger, which should be able to meet the pumps demands.

[BillyZ]

with a 12v power supply from radio shack this seems like the perfect waterchange pump... ?

[justDIY]

naw

get a maxijet or a rio or something ... they all run off house power.

the current draw on this pump rules out nearly all the common "plug-in" type transformers, radio shacks 3amp cb power supply is the only thing that would 'safely' power this unit without being overloaded.

The biggest "wall-wart" style transformer I could find at the 'shack was 1500mA, which is half of what this unit requires... the transformer I was using is only rated at 1000mA - it got HOT after running the pump for a few hours.

By the time you added a sufficient power supply to run the pump off household power, it has become about the same cost as a cheap pump, not to mention less efficient.

Really the only thing this pump is applicable for would be emergency use, when there is no household power, you can connect it to a battery and keep the water circulating for hours or days depending on the battery.

[astride13]

I use a UPS battery backup like on a computer. You can get an APC 1000kva for $150.00 at Office Depot and online for much cheaper. It will run the pumps on a normal size tank < 200gals. for at least a day. I don't put the lights on it because I would rather extend the time for the pumps and the fish don't mind being in the dark instead of dieing.

You could probably get away with a 500kva that sells for around $50.00. Since the average pump/PH is only 1amp (110 watts), you could run 4 pumps.

[justDIY]

hmm - you are lucky!

I tried running a single maxijet 1000 (17 watts) off a 300 va ups, and it only ran for 1 hour 16 min.

although watts and volt amps are not completely interchangable, if we round 17 up to 20, it should be close enough

so at 20va, a 300va ups should have given me roughly 15 hours assuming perfect efficiency.

so why did it only run for a little over an hour? I mean, given 50% efficency, it should have run at least 7 hours.

Perhaps my UPS is bad, but I think the real cause is that most UPS are designed to run best at a 30 to 50% load, and only last 15-30 min.

I will do some more research on this matter shortly.

[sumphead]

Just a thought. Buy a generator. That way you can save the tank and the wife can do her hair in the event of a power outage.

[justDIY]

lol ... saving the hair and the tank

yea, a generator is a must if you want to have lights, heaters and all your accessories run in the event of an outage

but some of us live in situations where we cannot have a generator or the cost $100-$5000 is excessive for the needs.

I've been too busy to play with this pump much - maybe this weekend!

[astride13]

Unless you are just planning on running your aquarium and wife's hair dryer (This sounds like you have some bad ideas putting these together) you will need a big generator. A small 8k generator at Home Depot cost $1000.00. This would hardly run an average house, especially since a power outage is normally for a reason like snow or bad weather. If you run an electric heater (Sorry, I live in Florida, heaters are not in my expertise) you would probably be over 8k. Then if the wife decides to do laundry you are screwed.

We had a small power outage one night, lasted about 2 hours. I ran a 27" TV off my computer's UPS and it died about the time power came back online. A good quality UPS can give good results. Like I said earlier in this thread, I have a 1000kva UPS that cost less than $150.00 and it will run my aquarium for atleast a day.

As for the battery operated pump, My bilge pump on my boat has ran for days on a single 12v deep cycle. (float switch got stuck) When I noticed it was running, I fixed it and the battery still had the power to start to outboard motor.

The main fall back I see with the battery operated pump is if the power outage is while you are at work and you don't know for hours. This is why I opted for the UPS since it is automatic.