DIY marine deep cycle battery backup - seeking advice

[stevenp]

I've been kicking this idea around the past few days thinking that it would be a better solution than an APC (providing it's set up correctly/safely). I ran across this thread on RC. Post #6 has a nice diagram and shows pretty much what I had envisioned in my head, though I'd opt for much less expensive inverter as I would only want to run my GenX pump which only pulls 110w.

Hoping some of the electrical gurus can comment

 

[naturebatslast]

I have a UPC that's OK but have thought of the deep cycle to run a 3 small (20w) pumps, maybe a small heater. No electrical guru, but would you downsize the inverter as mentioned?

 

[stevenp]

would you downsize the inverter as mentioned?

Absolutely, the 1000w inverter would likely be cost prohibitive not to mention overkill.

 

[dcforester1]

I cant believe this is posted. I was just looking thru youtube not 10min ago, and watched a video on it. I was thinking of trying it myself. They showed how to do it with 2 batteries. It didnt look to difficult.

 

[stevenp]

I cant believe this is posted. I was just looking thru youtube not 10min ago, and watched a video on it. I was thinking of trying it myself. They showed how to do it with 2 batteries. It didnt look to difficult.

Cool, can you post a link to the video?

 

[dcforester1]

I am trying to find it. I was trying to find something else, and came across it. I also am not sure n how to post a link, but I will try.

 

[dcforester1]

Do you just copy, and paste it?

http://www.youtube.com/watch?v=r5H8m1isFy4

I think that will work. Let me know how you make out.

 

[Brad S]

Get a generator...

 

[jayman10134]

Get a generator...

+1 generators are the way to go.

 

[Blueflu1]

Just be careful. If the battery tender overcharges it and boils it, I believe that the batteries will release gasses into the house. I use a battery tender on my MC and lawn tractor batteries in the basement, but I wouldn't feel comfortable having them in the living area.

 

[Takara]

Just be careful. If the battery tender overcharges it and boils it, I believe that the batteries will release gasses into the house. I use a battery tender on my MC and lawn tractor batteries in the basement, but I wouldn't feel comfortable having them in the living area.

x2 charging batteries vent hydrogen gas, and some times leaks acid, be safe guys! You would need a trickle charger and something to hold the batteries that has a atmospheric vent.

 

[jayman10134]

Just be careful. If the battery tender overcharges it and boils it, I believe that the batteries will release gasses into the house. I use a battery tender on my MC and lawn tractor batteries in the basement, but I wouldn't feel comfortable having them in the living area.

+1, i once overcharged my motorcycle battery with a trickle charger it overflowed. so just be very careful. battery acid is not something i would want in my house.

 

[MikeG]

Get a generator...

+1 generators are the way to go.

Steve has a generator that will run pretty much his whole house and tank. I am sure he is looking at this to automatically switch power over in case he isn't home to hook up the generator.

 

[stevenp]

As Mike mentioned I have a good size generator for extended outages. I want a battery backup so when the power goes out at 3am like it did two weeks ago I don't have to climb out of bed, lug the generator out of the garage and hook it up to run the tank for 4 hours.

Before anyone mentions battery backup air pumps, I have plenty of those too but I have a couple issues with them: 1) they throw salt mist into the air and make a mess, and 2) I have several SPS colonies that have grown to the water surface which are exposed when the water level drops. I would still plan the keep these online though, but they'll activate only after the battery backup runs out of juice (by then the generator will likely be running though).

Point taken on gases leaking while the battery is on the trickle charger. Does the battery have to be on a trickle charger though? Couldn't you just charge it a couple times a year to keep it conditioned? I store my boat batteries in the basement every winter and every spring they seem to be fully charged.

 

[BigBubba]

I've been kicking this idea around the past few days thinking that it would be a better solution than an APC (providing it's set up correctly/safely). I ran across this thread on RC. Post #6 has a nice diagram and shows pretty much what I had envisioned in my head, though I'd opt for much less expensive inverter as I would only want to run my GenX pump which only pulls 110w.

Hoping some of the electrical gurus can comment

I was looking for solutions similar to this last year and ended up making my own. I looked at the different inverters but didn't like the idea of having everything wired up with a possibility of a short somewhere or something falling apart. I did some research online and ended up buying an APC UPS, a Smart-UPS 1400. I worked out a deal and bought the unit without the original batteries. When the unit arrived I attached 2x 12v 75ah sealed lead acid batteries to the unit. The batteries are huge and have to sit beside the unit. The 1400 takes a long time to charge those batteries but because of their size and capacity, I have over 24 hours of run time. Also, SLA batteries are safe indoors. It isn't the prettiest set up ever, but I get power filtering, avr boost/drop, surge protection and a very long run time. At the end of the day, probably cheaper than some high end inverters.

 

[Brad S]

As Mike mentioned I have a good size generator for extended outages. I want a battery backup so when the power goes out at 3am like it did two weeks ago I don't have to climb out of bed, lug the generator out of the garage and hook it up to run the tank for 4 hours.

Before anyone mentions battery backup air pumps, I have plenty of those too but I have a couple issues with them: 1) they throw salt mist into the air and make a mess, and 2) I have several SPS colonies that have grown to the water surface which are exposed when the water level drops. I would still plan the keep these online though, but they'll activate only after the battery backup runs out of juice (by then the generator will likely be running though).

Point taken on gases leaking while the battery is on the trickle charger. Does the battery have to be on a trickle charger though? Couldn't you just charge it a couple times a year to keep it conditioned? I store my boat batteries in the basement every winter and every spring they seem to be fully charged.

Eh, tank being off for 4 hours isn't going to do anything to it at all... Seems like more trouble than its worth, car batteries are finicky about being overcharge plus sometimes they spew acid.

 

[BigBubba]

Eh, tank being off for 4 hours isn't going to do anything to it at all... Seems like more trouble than its worth, car batteries are finicky about being overcharge plus sometimes they spew acid.

Car batteries are definitely not safe to be kept indoors. If one must use them, keep them outside in a well vented area. Personally, I wouldn't use them.

 

[marco67]

I run this http://www.invertersrus.com/trippliteaps1250.html
With 2 deep cycle marine batteries
It runs a large system with quite a few pumps and power heads for a good 10 hrs.
It's been on my system about 6 years now without issue.

 

[stevenp]

Thanks Marc. I'll check those out.

 

[Fish Ace]

Get one of these and you will never have to worry and get out of bed again. About $2k not installed.