Last one for now - phew!
- Thread starter Lisahi
- Start date
Help Support Van Living Forum:
rvpopeye said:
Ah, PopEye! You're here too! And those inverters (?) - the things that convert 12 volt to AC, do they use energy too? I'm wondering, if I have an appliance that I really would like to use on the road, say for example, a Crock Pot (don't laugh), which says on the bottom of the appliance it uses 180 watts - what's the conversion formula for amps to watts? Also, I do realize a slow cooker is plugged in for a long time, maybe 6 - 8 hours on the low (180 watt) setting, and unless I've got lots of house battery charge or a big solar panel system and sunny days, that's probably not the best example, but still, a girl can dream, right? I do sometimes multitask: cook and drive using a CrockPot on long trips using this thing I bought at Radio Shack (is it an inverter?) that plugs into the car's cigarette lighter (12 volt?) and then I plug the normal 2-prong house plug of the Crock Pot into it. How about a laptop computer? Seems all the rv-ers have those. The laptops must need an inverter and I don't know how much amps/watts they use over an hour. Oh boy, hope I'm not making your eyes glaze over!
66788
Well-known member
- Joined
- Mar 5, 2014
- Messages
- 1,035
- Reaction score
- 8
Your answer to the amperage rating question is "maybe."
My ARB compressor fridge draws 2 amps (Amp Hours) but it only runs about 10 minutes an hour, so although when running it draws 2 amps, it would take 6 hours of constant use to equal the 2 amp draw.
As for your crock pot, forget it. Cooking with electricity calls for a huge battery bank and a lot of solar panels to support it. Inverters do use electricity in the conversion process, as they are not 100% efficient.
Think pressure cooker for your meals.
My ARB compressor fridge draws 2 amps (Amp Hours) but it only runs about 10 minutes an hour, so although when running it draws 2 amps, it would take 6 hours of constant use to equal the 2 amp draw.
As for your crock pot, forget it. Cooking with electricity calls for a huge battery bank and a lot of solar panels to support it. Inverters do use electricity in the conversion process, as they are not 100% efficient.
Think pressure cooker for your meals.
eDJ_
Well-known member
There are a large number of businesses online that sell 12 volt appliances. Like this one,
http://www.roadtrucker.com/12-volt-appliance/12-volt-appliances.htm
If you are on the road there are truck stops like "Pilot" that carry a large selection of these.
This site reviews the five most basic things to have if you live on the road.
https://www.thehealthytrucker.net/5-truck-cooking-appliances/
The 12 volt cooler may be called to question. Many here take a 36 quart plastic ice chest and
purchase 2 inch thick insulation board and build a box to put the cooler in. Thus an 8 lb bag of
ice can keep food cool for an extended period of time.
Here is a Youtube 10 day cooler conversion video that shows how it is done.
[video=dailymotion]
http://www.roadtrucker.com/12-volt-appliance/12-volt-appliances.htm
If you are on the road there are truck stops like "Pilot" that carry a large selection of these.
This site reviews the five most basic things to have if you live on the road.
https://www.thehealthytrucker.net/5-truck-cooking-appliances/
The 12 volt cooler may be called to question. Many here take a 36 quart plastic ice chest and
purchase 2 inch thick insulation board and build a box to put the cooler in. Thus an 8 lb bag of
ice can keep food cool for an extended period of time.
Here is a Youtube 10 day cooler conversion video that shows how it is done.
[video=dailymotion]
rvpopeye
Well-known member
- Joined
- Apr 21, 2015
- Messages
- 5,239
- Reaction score
- 5
Lisa
The conversion formula is watts (180) divided by volts (120) equals amps (1.5)
Yes the Rat Shack thingie is an inverter. It's a modified sine wave (msw)version.
There are also pure sine wave (psw)versions that are best if you need to power sensitive electronics like a laptop and some motor driven devices (like a fridge) although some will run fine on the cheaper msw versions.
And yes they do use power in the conversion , as well as just sitting there plugged in , like 66788 said.
Using it like you have going down the road is a good way to use it and have dinner cooked when you arrive at your destination !
(I've actually wrapped some things in foil and cooked on top of the engine...(some experimentation on time and location required !)
Those 12 volt appliances at the truck stop eDJ gave you links to are some great stuff and lots of people , including truckers use them successfully .
For a laptop , the best way is the 12volt cord power adapter Got Smart mentioned.
or if you don't need to do heavy computing and don't have a laptop already....
Maybe a tablet computer that charges from USB would be the answer.
Eyes glaze over right back atcha !
The conversion formula is watts (180) divided by volts (120) equals amps (1.5)
Yes the Rat Shack thingie is an inverter. It's a modified sine wave (msw)version.
There are also pure sine wave (psw)versions that are best if you need to power sensitive electronics like a laptop and some motor driven devices (like a fridge) although some will run fine on the cheaper msw versions.
And yes they do use power in the conversion , as well as just sitting there plugged in , like 66788 said.
Using it like you have going down the road is a good way to use it and have dinner cooked when you arrive at your destination !
(I've actually wrapped some things in foil and cooked on top of the engine...(some experimentation on time and location required !)
Those 12 volt appliances at the truck stop eDJ gave you links to are some great stuff and lots of people , including truckers use them successfully .
For a laptop , the best way is the 12volt cord power adapter Got Smart mentioned.
or if you don't need to do heavy computing and don't have a laptop already....
Maybe a tablet computer that charges from USB would be the answer.
Eyes glaze over right back atcha !
steamjam1
Well-known member
- Joined
- Dec 11, 2013
- Messages
- 861
- Reaction score
- 0
Lisahi said:
This is what I did trying to figure out power needs:
[img=295x365]http://www.p3international.com/products/images/main_p4400.jpg[/img]
I went and bought a Kill-a-Watt and saw exactly how much power @110V things use to run. I plugged in my coffee machine, my laptop, cell phone charger, and anything else I could think of including a dorm fridge I useto use. Then once you get the amp draw, multiply that number by 10 (General rule, Its not precise, but itll give you a ball park idea) of how many amps it will raw from a 12V battery through an inverter.
For example, My Mr. Coffee 4-cup coffee machine claimed 600 watts @ 110V. I plugged it into the kill-a-watt and saw it drew 535watts when brewing. Then its Watts divided by volts equals amps. (535w/110v=4.86a) To estimate the load to the 12v battery multiply the amps by 10. So the battery would have to supply 48.6 amps per hour to the inverter to power the 110V appliance.
Well atleast its worked pretty successfully for me. It got me to see what I could run, and a ballpark number on how long I can run it for until the low battery alarm goes off on my inverter. (1000watts)
DannyB1954
Well-known member
Watts equals amps times volts. As an example the crock pot mentioned at 180 watts would draw about 1.5 amps at 120 volts. Now if you are running it through an inverter that 180 watts at 12 volts would be 15 amps, plus add a bit for the inefficiency of the inverter. Crock pots usually run for hours. I don't think most batteries could handle that. An amp hour is a one amp draw for an hour. A 100 amp hour battery can be drained down to 60% of it's charge, so about 40 amp hours could be used. 40 divided by 15 is about 2 1/2 hours of crock potting.
Now if you are driving down the road and want to cook while you travel, the vehicle's alternator should be able to keep up quite well.
Now if you are driving down the road and want to cook while you travel, the vehicle's alternator should be able to keep up quite well.
DannyB1954
Well-known member
I should have added that solar panels can help, but you would need 200 watts of panels running at full output to break even.
Driving down the road cooking will also cost you gas mileage. It takes energy to turn an alternator under a load.
I had a truck drriver friend who used a 12 volt oven. It worked well, but it was small, (like a lunch box), and the truck had a 200 amp alternator.
Driving down the road cooking will also cost you gas mileage. It takes energy to turn an alternator under a load.
I had a truck drriver friend who used a 12 volt oven. It worked well, but it was small, (like a lunch box), and the truck had a 200 amp alternator.
masterplumber
Well-known member
- Joined
- Nov 6, 2013
- Messages
- 1,277
- Reaction score
- 0
I use a regular crock pot, run off an inverter in my trailer, but I only run it while driving between camps. It works awesome for that and it's nice to have a hot meal ready when you arrive. I was going to get a 12 volt model, but the reviews were not stellar. It seemed like when they worked they were ok - pretty simple technology so hard to mess up. But since almost all of the 12 volt ones are made in China they were made from the cheapest lightest components available. Way to high a percentage would stop working after a couple uses, or not at all, and more than a few even caught on fire from the to small of wire over heating. I just wasn't willing to risk it, and I figured I'd have to be driving to be able to use it due to energy draw anyway. Also, one more bit of info - crock pots draw the same amount of power when on whether on high or low - they just run the heat element less on low. Kind of like the example above of the fridge drawing 2 amps, but only running 10 minutes per hour. I did a lot of research leading up to this, as I really wanted to like the 12 volt models, and an inverter definitely draws some extra power while doing it's job. But for me this turned out to be the best solution, and I've been using it for a while now.
Similar threads
