New Sump pumps save power..
 

Found these new 1/3 HP pumps that only use about 300 watts..

Basement Watchdog BW1033 - 1/3 HP Submersible Sump Pump

http://i46.photobucket.com/albums/f1.../2newpumps.jpg


Since I was adding 3 new sump pumps, I looked around for some that
wouldn't be power hogs. I should be able to fire all these up for less than 1kW..

3200 GPH is about 53 gallons a minute. So, no problem keeping up..

The float & control is separate from the pump (for easy replacement)
and has a 10-12 second ON delay after the float drops.
Meaning it's going to get down to the bottom of the barrel.. :cool:

~~~


I've got a little 12VDC to 120VAC inverter that has:
Maximum Continuous Power 400W
Surge Capability( Peak Power) 800W

http://ecorenovator.org/forum/applia....html#post5904


I wonder if it has the guts to start up and run one of these little 1/3HP pumps?

I'm thinking about using the two big LA 12V batteries that I have on my solar chargers..

Humm,

[10w PV]---[Charger]---[12V LA]---[Inverter]---[300w pump]

My sump pump (also 1/3hp) starts up @ about 1200W max I think and quickly declines to about 300W as well.

1200W !! Wow.. I have a feeling that maybe I should refrain from plugging
one of these new pumps into my new inverter!! :eek:

Modify the inverter to perform a V/Hz soft start.

I know what a soft-start is, but I'm not familiar with the circuitry that
would be used in a 12Vdc to 120Vac inverter.

The cheapo Rosewill inverter has some interesting specs.
Rosewill.com - Accessories, Car Electronics, Power Inverter, RCP-511F

# Overload Protection
# Short protection
# High Voltage protection
# Low voltage audible alarm
# Low voltage protection
# Thermal protection


I wonder if the Overload Protection & Short protection
would allow it to survive a start-up current surge of the little 1/3 HP pump motor..?.

Edit:
Haha! I just went back and actually read the manual to the last page and found
it CAN handle some high starting currents, like a 3/4" drill...
So, I plugged in a pump and it ran okay..

If it could handle that pump being switched off and on 30 times an hour, is another story..

How does that compare to other pumps as far as GPM per watt goes?
Does your inverter give a duty rating or anything else like that?
I would think if it was seeing to much surge in an hour it would over heat and trip a thermo over load switch, another option might be to see if you can adjust the pump so it has longer cycles, so it fills with more water before kicking on.

Are these a trash pump, or a simple sump pump? because we use a trash pump at work in a pit to pump out mud (granite counter top shop) and that over run feature sounds nice to make sure all the water gets pumped out.

It says 3200 GPH, which is about 53 gallons a minute.. Which is a lot more capacity than I'll ever need.
I was less concerned about the per/watt as I was about the total watts used.
From what I found looking at these things, 300 watts is pretty low usage.

Because the size of the sump holes are not that big, the amount of water removed in a cycle is pretty small. At 0.89 gallons a second, all the water will be gone in about 10 seconds. And because of the way the float delay works, the pump will turn off a couple seconds later.
No need to worry about the inverter overheating. :)

Not a trash pump.. Made for dirty water only. Three years warranty for sump-pumping and one year for continuous duty (fountains etc)..
During continuous duty, the pump must be at least 2/3 underwater..
For cooling.

Maybe you can use a 12v bilge pump as the primary pump?

I did some reading on automatic 12V bilge pumps and found some that might have been suitable.

But after considering the changing weather and other factors,
I decided to go with old-tech. I wanted to use proven hardware.
Devices that had a reputation for many years of unattended performance.

Whereas a 12V system requires periodic testing the backup battery, cleaning the PV panels etc..

I asked myself, what system is going to last 10 to 20 years with having to even look at it?
What system will my wife be able to get repaired, in the likely event of my demise? :eek:

I finally got the last pump installed. Made an 11" hole in the floor (which is about 3-4" thick).

Started pulling out some softball sized rocks out down to about 8" to 10".
Then, I ran into a really big rock. About 80-90 pounds, like a rock watermelon. :mad:
It was about 15" across the thin part. No way to get it out of the 11" hole. :o
Before making to hole larger, I decided to see if I could trim some fat off the rock!
Got down in there with my little 2.5 pound hammer and rock chisel..
Took me about an hour, but I trimmed it down to 11". :)
Got it out. It was a real PITB getting it out to the backyard.

The bad news, there was an even larger rock under the watermelon.. :eek:

I hollowed out under the floor around the hole, added the filter (old outdoor carpet),
and used a 5 gal plastic bucket as the insert (drilled 1/2" hole first),
dropped in the pump and float switch. All done.. At last.. :)

I think the sump will hold about 20 gallons total. (Before over-flowing).
The pump should keep the level down to just a couple of quarts.