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Might be worth mentioning what car you have and the type +(power output) of the converter you're planning to run. Nobody can guess the answer without that basic information.
Ooops I'm mechanically retarded> I've got a 2008 Ford Edge the current inverter is 200 max output of 400 either amps or watts heck if I know the diff.
With government shutting down and pay being most likely suspended looks like I may be in SUV for a bit. I'd like to run one of those ceramic heaters, but if I constantly having to keep car running then whats the sense really. I've seen enough on shows like Myth Busters that your A/c and air compressor doesn't really affect your gas mileage to much so what's the point of having fan portable heater etc.
Every power inverter has a power rating in watts. The typical inverter intended for use in power outlet (lighter socket) is 200-400 watts. That's enough to power electronics and lighting, not power tools or heating devices. A hair dryer requires 1000-1500 watts. Many of those small "ceramic" heaters need 1500W. That means you would need a big inverter that connects directly to the battery.
Oh - and the battery wouldn't last long powering a heater like that.
Outstanding the straight to it answer I was looking for, so what's the sense really cause from what I've seen and read AC and Heater doesn't effect your gas that much so why not just periodically crank car up get warm then shut it off.
400W is not really a whole lot. That's only about 3A of 120V power. I know of blenders that draw more power than that. I don't think you are really going to be able to do what you want to do here.
Hate to say it, but idling the engine for heat may be the best method short of spending money on additional 12V batteries, a larger inverter and such. It might be cheaper just to buy gas
I've seen and read AC and Heater doesn't effect your gas that much so why not just periodically crank car up get warm then shut it off.
Heat doesnt use any additonal fuel when in use (as long as the A/C compressor is off). It just uses the engine coolant to warm up a small radiator in the engine bay. Since you need to cool the engine, this is just taking some of the heat and diverting it into the passenger bay. Having the heat on, vs Off will make no difference in fuel economy.
A/C is a different story. Most studies tend to look at A/C use vs open windows on the highway. many have shown that over a certain MPH, it's cheaper to use the A/C vs rolling the windows down. At lower speeds, the windows down may offer savings over using the A/C. But powering up the A/C will cause a small reduction in fuel economy, and if you are going to idle in place, it definitely will use up more fuel than not running it at all. There is a additional load on the engine when the compressor turns on.
One thing i will suggest is to pay attention when using the heat. A lot of cars these days have automatic climate controls that default to running the A/C compressor to control humidity. Even if you crank the heat to 90, the A/C may be on. Sometimes there is a button with a LED indicator to show if it's on or not. You may need to make sure the A/C is off. Whenever using the defroster, the A/C is defaulted to on unless you manually turn it off. It can be 20 degrees outside, and usually hitting defrost will still kick it on.
Seeing as winter is coming, unless you need to defrost the windows, no reason turn the A/C compressor on with the heat, so def make sure you understand how your HVAC system works and pay attention to keeping the A/C off.
A typical ceramic heater will draw up to 1500 watts. That means you would need at least a 1500 watt inverter. They are big, not cheap, and need to connect directly to the battery.
1500 watts using a 12V power source would draw 125 amps, which is a huge amount. Very powerful car stereos do not draw that much. Your car battery would be drained quickly.
It is just not a good way to generate heat. Get a long extension cord for the heater.
1500 watts using a 12V power source would draw 125 amps, which is a huge amount. Very powerful car stereos do not draw that much. Your car battery would be drained quickly.
It will actually be more than that, perhaps considerably more if one is using one of the cheap inverters out of China.
1500/12=125 assumings 100% efficiency in conversion, which the current laws of physics would not allow. You're going to lose some power in the cabling from the battery to the inverter, and some more in the inverter itself in the conversion from DC to AC.
The best inverters on the market meant for solar use are seeing efficiencys maxing out around 98% (and these are the monster inverters meant for powering entire buildings, not the smaller stuff installed in our cars). The better smaller inverters for mobile use might be around 90%, and I've seen less than 50% on some of the ultra cheap Chinese inverters, such as you might find in some place like Harbor Freight. Not an overly huge deal if it's being used with the engine running, but can become a very big deal very fast if you're strictly on battery power.
At 90% efficiency, you'll be pulling ~140amps on a resistive load at 12VDC input, ~165amps at 75% efficiency, and 250amps at 50% efficiency. Using my Statpower 800 watt unit as a reference again, peaking the inverter should draw ~60 amps with the engine running assuming perfect efficiency. The reality was that it drew ~80 amps at a 13.5VDC input, which equates to roughly 75% effieciency. This was on 2 gauge cabling, which is bigger than the 4 gauge recommended by the manufactuer, to minimize input power losses.
They are also typically rated for purely resistive loads as opposed to inductive loads (such as an electrical motor), and very near full power. Drop the load, and often the efficiency plummets. Occasionally I'll hear from someone confused as to why they bought a monster inverter, attach a small load to it, then see their battery drop faster than with a smaller inverter.
This means that say you have a 1500 watt inverter running a 400 watt load. You might see something like a 70-75% efficiency. But plug that same 400 watt load into a 500 watt inverter, and you'll see the efficiency jump to around 90%.
This also assumes the use of purely resistive loads, such as the electric heater or lighting. Add some motors to the mix, such as the fan behind the heater, or other appliances, now you get into start up surge current of the motors, and considerably higher power being pulled than what the motor is rated at on AC, due to the modified wave form of the inverters if you don't get a true sine wave inverter.
It will actually be more than that, perhaps considerably more if one is using one of the cheap inverters out of China.
1500/12=125 assumings 100% efficiency in conversion, which the current laws of physics would not allow. You're going to lose some power in the cabling from the battery to the inverter, and some more in the inverter itself in the conversion from DC to AC.
The best inverters on the market meant for solar use are seeing efficiencys maxing out around 98% (and these are the monster inverters meant for powering entire buildings, not the smaller stuff installed in our cars). The better smaller inverters for mobile use might be around 90%, and I've seen less than 50% on some of the ultra cheap Chinese inverters, such as you might find in some place like Harbor Freight. Not an overly huge deal if it's being used with the engine running, but can become a very big deal very fast if you're strictly on battery power.
At 90% efficiency, you'll be pulling ~140amps on a resistive load at 12VDC input, ~165amps at 75% efficiency, and 250amps at 50% efficiency. Using my Statpower 800 watt unit as a reference again, peaking the inverter should draw ~60 amps with the engine running assuming perfect efficiency. The reality was that it drew ~80 amps at a 13.5VDC input, which equates to roughly 75% effieciency. This was on 2 gauge cabling, which is bigger than the 4 gauge recommended by the manufactuer, to minimize input power losses.
They are also typically rated for purely resistive loads as opposed to inductive loads (such as an electrical motor), and very near full power. Drop the load, and often the efficiency plummets. Occasionally I'll hear from someone confused as to why they bought a monster inverter, attach a small load to it, then see their battery drop faster than with a smaller inverter.
This means that say you have a 1500 watt inverter running a 400 watt load. You might see something like a 70-75% efficiency. But plug that same 400 watt load into a 500 watt inverter, and you'll see the efficiency jump to around 90%.
This also assumes the use of purely resistive loads, such as the electric heater or lighting. Add some motors to the mix, such as the fan behind the heater, or other appliances, now you get into start up surge current of the motors, and considerably higher power being pulled than what the motor is rated at on AC, due to the modified wave form of the inverters if you don't get a true sine wave inverter.
This is puzzling to me. My 2800 watt (peak) inverter is on a 30 amp fuse. I do not know what the real (continuous) output is, but it is at least 1400 watts and I think it is higher. If it was drawing over 100 amps the fuse would trigger, but it does not. The inverter mostly runs computer equipment, a printer, communications devices, cameras, recorders and security encryption equipment. Only small fans and other small motors, so maybe it just does not draw peak power.
Are you intending for this to be funny? Honestly, I'm smiling as I look at what appears to be some PVC painted silver. That "atomic heater" would work, but only because it is actually THIS:
Because either you're not pulling 1400 watts of power out of it, or your inverter is grossly over rated. Probably a combination of both.
Watts are determined by a simple formula - P=V*I. P=power (or watts), V=voltage, I=current in amps.
P=12V*30amps, gives you 360 watts. If the car is running, and producing 13.5VDC, you'll 405 watts. (see Electric Power )
Given the equipment you listed, you're well within the capacity of a 400 watt inverter. For years I ran a full desktop tower style computer off a 400 watt inverter plugged into the cigarette lighter. Assuming I turned the computer on first, I was even able to run a monitor off it as well, but if the car's voltage dropped even a tiny bit, the inverted overloaded.
Even in the case of something like a computer (desktop or laptop), the listed power requirements on the power supply are peak loads. Using the common laptop adapter that may something like like 19VDC @ 4 amps (which would be 76 watts output...likely using something around 90 watts input), you'll only see that power draw at the peak load with everything running full on - dead battery charging, hard drive spinning at max speed, fan spinning at max speed, optical drive spinning at max speed, screen brightness at full bright, CPU running at 100%, GPU running at 100%, etc. During normal usage, it's proably pulling less than 20 watts output.
So adding up the power requirements of everything you're running based off the labels may result in considerably higher numbers than the amount of power you're actually using.
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