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DC sump pump?

kanelr

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Mar 1, 2022
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can I run two 12v DC sump pumps in series on a good 24v system? may be simplest way.....? two pumps will fit in most crocks.
 
I don't really know, but I would not think it would work very well. A lot of it depends on the type of DC motor
 
can I run two 12v DC sump pumps in series on a good 24v system? may be simplest way.....? two pumps will fit in most crocks.
Play around with Ohm's law and see what it says.

Why not just get a 24v pump?
 
As long as all works forever then all is fine. If something happens to one then good chance of losing both.
Besides most of these 12v pumps seem kinda weak..... unless that is all that is needed.
 
I don't think this is the best or the most efficient way to obtain a good system of 24v. However, I'm not a professional, and I can't assure you that I am right. You can try to contact companies like https://www.sumppumpadvisor.com that are more informed in this domain and can provide you with a real solution. I've been collaborating with them for the past years, and they were always extremely helpful. On top of that, they have on their website a ton of useful information and even the type of models described with details to help you make the best decision.
 
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What turns them on and off? If it is a float switch, the switch on both will have to be "on" at the same time for them to turn on. If one switch were to somehow fail, the other pump would be off as well. Two pumps in series will double the chance of a failure event.
 
How would a backup for the sump pump work on solar? Would a battery, solar panel and inverter and charge controller work and is it that simple? Also what wattage inverter and controller would I need for this? Current pump plugged into a dedicate outlet with it's own trip breaker. Thanks.
 
How would a backup for the sump pump work on solar? Would a battery, solar panel and inverter and charge controller work and is it that simple? Also what wattage inverter and controller would I need for this? Current pump plugged into a dedicate outlet with it's own trip breaker. Thanks.
Take for example you have a 1/4hp to 1/3hp pump that would run on 120v AC and need about 200w-300w to run and maybe more to start. So a 1000w inverter should be large enough. Under normal conditions you could run the pump off of the house AC. But if the AC was out, you need the inverter and a battery. The battery will only last so long, so you need to charge it, say with solar.

Assume the pump needs to run 15 minutes per hour, it would need 6 hours of run time per 24 hours. 6hrx250w would be 1.5kwh. So a lithium battery that could deliver 1.5kwh would run the pump for about a 24 hour day. Maybe double that if you really need the battery to carry you in the case of cloudy weather. But when the sun comes out, it would be nice to put one day's worth (1.5kwh) charge back in the battery in maybe 4 hours. With losses you need more than 1.5kwh of power and panels are normally producing less than their rating. So say 600w worth of panels might give you 0.5kwh to the battery per hour. So in 3 hours of sun (at mid day) you might get 1.5kwh to the battery with 600w of panels.

A person could put an AC charger on the battery to keep it charged and store the panels. But then you would need to get it all out and connected up in the event of emergency. If you need it to be sort of automatic, you can run off the battery/inverter all of the time and have both solar and AC charging the battery, so it is always ready. Some inverters have internal switching to act as a UPS, if that level of automation is needed.
 
How would a backup for the sump pump work on solar? Would a battery, solar panel and inverter and charge controller work and is it that simple? Also what wattage inverter and controller would I need for this? Current pump plugged into a dedicate outlet with it's own trip breaker. Thanks.
A 12v DC sump pump that could connect to a car(battery) could be a fair backup.
 
can I run two 12v DC sump pumps in series on a good 24v system? may be simplest way.....? two pumps will fit in most crocks.
Yes, 24 V will make the pump go faster than 12 V. It will use more electricity, but it will also pump water faster. Even though 24 V is on for less time, the total amount of energy used to pump the same amount of water will be higher than with 12 V.
 
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