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strangemojo
Oct 27, 2016, 11:27 AM
Hello all,

I have a waste water lift station on my property that I am responsible for. Since the sewer is up the hill from my home, my waste water collects in a cistern that is set into the ground on one side of my property. There is a big old pump at the bottom of this cistern with a float activator that turns on the pump when the water level rises.

I have found that when the power goes out and this waste water rises above its usual pump level, the floater can get stuck. The result is that when the power comes back on, the pump goes to work and never turns off due to the stuck floater switch.

For the handful of times that the power goes out a year, I would like to get a battery backup system that will power the pump when the grid is down.

Looking for suggestions in terms of a product to do this and any advice on the project that might be relevant.

Thanks,
Mojo

ma0641
Oct 27, 2016, 02:18 PM
How much HP is the existing pump motor? What is the head elevation? big old pump
You might be surprised how big a battery system you would need AND a pump that would run on DC or a fairly large Inverter. A 1/2 HP inverter on eBay runs about $500. Might be easier to tether the float so it doesn't go up so far. Where does the effluent go when the cistern overflows?

strangemojo
Oct 27, 2016, 02:40 PM
How much HP is the existing pump motor? What is the head elevation? big old pump
You might be surprised how big a battery system you would need AND a pump that would run on DC or a fairly large Inverter. A 1/2 HP inverter on eBay runs about $500. Might be easier to tether the float so it doesn't go up so far. Where does the effluent go when the cistern overflows?

So the pump cost me about $2,500. Here are the details:

Barnes 132848
Model 3SE2022L,
Submersible Sewage Pump,
2 HP,
230 Volts,
1 Phase,
3450 RPM,
3" NPT Vertical Discharge,
160 GPM Maximum,
78 ft. Maximum Head,
Single Seal,
30 ft. Cord


It has to pump the sewage up a hill, about 150 feet with an incline of approximately 50 degrees, so its moving a good volume of water.


The cistern is about 2.5 feet deep at the bottom of a redwood lined 7 foot pit. The waste just continues to rise until it hits the waste pipe, when this occurs there is a relief outflow situated in my front yard - the crap (literally) just flows out into the yard when there is a blockage or the pump is not pumping.


M

ma0641
Oct 27, 2016, 02:57 PM
"The waste just continues to rise until it hits the waste pipe, when this occurs there is a relief outflow situated in my front yard - the crap (literally) just flows out into the yard when there is a blockage or the pump is not pumping".

The city or county allows this to happen with raw sewerage? EPA would flip on this!! You are looking at a massive battery supply and inverter. I would expect you would spend at least the same amount for an AC/DC motor PLUS control panel and batteries. There are some 1/2 HP units for $500 BUT they are limited to 10 ft. lift.

Why are you responsible? Private utility?

Fr_Chuck
Oct 27, 2016, 06:59 PM
Perhaps a gas operated sewage pump, that can be ran when needed for emergency operations.

smoothy
Oct 27, 2016, 07:45 PM
I'd go with a diesel powered electric start generator tied to it with a battery tender to keep the starter battery ready to go tied to an automatic transfer switch. Diesel because gas goes stale when not used up in just a few months and will be a maintenance issue by the second year. . OR one that is duel fuel and will run on propane which might be cheaper.

But I also have to ask as others have... why this is your problem?

Milo Dolezal
Oct 28, 2016, 05:47 AM
Aside from the battery...

You should check the float installation. It may not be installed properly. It may be hung too low. If installed properly, the float should not get stuck, even if the cistern fills all the way to the top

Hope that helps

Milo

hkstroud
Oct 28, 2016, 09:59 AM
I would consider a whole house generator and get the benefits of having electrical power for critical circuits of the entire house during power outages as well as sewage removal.

jlisenbe
Oct 29, 2016, 11:20 AM
Yeah. A generator would be a lot easier and probably more dependable, not to mention cheaper. Assuming that you are there most of the time, then a gen would do it.

This is, I think, your pump. Pulls about 14 amps when running and, no doubt, more than that when starting. That would be a fairly demanding battery setup.

https://www.pumpproducts.com/barnes-132848-model-3se2022l-3se-series-sewage-pump-hp-230-volts-phase-npt-vertical-discharge-160-gpm-max-78-ft-max-head-30-ft-cord-manual-single-seal-p-539758.html (https://www.pumpproducts.com/barnes-132848-model-3se2022l-3se-series-sewage-pump-hp-230-volts-phase-npt-vertical-discharge-160-gpm-max-78-ft-max-head-30-ft-cord-manual-single-seal-p-539758.html)