# Battery and inverter questions



## Aquaman (Apr 21, 2010)

Hey guys...So I picked up a camper .LOL I will be living in it for 4 months or so and need info on inverters, battries etc.

What is the best brand if any and how big do i need ? 1200 3000 ? ( whats a comp. and small microwave pull for power . also marine battery v/s gel cell batteries ? and last of all should I be getting a BIG 12 volt or 2- 6 volt batteries ? 
Any camper specialists out there 
thanks 
bill


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## spit.fire (Jan 3, 2011)

im not to sure if you'd be able to run a microwave off of an inverter but your best bet would be to look on the tag on the microwave to see how many watts it pulls. also are you planning on running a laptop or a desktop? laptops dont need as much power to run. Marine deep cycle batteries would be sufficient where as gel cell batteries will cost you alot more money and i dont think you would really notice the difference for your application. And i would suggest a big 12volt over 2 6volt

how often will the battery get charged / used?


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## Aquaman (Apr 21, 2010)

Well I just checked the microwave ...power consumption 1.35 kw ( is that 1350 watts? ) max output of microwave is 900 watt ( means nothing in this case I think ).
I was htinking of gel cell for storage as well ( to lay them others on thier side ) ..I had heard that 2 -6's would give you a better load capacity ? . Also thinking storage ...tho never seen a 6 volt gel cell come to think of it lol.
Charging would be only with the truck ..untill I figure out something else.Would depend on how long the battery lasts .Most likely every day I would be driving .
I understand I need more amp hours than I do cold cranking amps ...so that will play a big part.
any one have exp. on how long this type of power lasts ? any examples would be appreciated.


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## ninez (Apr 21, 2010)

Bill

After I followed your advice on longer output hose than input hose to prevent bubbling on the canister (it worked), I thought you are a genius.
I thought you knew *EVERYTHING*!!


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## Aquaman (Apr 21, 2010)

found this info on line 

You'd need to know how many amp hours (Ah) or reserve minutes (RC or RM) your battery can sustain. There will be a label on your car's battery that will say something to the effect of 75-Ah or xx-RC. These ratings are essentially one in the same.

Reserve capacity states how many minutes a battery can have 25 amps drawn upon it before dropping to a voltage of 10.5 volts.

The Amp Hour rating tells you how many amps are available when a load discharges your battery evenly over a 20 hour period.

Example: A car battery that has a rating of 75Ah, dividing by 20 = 3.75. This battery can carry a 3.75 amp load for 20 hours before dropping to 10.5 volts.

Conversely, if your car's battery had a 75Ah rating, and this inverter draws 75 amps fully loaded, your battery will last only 1 hour.

You can calculate this yourself by finding your battery Ah rating and diving by the loaded current draw of the inverter. Example: 75Ah/75Amps=1 hour OR 75Ah/100Amps=45 minutes
Sounds like I will need 3 batteries lol...j/k. Must find out the draw on the inverter first i suppose.


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## airbaggedmazda (Apr 27, 2010)

I have a trailer and also used to compete in car audio comps. and we had stereos that would draw well over 300amps. 

Saying that 2 six volts will have a huge amount of storage capacity but will take longer to recharge, of course it would depend on how much you have drained them. They would probably last you 2 or 3 days before having to recharge.

If you were running 1 of 12v it would not last very long running your desktop.

Pretty much all new trailers come with at least 2 6v, alot of them have 4 6v


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## airbaggedmazda (Apr 27, 2010)

The inverter draw would also depend on what it is running at that time


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## Mferko (Jun 8, 2010)

Aquaman said:


> Well I just checked the microwave ...power consumption 1.35 kw ( is that 1350 watts? ) max output of microwave is 900 watt ( means nothing in this case I think ).
> I was htinking of gel cell for storage as well ( to lay them others on thier side ) ..I had heard that 2 -6's would give you a better load capacity ? . Also thinking storage ...tho never seen a 6 volt gel cell come to think of it lol.
> Charging would be only with the truck ..untill I figure out something else.Would depend on how long the battery lasts .Most likely every day I would be driving .
> I understand I need more amp hours than I do cold cranking amps ...so that will play a big part.
> any one have exp. on how long this type of power lasts ? any examples would be appreciated.


yes thats 1350 watts, add up all the wattages of all your appliances to figure out how much capacity you need

if your 12V battery can only source 25amps thats 300 watts..., 4 of them would be 1200

and your right the cold cranking amps isnt too important in your situation, motors draw alot more current when the rotor is locked (upon startup) so your starter needs to be able to draw alot of current from a cold battery to turn the engine over


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## doogie (Nov 5, 2010)

Hi Bill, just remember to add a solenoid to the system that isolates the truck when it is shut off from the camper, that way even if you forget and kill the campers batteries you can still start the truck.
D


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## Aquaman (Apr 21, 2010)

ninez said:


> Bill
> 
> After I followed your advice on longer output hose than input hose to prevent bubbling on the canister (it worked), I thought you are a genius.
> I thought you knew *EVERYTHING*!!


LOL thanks Zenin . I think ya meant think instead of thought and know instead of knew ...but I know you knew that or at least I thought you did ,I think. ( i hope you find this as confussing ) LOL 
Thanks man ...I just know a little bit of everything ...jack of all trades master of none ...well maybe one....


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## Theratboy_101 (Apr 27, 2010)

you mite want to take a trip to somewhere like edmonds batteries. They sell just about every kind of battery, charger, and inverters. 

5 or 6 years ago we picked up 2 6V 1100amp gel cells for my dads hotrod there. Since then I've gone back for other hard to find batteries and they always had what I wanted.


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## Aquaman (Apr 21, 2010)

Well I went with this converter 

SAM-2000-12 - SAM Series - RV Solar Power | Samlex Solar

and this battery

Trojan Battery Company

Dont know if its the best set up ....doesn't seem like a lot of run time on the batt. May need too get another  maybe....not sure yet .
Opinions appreciated !!


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## rescuepenguin (Apr 21, 2010)

looks like a good combination, too bad the larger inverters don't come with a USB charging port, it would consume less energy than plugging in a 110v charger. Don't forget the charge controller.

When you get the equipment charge the batteries, plug in the microwave and see what happens. If you need more amps buy another battery or 2 and connect them in series. If you want the power to last longer connect them in parallel. You have the option of plugging them in parallel and reconnect them in series when you need more power.

Are going to do solar back up for when the AC power is not available?


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## davefrombc (Apr 21, 2010)

Maybe we can connect in chat one evening Bill.. Your 1350w microwave would effectively drain that battery in just a few minutes operation. I doubt it would run it 10 minutes; and it wouldn't take many cycles from charged to dead before the battery would be toast. At 1350 watts, your inverter will be drawing approximately 150-160 amps on the battery, maybe even a little more. At 100% conversion , at 12 volts , 112.5 amps is needed to produce 1350 watts , but you have to allow for inverter efficiency (likely about 80%) and line losses.
If you haven't bought the inverter and battery yet , hold off until we can chat.
You'll be a lot wiser to pick up a 2500 watt generator to use when you need ac for your camper .


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