Chainsaw's Simple 12V DIY Backup System

Zman

Outbackozzie wrote:

he air pump is a 35w model, which draws around 3.2 Amps. A 100 AH battery will provide around 20 hours of runtime, after which the air supply will keep running, but at a pretty rapidly reducing rate. I'd say 25 hours would be about the max.

Hi Col,

Sorry to be a pain but can you tell me how the conversion is done (amps to AH)?

jet

Zman wrote:

Would this be ok for the trickle charge?

http://www.ebay.com.au/itm/12-Volt-Smar ... 19c6596730

Yes should be fine BUT only tiny charge rate, maybe not enought to recharge big battery bank in a reasonable time, ie a flat 100A/hr battery might take 6 days to recharge.

Outbackozzie

Zman, I measure the current draw in amps, then it's simply a case of dividing the battery capacity in 2 to get 50% of full capacity ( you don't want to discharge below this all the time ) ie 100ah becomes 50ah - this will run a 1a load for around 50 hours. A 10a load will only get around 4 hours though, due to higher draws using the battery capacity differently.

Zman

Ah ok, so basically in the 35W, drawing say 3 amps, and i have a 60AH, at 50% i would have roughly 10 hours right?

jet, where do you look how much/fast they charge? Is there something to look for?

Outbackozzie

That's about right, and the description in the eBay link says it charges @ 1/3rd of an amp-hence the slowness.

jet

Outbackozzie wrote:

That's about right, and the description in the eBay link says it charges @ 1/3rd of an amp-hence the slowness.

Yep what he said,
Mostly the charge rate is what you pay for, smart chargers have the ability to run down to tiny charge rate when the battery is full.

Zman

So say to recharge 10 AH i would have to wait 30 hours?

Outbackozzie

10ah / 0.35a charge rate. So close to 30 hours. Quite a while.

RBEglobal

Use a CTEK battery charger. Concorde Sun Extender AGM batteries recommends them.
I have a Schumacher from Wal-Mart $40...not really good.

This CTEK also has a "power supply" mode. It can run up to 6A directly.

http://www.amazon.com/CTEK-Multi-7002-B ... B000FRLO9Y

BNDYBEAR

Set my backup up tonight, just follow these instructions its all extremely easy and safe.
Got the relay from jaycar and also a 240-12V AC Adaptor pretty cheap from there too.
Had the battery and power pack, and purchase the same pump from Guppy's.
I pumps a fair bit of air! I just need to get some more airline and air stones now!

Feel so much more relaxed now, especially with the warmer days lately, I've been having nightmare flash back to last year. Lost 7 trout last year, this year I've got 70!

BullwinkleII

thanks people

BNDYBEAR

Anyone running trout late into this Autumn needs a backup, it doesn;t matter where you live.

BnBob

Just wondering, what size FT is the original post set up for chainsaw ?? Couldn't see it anywhere..

Ed to add...
Anyone purchased a trickle feed charger recently???
Got any recommendations??

Thanks..

chainsaw

Hi BB, I have 6 stones running off it, one in each tank 5 are IBC's and a 5000 Ltr round tank. I have since made a second one using different relay and power supply. The original still works fine.

Jackfrost

Do you reckon I'd get away with this for a 600L FT? I'm actually looking at running an air pump 24/7 by hooking it up to a battery that stays charged by a solar panel so there is no reliance on power

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