View Full Version : Bilge pump for battery backup

02-01-2014, 04:39 AM
I have been told that Bilge pumps are not good for continuous operation in Aquaponics, but I was wondering if they can be use in a battery backup setup for power outages or emergency only. I have an 80 watt solar panel, 70ah gel battery and a 30 watt 12 volt bilge pump (800gph) and was contemplating the idea of making a solar battery back up where it can keep my battery charged and run the Bilge pump during power outages.....any ideas?

02-01-2014, 09:16 AM
Yes, they will work fine for short periods of service, however don't forget that our power outages here in Fl. are usually due to stormy weather and thus lots of cloud cover.....will your solor panel still produce enough juice under dark skys to last a week? :mrgreen:

02-01-2014, 11:33 AM
I know what you mean.....I haven't seen the sun in 4 days here in Orlando. I only want to use the bilge pump when the power goes out and then switch back to the regular pump when the power comes back through a relay. The 12v bilge pump will be controlled by a relay to only come on when the power goes out and will be running off the 12v gel battery which is been trickle charge from the solar panel on a everyday basis. I'm hoping the battery is at full charge when I need it since is only been used for power outages only.... :roll:

02-05-2014, 11:39 AM
Well, I setup everything and so far everything is working perfect . I killed the main power, the bosh relay detected no power and it switched to the bilge pump circuit running of a gel battery that's been trickle charge from a solar panel, the bilge pump ran for about 6 hours without a hiccup as a test. I'm happy now….. :mrgreen:

02-05-2014, 12:02 PM
Very nice! Pictures and/or wiring diagrams for any who may follow in your footsteps?

02-05-2014, 08:52 PM
I'll see if I can get pictures with my phone, but for now I created a quick wiring diagram of the circuit :
http://i187.photobucket.com/albums/x295/elisamuels/Battery%20backup%20system/solarbatterybackup.jpg (http://s187.photobucket.com/user/elisamuels/media/Battery%20backup%20system/solarbatterybackup.jpg.html)

I am using a 12 volt wall plug transformer that I had laying around, it connects to the coil relay to turn it on,when the relay is on, the battery is connected from 87 to 30, when the power outage happens the coil looses power and then 87a connects to 30 and the Pump comes on. When the power comes back then 87 connects to 30 again and the Bilge pump shuts off.
I am using a 12 volt Solar panel to trickle charge my battery through a solar charge controller, Some people don't use the charge controller but I do for the reason been that the charge controller will prevent the battery from overcharging. 8-)

02-06-2014, 12:05 PM
Very nice! Great diagram.

02-16-2014, 08:24 AM
These are the solar panels I am using, I get around 6 hours of full sun:
http://i187.photobucket.com/albums/x295/elisamuels/Battery%20backup%20system/solarpanels.jpg (http://s187.photobucket.com/user/elisamuels/media/Battery%20backup%20system/solarpanels.jpg.html)

This is the solar charge controller:
http://i187.photobucket.com/albums/x295/elisamuels/Battery%20backup%20system/chargecontroller.jpg (http://s187.photobucket.com/user/elisamuels/media/Battery%20backup%20system/chargecontroller.jpg.html)

These are 2 gel batteries running in parallel being charge by the solar panel:
http://i187.photobucket.com/albums/x295/elisamuels/Battery%20backup%20system/battery.jpg (http://s187.photobucket.com/user/elisamuels/media/Battery%20backup%20system/battery.jpg.html)

This the Bilge pump that runs during power outages. I added a "T pvc" and installed a check valve with the Bilge pump on the left and to the right of the "T pvc" I am running the main pump Danner 9.5 with a check valve also.
http://i187.photobucket.com/albums/x295/elisamuels/Battery%20backup%20system/bilgepump.jpg (http://s187.photobucket.com/user/elisamuels/media/Battery%20backup%20system/bilgepump.jpg.html)

02-16-2014, 09:42 AM
GREAT set up...can you provide more information on what type of Bosh Relay you're using?

One additional piece information back to you, I've been told that concrete has a way of harming a battery. You should place a piece of wood between the battery and your cement blocks, it will also add some center support to your battery.

02-16-2014, 08:17 PM
I am using a 5 pin automotive bosh relay, I bought them locally for about $5.00 each but I have seem them online as low as $2.00 each: http://www.parts-express.com/12-vdc-aut ... e--330-073 (http://www.parts-express.com/12-vdc-automotive-5-pin-relay-spdt-30-40a-bosch-type--330-073)

http://i187.photobucket.com/albums/x295/elisamuels/Battery%20backup%20system/330-070_ALT_0.jpg (http://s187.photobucket.com/user/elisamuels/media/Battery%20backup%20system/330-070_ALT_0.jpg.html)

http://i187.photobucket.com/albums/x295/elisamuels/Battery%20backup%20system/RelayWiringGuide.jpg (http://s187.photobucket.com/user/elisamuels/media/Battery%20backup%20system/RelayWiringGuide.jpg.html)

I wasn't sure about the placement of the batteries, I'll get a piece of wood for them to get them off the cement blocks.

02-17-2014, 01:01 PM
Additional to the wood under the batteries, a thick layer of rubber will help maintain your battery charge. Any battery that is connected to the earth, whether it be sitting directly on the ground or on concrete will loose charge :mrgreen:

02-18-2014, 08:10 AM
Additional to the wood under the batteries, a thick layer of rubber will help maintain your battery charge. Any battery that is connected to the earth, whether it be sitting directly on the ground or on concrete will loose charge :mrgreen:
The wood and rubber are no longer necessary with today's battery construction. I grew up with this rule of placing the battery on wood. A few years ago, I found out that was a waste of time. :o :shock: :? Here is a link, http://www.thebatteryterminal.com/TechTalk_Batteries_on_Concrete.htm