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pianotuna
Hi,

I'm considering a 12 volt slow cooker, a 12 volt coffee maker and a twelve volt kettle. I'm wondering how well they may work. Any opinions out there before I lay down my cold hard cash? @};-
John Blue
Low voltage = high amps. Do you have the DC power to run this stuff? Save your cash!
RLM
pianotuna> I could not determine from your post or RV profile what type electrial service that your RV uses. If it is at least capable of 30 amp service, found at most campgrounds other than national parks, I wonder why you would need to purchase 12V appliances. If you are camping at places that have limited voltage, such as national parks with 20 amps only, then I would ask how many 12V plugs do you have? I don't think any RV has enough of those to operate simultaneously the number of appliances that you mentioned.

If you are dry camping without electical power, then power management is certainly a key issue. A generator would then be essential. There's not enough information in your posted question to properly answer it.
pianotuna
Hi RLM,

I often travel alone in my 25 foot 1987 Citation 30 Amp service with two solar panels and two 12 volt deep cycle batteries (420 amp hours). I do have a generator (2800 watts continuous Kipor), and a medium size inverter (700 watts). I do tend to boondock when ever I can, but prefer to not use the generator if at all possible. I'm lucky in that even a 15 amp service will run my roof AC.

What I am interested in doing is "going down the road" while my lunch or supper is "slow cooking" at the back of the RV (in the sink so if I have to stop it will not hurl itself all over the floor). I'm less than comfortable using the stove top for this purpose--and unfortunately my oven gas valve is shot. The shop wants an "arm and a leg" to replace it (over $400).

I saw a 12 volt slow cooker, a 12 volt frying pan, and a 12 volt kettle. They are intended for use with a cigarette lighter outlet. What I hope to find out is whether they are essentially "toys" or whether they will "cut the mustard". I would be using "one at a time" so the three outlets I have for 12 volt would not be a problem. I doubt that I'd buy the kettle, but the other two look intriguing to me, in particular the slow cooker, as I don't have a small one to use in the RV.

QUOTE(RLM @ Sep 6 2007, 10:38 PM) *

pianotuna> I could not determine from your post or RV profile what type electrial service that your RV uses. If it is at least capable of 30 amp service, found at most campgrounds other than national parks, I wonder why you would need to purchase 12V appliances. If you are camping at places that have limited voltage, such as national parks with 20 amps only, then I would ask how many 12V plugs do you have? I don't think any RV has enough of those to operate simultaneously the number of appliances that you mentioned.

If you are dry camping without electical power, then power management is certainly a key issue. A generator would then be essential. There's not enough information in your posted question to properly answer it.
gwbischoff
I'm certainly no electrician, but in my experience, anything that pulls a lot of power from a 12V outlet heats up the plug, especially if plugged in for any length of time. My concern would be for any appliance that uses some sort of heating element, like a crock-pot that it would overheat the plug. I have noticed that many 12V products do have a fused connection,tho.
RLM
pianotuna> Well, I'm going to stick with what I have experience with and that's nothing on 12V appliance capabilities other than the fans in my rig. I'm lazy, I like electricity, and I'll admit it. smile.gif Altho, if you do decide to part with the money for one, I'd be interested to know if they actually do the job well. You have an interesting concept for using them that might be worth trying.

However, I do have a background in electronics. Notwithstanding the heat issue mentioned by GW, the DC plugs in your rig are generally on separate fuses. Most are 5-10 amps. The cigarette lighter is usually 15 -20 and will handle a high current draw 12v appliance. The ones for things like a tv, fan, or the like may not. If you use one of the after market multi-plug adapters to plug more than one appliance into a single DC socket, you certainly increase the odds of blowing a fuse. So either way, please be aware of the amp ratings of the fuses. The amp rating of the appliance will be listed either on the label or in the manual that comes with it. 12v electronic items that are UL approved also come with a fuse built into the DC plug. They usually have an amp rating less than what your rig's socket fuses will be. That's a convenient safeguard that blows the appliance plug fuse before you blow the rig's socket fuse. It's easier to change that than it is to stand on your head, holding a flashlight up under the dashboard, trying to change a blown fuse. That is IF you can find it under the dash smile.gif Another thing to consider is the length of the cord that you need to run to plug an appliance into a distant socket. If you string out a bunch of wiring, you will increase the resistance which in turn increases the current draw and can overload the circuit. Result = blow fuse.

Since you have an inverter, have you tried using it to power a regular slow cooker while moving? My rig also has an inverter and we use it way more than we use the generator. I use it to power the fridge instead of using propane, run the laptop, and cook a quick microwave meal at a rest stop. The batteries that it draws power from are being recharged when the engine is running so battery drain is not an issue.

If you do use the inverter for dry camping needs, I would respectfully suggest that you buy a plug in volt meter to monitor it's output. They are about $15 and plug into a regular AC socket anywhere in the rig. You can monitor the voltage that is being used. If the needle drops out of the green arc, then you are overloading your inverter by using too many appliances at once. It's also good to monitor voltage when you are plugged into shore power. Low voltage is very bad for electrical appliances.

I have an image of your meal being "hurled" all over the floor. Probably not funny tho, huh?
gwbischoff
QUOTE(RLM @ Sep 10 2007, 02:37 PM) *


I have an image of your meal being "hurled" all over the floor. Probably not funny tho, huh?


"GW". I like that...

Does anybody remember the episode of the TV show "Wings" where Lowell is trying to sell everybody a "Car-B-Que" which cooks your meal on the engine manifold?

If anybody develops this for an RV, I want residuals. tongue.gif
pianotuna
HI RLM,

Yes I have gone one better than a simple volt meter--I have a power meter (called Kill a watt) that reads in watts what my draw is--and can check volts and amps too.

My Inverter does have over load protection built in and I use it mainly with resistants type loads--not motors. (Although I do have two fans that I sometimes run (one at a time). My inverter can reliably do 700 watts--and maybe a *bit* more with a surge...but I've not found a slow cooker that is of sufficiently low wattage. One solution would be a larger inverter--but I tend to be conservative as far as *price* goes.

I'm not too concerned about "blowing a fuse" with 12 volt devices. I do understand the limitations of the number of watts. But *sometimes* things work well when you don't expect them to do so.

Am off on a trip to Texas--and having a good time so far
HappiestCamper
I have found an easy solution for meals like this. I cook these at home, vacuum pack it, then freeze it. I leave them in the freezer (or fridge if I don't have enough room - I have just a one door fridge), then the night I'm having the meal, I boil a large pot of water, throw the bag in, turn the heat off, and leave it covered for about an hour (great the first night when you're setting up). The meal tastes great, though you miss out on the hours of smelling the meal cook right before you eat - but since you said it would be cooking while you're driving, you wouldn't have the wonderful aroma anyway. The big advantage is not having to clean as much at the campground.
BJMA
QUOTE(pianotuna @ Sep 10 2007, 11:20 PM) *

HI RLM,

Yes I have gone one better than a simple volt meter--I have a power meter (called Kill a watt) that reads in watts what my draw is--and can check volts and amps too.

My Inverter does have over load protection built in and I use it mainly with resistants type loads--not motors. (Although I do have two fans that I sometimes run (one at a time). My inverter can reliably do 700 watts--and maybe a *bit* more with a surge...but I've not found a slow cooker that is of sufficiently low wattage. One solution would be a larger inverter--but I tend to be conservative as far as *price* goes.

I'm not too concerned about "blowing a fuse" with 12 volt devices. I do understand the limitations of the number of watts. But *sometimes* things work well when you don't expect them to do so.

Am off on a trip to Texas--and having a good time so far


I would not consider 12V appliances when 110V appliances are available.

My background is electronics, mobile electronics, communications systems, building up broadcast remotes.

The plug in device, Kill A Watt, is not accurate unless the source is a pure sine wave. To accurately measure power using a power inverter and DC, you need something a bit better, such as the Fluke LH1050. It costs a tad bit more then $19.95, closer to $700.00.

Your concern is a simple matter of POWER. Using Ohm's Law, P=IxE, a 110V device will draw 3A, but a the same 12V version will draw 30A. This is of concern because now you have to deal with wire size, wire length, battery size, battery condition. At 30A, a handtight battery connector will overheat. Power is power, less efficiency.

The 12V device also cost more than a 110V "household" device.

I would suggest that you apply what you want to spend for a dedicated 12V device on a quality power inverter, and use the savings to buy 110V devices.
RLM
BJMA> I am sold on inverter power. So much so that I had one put into the wiring system of the house I recently built. With that, a bank of six batteries, and small windmill charger, my electric bill has never been over $100 even when I run AC in the summer, which it does not power.

pianotuna> I'm based in central TX. Bring plenty of air conditioning for your trip. It's still in the 90s.

Don't know where you're headed, but San Antonio is always a good place to visit. If you haven't already picked them out, I can give you some suggestions on nice campgrounds in the state.

Pick up a current Texas Travel Guide at one of the entry rest stops. Mucho good info in it.

And don't tell any native Texan that you don't like Chicken Fried Steak. That's a hangin offense here. wink.gif
pianotuna
HI RLM,

I'm going to a place called Possum Lake where there is a motorcyle rally this coming weekend. It's near Graham TX.

I'm just the driver and bottle washer for this trip. I'll be visiting Walmart for an oil change and tire rotation. Probably on Friday.
DXSMac
Interesting topic. I don't think 12 volt appliances would be a good deal, especially appliances that generate large amounts of heat, such as cookers. However, my first RV had a 12 volt TV. I liked that feature, because when I was dry camping, I could watch TV. The RV I have now is electric. I would have to turn on the generator to watch TV. I just have this "thing" that the generator is only to be used for Life Support (heat or air conditioner if necessary) and not "toys." So, in my current RV, if I don't have power, I don't watch TV.

JJ
ddbradley952
QUOTE(pianotuna @ Aug 31 2007, 05:59 PM) *

Hi,

I'm considering a 12 volt slow cooker, a 12 volt coffee maker and a twelve volt kettle. I'm wondering how well they may work. Any opinions out there before I lay down my cold hard cash? @};-

No. it will kill all your batteries in about 15 minnutes, long before anything is warm. buy a 1,000 watt smart inverter and add extra dc batteries (preferrably 4 golf cart batteries) and change your alternator to a heavy duty 200 amp alternator for fast charging.

Except for cigarette lighters, Never use DC power for heating applications.not talking about the furnace btw. I got 4 new large group31 deep cycle batteries off Craigslist.org for $40.00 total.
ddbradley952
QUOTE(DXSMac @ Sep 23 2007, 03:47 PM) *

Interesting topic. I don't think 12 volt appliances would be a good deal, especially appliances that generate large amounts of heat, such as cookers. However, my first RV had a 12 volt TV. I liked that feature, because when I was dry camping, I could watch TV. The RV I have now is electric. I would have to turn on the generator to watch TV. I just have this "thing" that the generator is only to be used for Life Support (heat or air conditioner if necessary) and not "toys." So, in my current RV, if I don't have power, I don't watch TV.

JJ


Get a 700 wat smart inverter, one that turns on with a switch not a buble button and only runs its internal cooling fan when consuming electricity and add as many deep cycle batteries as your wallet can stand. I got 4 large new deep cycle batteries off craigslist for $40.00. cool.gif
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